General Ham Radio – Page 2 – NT1K

New Gear: Heil PR-781 Microphone

I almost have my station setup to where I’m satisfied. Everything is controlled within arms reach to where I can operate the computer and radios at the same time and with ease. During 2011 NEQP, It got un-comfortable operating a couple of hours in while lurched over my Yaseu MD-100 desktop microphone. I think it led to less operation and just a lack of motivation. For the 2012 NEQP I wanted to be more comfortable. I purchased a Heil Pro Headset ($140 + Cable) and modified a Radio Shack tape recorder foot switch to work with my FT-950. This years contest turned out to be a lot different in 2012. I doubled and almost tripled last years score. It was due to being comfortable and dedicated to staying on the air.
I love the Heil Pro Set but I don’t like the way it sounds. The one I purchased uses the HC-4 Element. From what I’ve read on the Heil website that the HC-4 was designed for mainly contesting or DX. It cuts off the low frequency and focuses on the HIGH parts of your voice. Meaning the rumbling lows in your voice (if you have any) will be mostly removed.

Here is a youtube video of how I sound on the Heil Pro Set using a SDR Receiver

You will notice there is little to no bass on my audio. It has a narrow bandwidth which is great for contesting. It Could help you break a pileup because your “Cutting” in with the sharp audio. In my personal opinion (I am not a audio expert by any means), it’s a great microphone but it’s not for everyday use or ragchewing. Maybe the Pro Set Elite has a much wider response and would be worth the extra $$$ for it to be used as a everyday microphone.
Now I am back to being hunched over the Yaesu MD-100A8X ($150). I am getting more uncomfortable the more I’ve been talking on the air. It ended up where I was propping up my head with me arm while talking. The constant pressure from my arm caused some issues with my Jaw. I ended up grabbing the mic stand by the stem and using it that way which was awkward. YAESU claims the microphone could be separated from its base but I am not sure what they mean by that. Could the microphone be used without the base? It does have a TX button on it and it has a 8-pin port on the back of the microphone itself. The cable that comes out of the base to connect the microphone is very short (6 or so inches?) and would not really allow you to “Seperate” the micrphone unless you somehow make a cable that connects from the back of the actual microphone to the transceiver. I wasn’t sure of the pinout of the actual microphone and I wasn’t going to open it up to find out.

Here is a video of what I sound like using the MD-100

After being uncomfortable and finding out that a lot of my Jaw pain was insult of applying pressure to it often (I also do it at work), I decided enough is enough and wanted a new microphone. Don’t get me wrong, I LOVE the MD-100 and after tuning the FT-950 Parametric EQ to my liking, I’d often get reports on how “GUD” my audio was. I actually took pride on getting positive comments and people asking what microphone I was using.

So now that I need a new microphone, I figured I can upgrade at the same time. The only true requirement is to be able to mount the microphone on a boom. I was also thinking to use the microphone if I ever get into Podcasting. This led to a major road block. There are hundreds of different microphones out there. There are some that should not be used in Amateur Radio but there are many that could. I wasn’t sure what to get so whenever I heard a really nice signal on the air, I would look up the call to see if I can get what kind of microphone was being used. It helped a little bit but there is still a wide range of microphones that are out there. From the very expensive condenser microphones down to microphones that are used with computers. I also had a budget of $150-$200 for a microphone and really didn’t want to go over it.

I ended up going with Heil PR-781.

The reason I wanted to get the 781 is because it’s designed with Ham Radio in mind. I know I can get a microphone that could do almost all the same things for cheaper but I’ve purchased Heil Sound products before and had nothing but good things come from them. And if something does happen, their support/customer service is outstanding. Try getting support for your drop shipped microphone and you will know why.

I wanted to go all out and get EVERYTHING for the microphone. That includes the microphone ($175), shockmount ($100), cable ($40), and boom arm ($120) which would end up costing $415. That costs more than what I paid for my Amplifier. There is no way that I am going to spend that much money when I am already spending a lot on something that I already have. I ended up buying just the microphone and cable which with the sales HRO is having at the time, I ended up paying less than $200. The reason I paid for the cable instead of making my own is that I don’t have XLR connectors, 8-Pin connectors or any cable to wire one up with. I also read that the FT-950 needed a balanced input and there a issue with the FT-950 can get RF into the cable so I bit the bullet and got the cable.

The only issue I have is to where I am going to mount the microphone since I didn’t purchase a mount/boom. I went up to the attic and sure enough I found some desk lamps that had booms. I thought the lamp head was similar in weight to the microphone so I thought I can get rid of the Lamp, keep the boom and fit it to the microphone holder. It ended up to almost a perfect match. I wouldn’t be able to swivel the microphone left and right but I didn’t mind. Once I mounted the microphone, I found out that the mic is a lot heaver than the lamp and was pulling down the springs and not staying where I placed it. The solution that problem was rubber bands. I placed a bunch of rubber bands along the spring and balanced the microphone perfectly. Also got rid of any spring noises.

Another great thing about the FT-950 is that it has a decent parametric EQ built right in. I can adjust how I sound from the radio instead of buying a mixer board. I used the settings suggested by Heil Sound but tweaked them so my lows would stick out and give my voice a bassy feel to it.

Here are my FT-950 Settings

Menu #62 – TX BPF (Maxium Signal Width) = 1-29 (100-2900hz wide) or 2-28

Menu #91 – Frequency = 200hz
Menu #92 – Notch or Boost = -4 (db) (Heil Suggests -15 which eliminates a lot of bass, Good for DX)
Menu #93 – Bandwidth = 6 (Heild Suggests 5)

Menu #94 – Frequency = 700hz (Heil’s site says 400hz which the radio can’t do. 700hz is the minimum)
Menu #95 – Notch or Boost = -0 (db)
Menu #96 – Bandwidth = 5

Menu #97 – Frequency = 2400hz
Menu #98 – Notch or Boost = +8 (db)
Menu #99 – Bandwidth = 5

Menu items 91, 92 and 93 are for your low range. This will give or take away all the lows or bass in the signal. Items 94, 95 and 96 are for your mids and 97, 98, 99 are for your highs and will make your voice more coherent (unless you have marbles in your mouth) . Well… That’s what I think it does for me.

These settings are the ones that I use for Ragchewing (seem to be doing more and more). It wouldn’t be much for contesting or chasing DX. At this point I will change the Settings to narrow up the signal and get rid of some or most of the bassy lows that are in my audio.

Here is a Youtube video on how I sound

After watching the video a couple of times, I think it’s great for 75M Ragchewing but not so good chasing DX. I will have to find a happy medium and remember the settings.

Just for reference, I also made a video of what the MH-31 hand microphone that comes with FT-950 sounds like.

It’s been a week since I’ve been using the microphone and I really like my purchase. Already got some good audio reports. Now I want to get the podcasting side of it going.

Thanks for reading

Field Day Fever

Even though Field Day (FD) is weeks away, the planning of it gets me excited knowing that it’s near. Field day is the basically the main reason why I got my license. During my CB days, someone brought me to a field day hosted by the MTARA (Mount Tom Amateur Radio Assn.) on top of Mount Tom around 1995. I recall being on 14mhz using a Kenwood TS-440 and was making contacts all around the country. Compared to CB I was amazed about the contacts I was making considering I would never hear the stations, let alone make contact with them on CB. Field day was the kick in the ass to get my license and pretty much put CB behind me.

For those who don’t know what Field Day is, I would check out this website that would explain it in more detail then I could. It’s a emergency preparedness exercise where operators try to contact with as many other operators as possible. Even though you don’t have to, it’s encouraged that you bring your gear and communicate from a field, hence “Field” Day. A lot of local Amatuer Radio Clubs put on events related to FD to have fun and also promote Amateur Radio to the general public at the same time.

Last year I participated in Field Day with the Hampden County Amateur Radio Association running the digital station.

NT1K FD 2011 — NT1K Doing Digi (Photo By: Frandy Johnson, N1FJ)

This year I will be running SSB on 40M (7mhz) with the HCRA again at Dufresne Park in Granby MA. If you are in the area. You should stop by and check it out. Go Here for more information

Obtained DXCC Mixed Status

After a year of chasing stations, waiting hours in pile-ups, chasing LoTW DX ops and checking LoTW whenever I uploaded my logs. I finally got enough entities to apply for my DXCC award.

Earlier this week I have DX Labs Spot collector running and with 20m acting the way it has been for the past week (very good), I saw a couple stations being spotted that I’ve never worked on before. I got to work ZL2WL (Wayne, New Zealand) and MD0CCE (Bob, Isle Of Man). MD0CCE uses LoTW and confirmed to be my 100th entity. Then last night I made contact with MW0ZZK (Steve, Wales) that confirmed my 101 entity.

Now I need to apply and get the paper. Then I’ll start working on 5-Band DXCC and finishing up my WAS

Thanks to all who use LoTW!

Edit 6/7/2012: I submitted my application using only LoTW credit and using the LoTW website on 6/1/12 and I got the actual certificate in today.

The NT1K Webcam Is Now Active!

You can now visit the NT1K Webcam here.

I’ve decided to add a webcam to the NT1K shack and it will be broadcasting whenever I’m on the air for an extended period of time. The audio will be fed from the radio so you can hear whats going on the Air. It’s the best choice since I mainly use headphones while on the radio. The camera will either be focused on the shack itself or the front panel of my radio so you can see what freq I am on and possibly see how well you come across my station.

Live stream by Ustream

Press the play button. If it says “Recorded Live” that means I’m not live and you’re seeing/hearing a past QSO.
If I happen to remember, hopefully you will see QSO’s with DX stations

Contesting… Huh?

As this blog is geared to newer hams, you’ll sometimes hear the word “contesting” or “radio sport”. Sometimes I think it’s funny seeing or hearing Ham Radio and sport in the same sentence. It reminds me of a scene in the movie “King Pin” where the character played by Randy Quaid says, “It’s intimidating to be in the presence of so many great athletes.” Then the shot pans to a bunch of fat guys smoking, eating and drinking. Sort of an oxy-moron if you ask me.

So what is this “contesting” and what’s it about?

As simply as I can put it, Contesting is where a operator or operators try to establish contact with as many other operators as possible within a certain period of time. What makes each contest unique are the rules and regulations that govern each contest. Most contests have the operators send a piece of information to the other operator and vise versa. This “Exchange” is used by sponsor of the contest to ensure that an actual contact actually happened. Once the contest is over, all the operators that took part in it will send in their logs to the sponsor before a deadline. The sponsor will then enter all the logs into a database and it will cross check all the logs and award points. The points are awarded depending on the rules of the contest. It can be as simple as one point per contact or 2 or 3 points. There are also Multipliers (mults) which are defined by the rules of the contest, making contact with a mult will multiply your entire score by that amount.

The one with the most points wins is a general way to put it. Depending on the contest, there could be multiple winners for all the different categories they have. Some of those categories could be QRP, Low Power (>100W), High Power(<250W), Emergency Power, Single Operator, Multiple Transceivers with Multiple Operators, Single Transmitter with Mulitple Operators, Rover/Portable (Driving around) are just some of the categories that could be used in a contest. Just read the rules of the particular contest and you will know where to fit in or what to aim for.

Is contesting for me?

That all depends on you. Some operators love it. They eat, drink and don’t sleep contesting. The only time you will see them on the air is during a contest. There are even clubs dedicated for contesting. I belong to the “Yankee Clipper Contest Club” (YCCC) and they take contesting very seriously. If you are into contesting I would suggest to join one. As I did with the YCCC, you can learn a lot about contesting . It’s not necessary but If you get bitten by the contesting bug, the information and help from fellow members is worth the membership fee.

Some of the operators who do a lot of contesting, setup their stations with only contesting in mind. Some ops go as far as buying property and building their station around contesting.
I had a chance to visit one of these contest stations and I was quite impressed with the setup. The station I got to visit is built and owned by Dave Robbins (K1TTT). I got to operate at his station with the BSA Venture Crew 510 (NE1C) for both the North American QSO Party (NAQP) and WPX SSB.

Here is what is station looks like

Pictured: John (Kx1x) and Nick (K1MAZ)

You’ll notice that there are multiple transmitters scattered throughout his station. Each area is basically dedicated for a single band. If the contest allows, there can be 6 to 9 transmitters being used at the exact same time. The software (N1MM) that is being used is networked throughout his entire shack. This will show real time progress of the contest and predict a very accurate score. It could also lead to a little contest between operators to see how many QSOs each operator can make.

Here are some of the Antennas that make this station possible

I didn’t have time to take photos of all of his antennas but it’s quite impressive. If you want more information about K1TTT, you can visit his website.

With this Station/Setup, It’s NOT hard to have a high score. Since this is what is considered to be a “BIG GUN” station, it’s easy to take command of a frequency and “Run” for a good portion of the contest. Let the contacts come to you. The only thing I did not like about using his station is when I returned home to use my equipment only to hear a fraction of what I just heard at the contest station. But if you ever have a chance to use a contest station, go for it! You can learn a lot about contesting just by watching someone who has done it for a while.

Now don’t let me scare you out of contesting by saying you need to have this “BIG GUN” station. The truth is a lot of the stations that participate in contests have what is considered to be a “Normal” setup. If you’re still on the fence about contesting, my advice would be to find someone or a group within a reasonable distance and shadow them for a contest. If you join a contesting club (if it’s possible), there are contesters who are looking for more operators as they work in “Shifts” depending on the contest. Another thing you can do is wait for Field Day. Even though the ARRL calls Field Day a emergency preparedness exercise, it’s could be considered a contest or even both. You get points for making contacts and points for doing certain things and they publish the results every year. Visit a Field Day site and you will get a general idea on how it works. If you don’t want to transport to another station, as long as you have the equipment, there is nothing to stop you from contesting from your home (other than your license limitations).

The Dark Side of contesting

Not all Hams enjoy contesting. Actually some Hams just flat out HATE contesting and anything to do with it. Some of them beleave that contesting actually ruins amateur radio because it’s turning a leisurely hobby into a “Sport” and it’s congesting the airwaves with nothing but false exchanges transmitted by operators who are over-driving their signal and using more power than the legal limit to force other ops off the frequency and/or band. You’re not learning about the person on the other side, you’re just establishing contact and moving on.
That is basically what you will hear from the “Anti-Contesters” and I think it’s a half truth. There are operators that show no respect and do all of those things. But it also happens when there is not a contest going on. When a major contest is going on, depending on the contest, there is a lot of activity going on. There is so much activity that it’s very possible that the entire band is being consumed by contesters. There is refuge from all this chaos however. Most, If not all contests do not allow contesting on the WARC bands (60m, 30m, 17m, 12m) so if you don’t like contesting, you can use these bands. The downside to the WARC bands is that you have limited space and there are not many antennas designed for the WARC bands which keeps some operators off.
Most contests take place during the weekend. A good amount of the contests are mode specific. So if it’s a RTTY contest, most of the activity will be around the RTTY calling frequencies and the SSB portion will be not effected. Same with CW or PSK or SSB only. However there are contests that any and/or every mode can be used.

If you’re an avid “Rag Chewer” contesting might not be up your alley. Don’t knock it down until you at least put a serious effort into contesting. If you’re going into contesting with a negative attitude, you’ll have negative results. If it ends up that you don’t like contesting for whatever reason, please don’t turn into a “Anti-Contester”. Just because you like telling your story to every ham that you come across doesn’t mean that every single amateur radio operator should be doing the same thing. Some hams are in it for CW, some are in it for Ragchewing, some are in it for chasing DX, some are in it for EmComm (Emergency Communications), some are in it for contesting and yada yada yada ya. Ham Radio is a big melting pot of all different types of people and the different ways they communicate. It shouldn’t be subject to a single use.

I want to try contesting, what do I need?

As I stated earlier, you don’t need a “Big Gun” station to participate and have fun in a contest. All You need is time, will and determination more than anything else. Oh and at least some equipment. If you already have a transceiver, antenna and a way to log the contacts then you are all set for contesting. If you’re comfortable with just that then hopefully you’ll have a fun time contesting.
There are things out there that will make your contesting experience much more enjoyable and will give you a better chance of a higher score. In my personal opinion, the biggest contribution to contesting is the personal computer. With that and CAT control and possibly an internet connection, it will make you much faster in the contest. With a computer you can use logging software in combination with rig control to log the frequency, time, call-sign and exchange. Depending on the software, it will estimate your score. That depends on if the other stations you’ve contacted submitted their logs.

Some other things that can help you in a contest are a Headset (For SSB) with either a foot switch or the VOX (Voice Operated Transmission) enabled on your radio (if you have one). That will free up your hands for logging and other things. It will also block most of the noise happening in your environment. A memory keyer (CW/SSB/Computer) would be beneficial for both CW and voice contesting. What the memory keyer does is store messages that you will be sending over and over again. For example if you say “CQ Contest CQ Contest This Is November Tango One Kilo Contest” hundreds or thousands of times throughout a contest, it can get tiring and you’ll sound horrible towards the end of the contest. The memory keyer will store the message and play it over the air whenever you push a button. So you can store things like CQ, Your exchange (if there is no serial number involved or anything that is different per contact), “Thank you, 73”, “QRZ This is NT1K” and other things that you might say repeatedly. Same with Morse code. A lot of this can be done with the computer. However, you might have to add an additonal piece of equipment called a “Sound Card Interface” like the Rigblaster or SignaLink for voice and/or some kind of CW interface like WinKey. You can also just buy the hardware (linked earlier). There are many options out there, some people use a couple of Audio cables and the VOX on their radio as an interface.

In short, a ideal contest setup would consist of your transceiver(s), antenna(s), computer w/ appropriate software, headset and/or memory keyer (either software or hardware).

I have what I think is needed for contesting. What do I do?

First off, see what contest(s) are out there that you are interested in and see when they happen. This website catalogs the upcoming contests and gives you the basics about each one. Most contests have a website that is dedicated to the contest in question. I would visit that web site, read and understand all the rules for that contest. Nothing is more embarrassing then not reading the rules and participating in a contest where all the work that you did could be flushed down the toilet.

Next thing to do is to set your goals. You can aim to beat your last years score, the score of a rival operator or operate for X amount of time or X amount of contacts. You can aim really high and set your goal to WIN the contest.

If you are brand new to contesting, I would read the rules and listen in on a different contest before taking part in the one that you’re interested in. That way you have a feel for what’s about to happen. If you’re in a contest that is using a “Digital” mode (such as RTTY, PSK, CW, FeldHell, etc.. ) it would be wise to setup “macros” or scripts needed for calling CQ and making exchanges. Nothing is more irritating when you’re in a PSK or RTTY contest and the persons macro is a mile long causing the QSO to take way longer than it should.

About a week before the contest begins, start checking your equipment and software to make sure everything is in working order. That way you’re not running around like a chicken with it’s head cut off looking for hardware to replace your non-working hardware or trying to fix the software you’re using.

The day before the contest starts I would check your equipment again and configure your software (if you’re using it) to the contest that you will be participating in. If you’re using rig control, make sure that it works and everything communicates with each other. Then I would test your setup by getting on the air and making contacts. If you happen to have towers and beams or directional antennas, have them pointed in the direction you need them in.

Get a good nights sleep. You don’t want to be exhausted when getting into the contest. Depending on the contest, you might NOT be sleeping for the next 48 hours. So plan accordingly. Hours before the contest starts, I would do one final check of you’re equipment. Depending on how serious you want to be, I would also take this time to setup your area. Make it as comfortable as possible since you might be planted there for a long time. Things like having a stocked cooler and/or coffee maker within arms reach can really make things easier. Same thing with snacks and/or meals. If you’ve ever done gaming then you should already have an idea of what it’s going to be like. This may sound extreme but that’s how some people do it.

Contest Started. What do I do?

To answer that easily… GO GO GO!! What are you waiting for?!? Start!.. Every couple seconds of just sitting there wondering could cost you points. The ideal thing to do would to take command of a un-used frequency (good luck) and start calling “CQ contest…” (running) and start racking up those contacts. However depending on the contest, you might get pushed off by the “BIG GUNS”. It’s happened to me (even when I was using a “BIG GUN” station) a lot and I am sure it will happen to you. It’s hard to compete when the “Big Guns” are hogging up the band. Don’t let that make you lose hope. Use that to your advantage. Work all those “Big Gun” Stations and do what it called “Search & Pounce (S&P)”. Start from the beginning of the band and turn the dial towards the end of the band, working as many stations as possible. Depending on the contest or the rules or the category you’re running in, once you reached the end of the band, go the next higher band and do the same thing over and over. If you happen to find an empty frequency that can be used then stop S&P and go back to Calling CQ (Running) and repeat.

Another way people contest (if it’s allowed in the contest) is to utilize the Spotter/Skimmer/Packet networks that are out there. For those who don’t know what this is, it’s the exact same thing as a “DX Cluster”. What happens during the contest is after the operator makes a contact, the frequency and callaign will be “Spotted” on the network. For CW there are computers that use SDR (Software Defined Radio) that can look at almost 200Khz worth of bandwidth, decode the CW and post the spots on the cluster. They call this skimming. If you have the appropriate software and it’s setup correctly, you can have all this information displayed on your computer and all you would have to do is click on the callsign you want to make contact with and it will automatically put you on the frequency they are on and partially fill out the log book. The downside of this is that it could possibly put you into a different category. It’s may be fine for some contests (because you’re already in that category) but will make it difficult for you to even place in other contests because there is a possibility that you will be lumped in with the bigger stations.

What can I do to have the Highest Score Possible?

Well, that depends on you and your will, determination and the goals you set before the contest. If your goal was to operate for at least a couple hours and you did then your Goal has been achieved and your score will reflect it. However there are things that you can do to get the highest score possible. The fastest way to a high score is to work multipliers(mults). I brushed on this earlier but depending on how the contest is setup and governed, certain stations are considered multipliers. If you work that station and get confirmation, your score will multiply by that amount. So if you worked 54 (1X) multipliers, each contact (QSO) would be 54 points. If you’re working assisted and depending on the logging software, it will tell you that you’re working a multiplier and your predicted score will change.

Another thing to do is stay active. Some people are only active when the band is “Open” and go off to do other things when the band dies down. Spend some time before the contest looking at and learning HF Propagation charts (Link 1|2|3|4). Make a print out of what bands will be active at certain times and try to get on before the band “Opens” up. Hopefully that will give you a jump and possibly a running frequency. If the contest involves working stations in Europe, you most definitely want to be on the air when the band opens up to Europe due to the massive amount of stations and countries in that area. If the contest is a “work anyone anywhere” type then when the band dies down, concentrate your efforts to working contacts in your area/country. There might be a time were it seems dead. At this point find the most “Active” band and setup camp calling CQ. Contacts will come trickling in but it’s better than not making contacts at all. I also have either my laptop/tablet/smartphone going so I can be doing other things while calling CQ and stopping to make the contact.

Quick Notes On Contesting:

Set your goal – Is it to be on for X amount of hours? or to make X amount of points? or to beat last years score? or to WIN!
Check Check Check your equipment – Don’t want to spend the first 3 hours of the contesting fixing things.
Be comfortable – Setup the area to be as comfortable as possible. Possibly have food and drinks within arms reach.
Know band openings\closings – Use HF propagation prediction software/sites so you know when a band is opening/closing
Three tries – If you can’t get the station within three tries, move on or say “Sorry, I can’t work you, please try again later. QRZ” . If they are strong, the chances of them of being there on your next go-around will be high.
No Ragchewing – The point of a contest is to make as many QSOs as possible. Talking to another contester will end up costing you potential contacts and will annoy the other contester.
Start low and repeat – If you’re S&P, start at the beginning of the band and work your way to the end. At the end, move to the next band higher until you’re high as you can get and then start over at the lowest possible band and repeat. Like a cirrrrrrcle.
Follow the DX Code of Conduct – Even though this should be followed at all times. It’s more important during a contest. Not everyone follows this but after some time contesting, They stick out like a sore thumb and will be labeled a LID (poor operator)… Don’t be a LID.
Keep going – Make as many contacts as you can within the time period you’re allowed. Try to stay at your station

Contest is done… Now What?

After you recover, I would glance over the logs to see if anything sticks out that is wrong like invalid callsigns or bad exchanges and see if you can fix them or possibly remove them (I would try to fix them). Some contests will give kudos to those whom submitted error free logs.

After checking the log, export it in the format the sponsor asked for (mostly carbrillo format) and check the rules of the contest to see how or where you have to submit/upload/e-mail your logs to.

Even if you were in the contest for 10 minutes, If you made contacts, I would submit a log file. There is no FCC Law saying you have to submit a log, but depending on the contest, it might take points away from the other operators since it’s won’t be a true contact since there is no confirmation from you. So if you take part in a contest, please submit a log. Even if it doesn’t benefit you. It’s just good practice.

Was it worth all the time and trouble?

Once again, that all depends on YOU! Did you have a fun time? Did you reach your goals that you’ve set before the contest started? Was this your first time participating in this particular contest? Did you end up getting a certificate or winning a category? All of these questions will tell if you if it was worth it. A great thing about contesting is that you can use the contacts that you made during the contest to count towards awards like DXCC or WAS (that is if you were using YOUR callsign). And if this was your first contest, now you have a base to set your goals for.

NT1K Experiences in Contesting

At the time of writing this article, I’ve participated in a few contests. I am nowhere near being an “expert” at contesting and I don’t have what is considered to be a “BIG GUN” setup. I’m writing this hoping to drum up at least some interest in contesting from those who are just getting into the hobby. There are other articles by veteran contesters that are much better. If you have the chance to join a contesting club, go for it! If you didn’t learn anything from joining and participating in a contest club then I would question what type of club it really is. Some clubs even hold “Contesting Classes” where they will walk you through the details of contesting. You can also attach yourself to a group within the club (and hopefully near your QTH as well) and shadow them to see how it’s all done. Some of these contesters are begging for ops to come over and operate using their callsign (or club call) so they can take a break. Some are willing to teach you (isn’t really hard to say you’re 59 and the exchange) so they can have a semi warm body at the radio making contacts.

My Contesting setup is made up of the following

Transceiver: Yaesu FT-950 HF/6M – It’s no K3 or IC-7800 but I like it!
Personal Computer: Quad-Core @ 3.2Ghz using Dual boot Windows 7/Ubuntu
Software: N1MM Logger, MMTTY(RTTY), FLdigi(PSK) and Ham Radio Deluxe. MMTTY and FLdigi works within N1MM
Soundcard Interface: SignaLink USB. This is used so I can send Voice CQ and AFSK from the digi programs
Headset: Heil Pro Set
Antenna(s): G5RV, ButterNut HF9V (Not Used Yet)
Amplifier: Heathkit SB-200 w/ 600w out (Not Used During a Contest…Yet). This is optional and can change your category

Contests I’ve actively participated in (So Far)

Various Field Days (1995-2011) – Even though it not considered to be a contest, I think it is! Field day with the MTARA, PRA and HCRA
New England QSO Party (2011,2012) – Actually won a plaque for winning first place in Hampden county in 2011. It also means that I beat 6 other ops. Doesn’t matter, still won. Single Op from home using low (1oow) power, submitted as high power by mistake.
CQ World Wide SSB (2011) – 144,026 points. Would have had more if my power didn’t go out (Oct storm). I’m still getting logbook of the world confirmations from this contest
CQ World Wide CW (2011) – 12,000 points. My goals were to make 100CW contacts which was achived. I used a computer for the contest so I was only able to make contact with strong stations that were also using a computer. This contest gave me a push to learn CW
ARRL 10M contest (Dec, 2011) – Approx 8,000 pts. Spent only a couple of hours operating as I don’t have very good 10m coverage (Dipole in attic)
North America QSO Party – (Score Unknown) Participated in NAQP from K1TTT contest station using the call NE1C.
CQ WPX SSB – Approx 10,000,000 points. Multi-Op From K1TTT using call NE1C. Was the only op on the night shift for the second day. It was a slow night making abt, 100,000pts but when Europe opened on 20M, I made around 1,500,000 points in the first couple hours. Had a great time, I wish it was my call being used from the stations. I worked countries that I never even heard (Thailand, Mongolia) from at my QTH.It was pointed out that there is more pride making contacts from your home QTH and your setup which I fully agree.

(ARTICLE STILL UNDER REVIEW)

My SB-200 Project – Update 1

Well, after a month or so of operation with the SB-200, my first “oops” happened. I went to turn on the amplifier and I thought I had everything correct and when I went to TX I heard a loud “Pop” sound. Quickly shut off the amp and disconnected the power. Opened the case to find that one of the resistors and the parasitic suppressors popped. I knew something was going to happen because the resistors were turning black.

Since I had to fix the suppressors, I figured this was the time to do some other “Modifications” to the amp. When I first rebuilt the amp, I ordered all the parts to do almost all the mods that you see on KL7FM’s SB-200 Page. I figured since it’s opened up, this would be the time to do SOME of those mods listed on his site. Are these mods needed?.. Nope! If they were then I would assume that they would have been incorporated a long time ago. I just figured if it makes it run a fraction of a percent better, why not invest the extra couple of dollars.

First thing I did is replaced the Parasitic Suppressors and I also replaced the .001uF 1kV ceramic Disk cap with a .0025uF 10kV disk cap (as seen in orange in the picture above),
Apparently it allow less RF to leak back into the power supply on the lower bands. Cap was around $2.00US

In this photo I replaced the two 33ohm carbon resistors that I had with some higher wattage metal oxide resistors. I then replaced the 3300Ohm resistor with a high wattage metal oxide type as well. I also replaced the 2 200pF caps with 4 470pf 1kV. I guess by replacing the caps, there will be decrease the grid-to-ground reactance for better improvement on the lower bands.

In this photo I replaced the nylon protected wire for the input to the cathode and replaced it with a 10Ohm 3W resistor. I guess this will help dampen the VHF oscillations as well as help by prevent over driving the amplifier.

After hooking everything up, The amp turned on and sprung back to life. After messing around with it for a couple house, I haven’t really notice really any improvements. doesn’t mean nothing is happening which is WAY better than having it break on me. So it was a success.
Since the AMP has been operational, I’ve notice that it gets very hot with little use. My gut is telling me that the Pancake AC fans are not doing the job efficiently. The fins are quite small and most of the room is taken up by the motor in the center. I am seriously considering the purchase and installation of a replacement of the type of fan originally used in the SB200. The company that sells the fan kit want over $60 and I am still tossing it around in my head. So far I keep my eye on the temp and I’m using a bigger fan that sits on top of the case to exhaust the heat. |
When the time comes to install the new fan, I am also going to do more modifications that were on that website that have to do with protecting the power supply and the meter. I might even go as far as replacing the meter light with an LED that turns Red when I’m TX. I also might change the “REL Power Sense” POT with a Switched POT so I can put the AMP in standby mode. Hopefully after this, I will never have to go in that amp ever again!

My SB-200 Project

I felt that it was time to put some “Fire In the Wire”. However I wanted to learn about amplifiers since I have no clue how one really works other than giving my signal a boost. The original plan was to build one from scratch but after some attempt at collecting parts I decided that building one from scratch was not going to work out since I didn’t have knowledge to even start one. The next best thing was to buy an amplifier and rebuild it.

I ended up getting a Heathkit SB200 Amplifier. The reason I went with the SB200 is that it appears to have a huge following and (some) parts are still being sold for it. There are also many articles written about this amplifier and it’s still being used in a lot of stations to this day.

SB-200 Main — Here it is! Ain’t it purty! Arhajrhajr

What is an amplifier and what does it do? Or what does an RF amplifier do since we’re dealing with RF (Radio Frequency). A RF amplifier is a electronic device that takes a low-power radio frequency signal and turns the signal into larger signal with more power without changing the characteristics of the signal . This can be done by at least a couple of different ways. It can be done using Vacuum Tubes or Field Effect transistors (FET) which act very different but produce similar results. Vacuum tubes use High voltage with low amperage and FETS use low voltage with high amperage. There are many different types of amplifiers that are divided into classes depending on the type of circuitry used in the construction and its final use.

Do you really need an amplifier? This question could lead to a lot of debate between hams. There are hams that take pride on making all their contacts by only using the power provided from the transceiver (and some using under 10 watts/QRP) and there are hams that prefer using amplifier at almost all times. It all depends on your situation and needs. I would prefer a nice antenna setup that can be directed and have gain over a amplifier but at this point in my life, it’s very unlikely that it will happen. I went with an amplifier as a “Pile-Up” buster. An example for me is when 9K2UU (Barrak in Kuwait) was on the other day. There were so many people trying to contact Barrak that it felt impossible that I was going to establish contact with him. The last time he was on I tried for over an hour to make a QSO without luck. Mostly due to the other operators using Amplifiers. This time I had the amplifier so after a couple of times of trying to contact him, I turned on the amp and made a QSO with Barrak with the first try.

So how does the SB200 work. We know it takes the signal from the transceiver, amplifies it and sends it out to the antenna. But how? The SB200 has three areas that make amplification possible. You have the power supply, input circuit and the output circuit. There is a relay that is controlled by either a switch or the transceiver that activates the amp. The signal comes out transceiver into the “Input Circuit of the amp. The input circuit consists of coils and capacitors that are adjusted and controlled from the band switch on the front panel that provide the tubes with the proper impedance. The signal then passes through the tubes where amplification takes place using the components in the tubes and the very High voltage provided from the power supply to power the tubes. After the tubes do their work the signal passes through the “Output Circuit” consisting of more capacitors and Coils to clean up the signal even more and is fed to the antenna. This is just a basic summary of how the SB200 works. There are websites that explain how amplifiers work in great detail and I’ll link to them at the end of the article.

Now to my SB200. I found this amp on the for sale section on QRZ.com. The amp needed work and thought that this amp would be the perfect project to get my feet wet in amplifier building. Thing about Heathkit amps is that they are kits. They are as good as the person that built the amp. If the original builder had no clue what they were doing (examples are cross wiring, swapping components and poor soldering to name a few), the amp will perform poorly if it performs at all.

SB200 Box — This is the box my SB-200 came in!

The seller did a poor job at packaging the amp for shipping and my pants almost turned brown when I saw the box come off the truck. The seller then blamed me since “I didn’t pay enough for shipping” when it was the seller who gave me the shipping quote. The amp showed some signs of damage from shipping which appears to be cosmetic but I was worried about the High voltage power supply so I hooked it up to find that I was getting the 2300-2400vdc that I needed. A bit of relief. I’ve learned to inquire how the item is going to be shipped from now on.

When I got this amp it was in the middle of being restored. There were no tubes, the components were missing on the tube sockets and there were no parasitic suppressors (Which I was well aware). It appears that previous owner replaced the original cooling fan with a couple of PC type fans and installed a “Soft-Start” circuit as well as “Soft-Key” circuit but removed the “Soft-Key” before it got to me. The power supply that provides the High Voltage also appears to been replaced/upgraded. Since this amp was designed back in the 1960’s where the circuit that activates the amplifier used -110vdc. It would ruin modern transceivers keying circuits by putting high voltage into the transceiver. To combat this people install a “Soft-Key” which basically converts the -110Vdc to around 1Vdc which plays nice with the modern transceivers. Another modification that was done before I got the amp was the addition of a “Soft-Start” module that prevents a “Rush” of current hitting the tubes. when you push the on button, the amp is supplied with a load that is restricted for a couple of milliseconds and then switches to the full load using resistors and relays. Even though I’ve read on many sites that the “Soft-Soft” is not really needed for this amp but since it’s installed, I’ll keep it. It can do no harm.

SB200 Fans, Soft Start and Soft-Key — The fans (top), Soft-Key (Left Green Board) and Soft-Start (W/ Expoxy glue on the top in-case it gets detached and bounces around(

The previous owner also shipped some components that will make bringing this amp back to life a lot easier. I received the filament choke and a couple kits from AG6K (Not sure if he still sells kits) with detailed instructions on installation.

The New Parasitic Suppressors. Accidently wound of the coils with an extra loop. Thought it wasn’t a big deal… WRONG!

The only thing I have to do is obtain the rest of the parts. The tubes were available from RF parts. The tubes were about $120 for the pair, A new “Soft-Key” kit for around $30 from Harbach electronics and the rest of the components were about $20 from Mouser. I have around $350 invested in this project.

SB200 572B Tubes — Show me the tubes… SHOW ME THE TUBES!

After all the parts came in. I found a manual with a schematic online and used it to install all the missing parts and installed with “Soft-Start”. After installation of the parts I went back to the manual and double checked the entire installation and everything seemed to check out.

SB200 Grid Circuit — All new components! However it looks like a nest and needs cleaning

Before turning the amplifier on, I preformed some checks to lower my chances of a smoke and/or light show. The manual states to perform a couple of “Resistance” checks. The first one is to put a multimeter on the anode clip (nipple of the tube) and the chassis. When the meter stabilizes, it should read around 180k ohms. However I was seeing 240K ohms which made me a little bit worried. After searching google I learned that this is due to the replacement of the High voltage board. The other resistance test is to place an ohm meter on lug 3 (V3) of the tube and place the other lead to the chassis. The resistance should be somewhere between 5k-15k ohm. I ended up with 10K which is right in the middle.

After performing all the checks I can do with the amp off, I was still hesitant on turning the amp on since I never really messed around with an amplifier before. I wanted the amp to be checked out by someone else but I got impatient one weekend and decided to go for it. I removed the tubes from the amplifier and powered the amplifier. To my relief there was no smoke/light show and was still seeing around 2400v on the meter. I turned the amp off and waited till the caps were discharged. Placed the tubes in and turned the amp back on. To my amazment, the tubes sprung to life and produced a comforting glow. I left the amp on for an hour and nothing happened in that time so I decided to put a signal through the amp to see what happens. I went on the 20m band, put the radio into CW and did a tune. I was glad to see around 600W on my watt meter.

I decided at that point to make some contact with the amp on. Spinning around the dial I hear a Northern Ireland DX station and threw my call out. He responded to my call the very first time and gave me a report of 59 20+. That made me a very happy operator to know that my amp was working.

SB200 Tubes — Let there be LIGHT! Hmmm electric sex.

The only place where I have 220V that I can get to was in the basement. So that’s where my equipment was until I had the chance to get 240v wired to my office. Once in my office I wanted to really use it so I turned it on and went through all the check to find that I was not seeing any grid current show up on my meter. That started to scare me so I shut the amp off and went searching for the answer to “What’s causing this to happen?” I asked the HeathKit Amps Yahoo group and I also asked help from my local club. There was a major block in the road and it seemed that the help I was getting was leading me to nowhere. Some people said I have shorted tube(s) and others said that something is wrong with the wiring. Both can be plausible since I never really worked on an amp and I’ve heard of people receiving bad tubes. But then someone ask me if I had a dummy load. Of course I don’t! So another member of the club let me use his Oil can dummy load. When I hooked up the dummy load I noticed everything is now looking good.

I now have a working amplifier! Just in time for the ARRL DX SSB contest. I was happy that I was going to get to use my new amplifier and put it to the test. On Sat morning well into the contest I decided to start. Amp on and 20m is quite busy. I was making a good amount of contacts while only searching & pouncing until I started to hear a sizzle sound coming from the amp. Found out that one the resistors in the parasitic suppressor kit has become broken and was arcing to the resistor it broke from. That kept me out of the contest till I had the nerver to solder it back together and get back on towards the end of the contest.

I still have some issues but I am leaning toward my antenna setup to be the cause. For some reason the tubes get very hot on 80 and 40m. I would have to either get a tuner that can handle the power or get a resonate antenna before I can continue on other things. I am also thinking that the PC type fans are not doing their job. The chassis and case get hot to the point where I can’t touch it. Tubes are not glowing but I want to keep it that way.

SB200 J-Clips — The original pressed in PEM nuts are long gone. The rubber feet that should screw into here holds the entire unit together. Found that Tinnerman (J) clips work great

Future plans for the amp are the following

New HV board – The one I currently have is newer that original but I think if I’m going to keep this amp that it should have a new board
Glitch Resistor – This will save the tubes if anything goes wrong with the HV board.
Meter Protection – Since the meters are rare and get expensive when they come up for sale, I’d rather spend a couple cents on some diodes.
LED Meter Conversion – I want some nice white/bluish LED to light up my meter to match my FT-950
Various upgrades – There are websites out there that have a ton of things to do to this amp to make it much better. I already got the parts for most of the mods but want to make sure the amp is fully functional before I even attempt modifying the amp.
New Chassis, Cover and face – I want to design a more modern looking case around the same chassis and incorporate some more RFI shielding and better ventilation and the use of a thermostat for fan operation.
Clean Up – When the new chassis is made I would like to DE-oxidize all connections, coils and plates.

Some cool sites I cam across when rebuilding this amp
Rick Measures (AG6K) – Boat loads of AMP info
Yahoo groups – HeathKit HF Amps – Helped me out a couple times, worth joining
Robert Norgards (KL7FM) SB200 page – I plan on doing almost all his suggestions

SEE UPDATE #1 SINCE THIS ARTICLE

SEE UPDATE #2 SINCE THIS ARTICLE

Congrats to the New Hams and upgrades!

Congratulations to those who attended the Ham Radio Classes at the Moose Family center in Chicopee MA. It was great to see a lot of people interested in either getting a license or upgrading to a general or extra.

Rich, N1KXR is in the middle of teaching a class

The classes seem to go okay. It’s pretty difficult to cover all the sub elements with the time that we have but everyone stuck around and put their best foot forward.

We now have

9 New Technicicans
9 New Generals
5 New Extras

Some of the new generals started off with no license at all and it’s great to see all the hard work pay off. There were some who didn’t pass what they wanted to get but it’s not the end of the world. You have the book, and there are a lot of places you can ask questions for the areas you’re having trouble with. If you stick with it, you’ll have your license or upgrader sooner than you think.

From a VE Standpoint, It was the Biggest VE exam I’ve taken part in. It started off real slow as the candidates we’re all testing but then a big surge of tests started coming in which made for a busy afternoon.

Overall it was great. I’ve learned a lot about how these classes go and If I have the chance to do it again, I most likely would.

Hope to hear all the licensees on the air

Homebrew 5 Element VHF Yagi

Okay, enough of UHF/GMRS antennas. Now it’s time to step it up (just a little bit) and fabricate a bigger antenna.
Due to material, I decided on a 5 element Yagi built for VHF since all I would have to buy is more 3/8″ round stock. I’ve taken what I learned from the GMRS Yagi and applying it to the design and fabrication of this VHF Antenna. I am writing this article in a way in which I hope newer hams can understand, build and learn about antennas. So please excuse if I go into details about things that you consider simple and “common sense”.

In order to design a Yagi we have to learn what a Yagi is. A Yagi is a Directional antenna made of up elements.

The 3 Major parts which make a yagi are the driven element, reflector and director. When cut and placed at a calculated distance (On a Boom), the elements will cause the RF (Power) to be sent (radiated) or received in whichever direction the antenna is pointing to. In the radio world this is a great because you can basically “Focus” the power and direct it in the direction you want. Whereas a Vertical (Omni-Directional) radiates its energy in a 360 degree pattern (think of throwing a rock in a still lake and watch the ripple pattern in the water.) which will send out your signal “everywhere” but will dissipate quicker.

On the lower frequencies (HF), a Yagi would be the antenna of choice by Hams. Well then how come every ham doesn’t have a Yagi (on HF)? There is a couple of down sides to having a Yagi or Beam antenna (on HF). First off, HF Yagis are huge. In order to use a Yagi/Beam to it’s fullest you would have to install an antenna tower/mast and rotor. HF Yagis are expensive and so is the tower and rotor, so the parts alone could add up to couple thousand dollars. I’ve seen cases where someone moved or is SK (Passed on) and sold their equipment cheap. There are also several other factors that would steer someone away from a Yagi. Those factors could be age, housing restrictions, living in an apartment, permits, handicap, property size, neighbors, and more stuff than I list. However the Yagi I’m building does not take much space and could be transported to be used in events where I am portable. Yagi’s come in many different sizes depending on the frequency and the efficiency of the antenna. The lower the frequency, the larger the antenna. The higher the frequency, the smaller at antenna. The length of the antenna will vary depending on how much efficiency/gain you want. Increasing the length (boom) and adding more director elements will increase the gain/efficiency of the antenna. On the Yagi that I am building, the design is based on the length of the (boom) antenna rather than the gain.

So you want to build a Yagi. To start off your going to have to know what material your going to be using. Most Yagi antennas are built using Aluminum since it’s light and is a great conductor (Well, compared to steel/stainless). There are many different types of aluminum and I would say that 6061-T6 Aluminum would be the best choice for antenna building. The reason is that 6061-T6 is more weather durable and easier to work with compared to other aluminums. The downside of 6061-T6 is when it comes to bending. 6061-T6 tends to crack when bending using a tight radius. Since we’re not bending anything on the yagi we’re building then It won’t matter. If it comes to other designs of yagis that use a Hairpin or folded dipole then I would take the type of aluminum into consideration.

Okay, we’re using Aluminum. What’s next? Now we need to figure the sizes of the material we’re going to use. This all depends on personal preference. For HF Yagis, you’re going to need Tubing ranging from 2″, telescoping in diameter down to 1/2″ because the antenna is going to be big and will need to support the weight of the elements. Since we’re dealing with smaller VHF/UHF antennas, the material doesn’t have to be large. For the antenna that we’re building we will be using 3/8″ (.375″/9.5mm) round solid aluminum and 1″ (1.00″/25.4mm) square tubing to mount the elements to. You can also use 1/4″ solid round aluminum instead of the 3/8″ to save a couple of dollars but realize that it’s easier to damage 1/4″ rod. If you decide to go with 1/4″ round please note that the dimensions and calculations you see in this article will NOT work using 1/4″ rod because 3/8″ rod has more surface area for the signal to travel on and all the calculations are made with 3/8″ In mind. You can change it to work with 1/4″ which I will cover later on.

Now that we have the material and size in mind that we’ll need, we now need to know what frequency we want to transmit on. Since this is a VHF yagi that we’re building, it will most likely be in the 144-148 range. Are you going to use this antenna for sideband (ssb/usb) only, or both ssb and FM (repeater/general operation)? Reason I ask that is if your designing this to be on sideband only, you will only need it to design it to work best over the span from 144.000Mhz to 144.500Mhz whereas FM would need to be designed over the entire band (144.000mMhz to 148.000Mhz). Since we’re building an antenna for the entire 2m band, we going to use 146.000Mhz as the design frequency since it’s directly center of the band and would allow for a somewhat even performance throughout out the band.

Another downfall of the Yagi is that it has a narrow bandwidth.What I mean is that the antenna will work the best over the span anywhere from 100khz to 10mhz depending on the design (Could be more or less). If you start transmitting out of that span, it could create signal loss and high SWR causing the transmitter to step down power to prevent damage (or actually damage older radios). Why build an antenna that is not going to radiate the power going to it? If the antenna is designed and fabricated correctly and you have at least a SWR Meter/Bridge then this should not be an issue.

So now we have everything we need to start designing a Yagi-Udi Antenna. Well… How do you design one? This is a fork in the road and there are many different ways you could design one (too many to list). There are different programs for different types of Yagis and there are different mathematical formulas for different (or the same) types of yagis. The method I am going to use is a Antenna modeling (software) program called 4NEC2. This program is based off the Numerical Electromagnetics Code for modeling antennas. The great thing about 4NEC2 is that you can model almost any antenna and the best part is that its FREE! What this software allows you to do is to design/draw an antenna using X,Y,Z Coordinates and then run the antenna through a simulator to see it’s efficiency, SWR, impedance and many other things that I have yet to look at. Basically it will tell you if your antenna is going to work and how well it will work on or near the frequency you designed it for. Another great thing about 4NEC2 is that it will perform adjustments on your antenna to optimize it for the best results. So if you are somewhat close to a good antenna, the software (if the programed right) will make it even closer. This software however is slightly (or very) difficult to use for a new person in the hobby. I adapted to the design portion of the software because I have knowledge in CAD (Computer Aided Drafting), but I had to do a lot of reading about the electrical properties and how to make the software do what I want. I am not going to dive in depth explaining this software. However, I will show you how I used the software to create the antenna. If you find the software to difficult then skip the section and use the final results in building your antenna.

Before we start using the software, we’re going to need to know what dimensions to input in the software. We can’t just throw random numbers into the software and expect magic to occur and produce the “Perfect” Yagi antenna. The U.S Department of Commerce and the National Bureau Of Standards released a document which helps in Yagi Design. Information based off the manual has lead to the following Dimensions

300 (speed of light in meters)/146.000(mhz) = 2.0547 wavelength or(WL) (in meters). This will be used as reference for the following dimensions.

Length of each element as follows:
Reflector Length = 0.493 X WL=1.01297m (or 39.880″)
Driven Element Length = 0.473 X WL = 0.971873m (or 38.262″)
Director 1 length = 0.440 X WL = 0.904068m (or 35.593″)
Director 2 length = 0.435 X WL = 0.893795m (or 35.188″)
Director 3 length = 0.430 X WL = 0.883521 (or 34.7843″)

Spacing of each elements from the reflector as follows (WL = 2.0547 in meters)

Reflector to Driven element = 0.125 X WL = .256838m (or 10.1117″)
Reflector to Director 1 = 0.250 X WL = .513675m (or 20.223″)
Reflector to Director 2 = 0.500 X WL = 1.02735m (or 40.446″)
Reflector to Director 3 = 0.750 X WL = 1.54103m (or 60.670″)

Now that we have all the dimensions that will put our Yagi in the “Ball Park” of a good VHF Antenna. The software will end up fine tuning the elements and spacing between elements to obtain the best SWR for the giving variables (i.e Element diameter, Boom length and etc).

Open the 4NEC2 and plot the antenna using the dimensions above. At some point in the near future, I will post a video on how I plotted the antenna. If you don’t know how to use 4NEC2 I suggest searching using google for results because that’s how I learned.

Please note that using the “Optimization” will give different results what I came up with. So do not get alarmed or worried. If it was done right then there shouldn’t be any issues to the design that the software gave you. DO NOT START CUTTING ANYTHING!! These dimensions will change!

Here are the Dimensions and spacings from 4NEC2 that I got! (Note that these dimensions will be the ones used for the rest of the article and that they will be different than your results if you decided to use the software)

Spacings (Each from the reflector)
S1 =12.469″
S2 =20.492″
S3 =37.933″
S4 =58.000″

Element lengths
RL =40.495″
DE =38.363″
D1 =36.056″
D2 =36.086″
D3 =34.074″

Now you should have all the Dimensions (lengths) of the elements and the spacing. Now we need to work on the BOOM. The Boom is the tube that we are going to mount the elements on. At this point we have to decide what material, size and length we’re going to use for the boom and how we’re going to mount the elements. I have decided on 1.000″ square aluminum tubing because it’s commonly used and that it’s easier to work with compared to round tubing. The length that we’re going to need is based on the location of your last (furthest away) director.

I also decided to mount the elements by drilling through the boom and using plastic shoulder washers so we can slide the elements through the boom without the elements contacting the boom. At any point we DO NOT WANT THE ELEMENTS TO CONTACT THE BOOM!! Because we’re putting the elements through the boom, the elements will become electrically shorter because of the inductance change. So we would have to increase each element which is called “Boom Correction”.

There is a formula to calculate the “Boom Correction”. In fact, there are many different formulas to calculate the correction so I am going to use the one that I see most on the internet

C= (12.597B) – (114.5B^2)
The C equals the correction, and B equals boom diameter in wavelengths. This formula will work on boom diameters smaller than .055 wavelengths (Smaller than 4-1/2″ boom diameter on VHF and smaller than 1.5″ boom diameter on UHF). So let’s dissect this problem to make it easier.

To find B we’re going to need the wavelength of the frequency (146Mhz) that were going to use in millimeters.
300/146 = 2.0547 meters or 2054.7 millimeters.

Now we need to take the boom diameter in mm (1.0″ = 25.4mm) and divide it by the wavelength (in MM) of 146Mhz
25.4/2054.7 =0 .012362 (B is .012362)

Now we can do the problem
(12.597*0.012362)-(114.5-(0.012362*0.012362))=.138226

Now we take the correction and multiply it by the boom diameter (in MM)
.138226X25.4 = 3.510mm or .138″ is out correction

We now have to ADD .138″ to EACH element. So our NEW element lengths (in inches) are as follows.

RL = 40.633″
DE = 38.501″
D1 = 36.301″
D2 = 36.224″
D3 = 34.212″

At this point we should have all the lengths of the elements, spacing distances from the reflector to each element, boom diameter, boom length and the type of material we’re going to need for fabrication… Right?

We need to go shopping before we build. Here is a list of what we need to build

5ft (60″) of 1X1″ Sq Aluminum tubing (1/16″ Wall/Thick)
16ft (192″) of 3/8″ Round Aluminum Rod

I would suggest that you google for a local “metal supply” shop. I would avoid the big chain stores (like Home Depot, Lowes) or stores that have every type building material under one roof because the markup on material is very high. I was able to purchase 12ft of sq tubing and 24ft (2 12ft lengths) of rod for around US $30. There was enough material to build this antenna and two UHF 3 Element beams.

8pcs – 3/8″ Inside Diameter Plastic Shoulder Washer
6pcs – 3/16″ Inside Diameter Plastic Shoulder Washer
1pcs – 3/8″ Inside Diameter X 3/4″ Diameter X 1-1/2″ Long Plastic Spacer

These Items will be a little tricky to get. If you’re in the US, you can go online and order from a company called McMaster Carr. I have the part numbers listed on the blue prints that I’ve used. However when I put the antenna through the ringer (tests), I will see if I have to change the part numbers to something else. I have been considering using plastic rivets instead of shoulder washers because I am afraid that the adhesive (epoxy) will not hold the plastic shoulder washers to the boom. If you get different washers or insulators, The dimensions will differ from what I have on my blue prints, so please change dimensions accordingly. If you do order through McMaster Carr, They will only sell the washers and spacer in packaged amounts. If I recall the small shoulder washer came in a pack of 100pcs, the larger shoulder washers came in a pack of 50pcs and the Spacers came in a pack of 10. It’s great because I ended up making a bunch of antennas w/o having to make an extra order.

Glue or epoxy.

Anything that you know will bond plastic to metal and will survive the elements (rain, cold, ice, snow, heat, wind). Still a good idea to use even if your using plastic rivets.

6pcs – 9/16″ Long #8-32 Screws

I would suggest using stainless steel screw as it will survive in the elements longer

There are optional things that you buy like Sq caps for the boom and vinyl caps for the ends of the elements for water and safety protection.

There is some more paper work to do (Grrrrr). Now that we have all these neat numbers and material, We should at least have some kind of drawing to help us when it comes to actually cutting, drilling and tapping these parts. I assume that your building the antenna for one or two reasons which are that you either don’t have enough cash to purchase a commercially made (and tunable) Yagi, or that you actually want to learn how these types of antennas work. So let’s take some more time to layout the antenna so we can have something to use when we’re cutting, drilling and tapping.

I am going to use software called “AutoDesk Inventor 2011” which is a 3D design software that is used for CAD (Computer Aided Drafting) purposes. This software will let me make each part in 3D and assemble all the parts to make sure of proper fitment. This software will also let me create Blueprints based on the information I typed into the software. If you can’t get your hands on any type of this software, no worries. You can do the same thing on graph paper.

My Results are posted below. Please note that I’ve included all the information that is needed IN the Blueprint for those who just want to download the prints and fabricate w/o reading this article. However the information listed on the prints (other than the dimensions) have only basic information for experienced fabricators/ antenna builders.

**** INSERT BLUE PRINTS ****
(Still working on them, please check back)

Now that we have all the dimensions and a print, LETS GET FABRICATING!

Here is a list of basic tools that are needed. Most Hams have these tools or can get access to them. Following this list will be a list with the preferred tools that would make the job faster, smoother and more accurate. However the majority of people do not have a lot of the items

Basic Tools Suggested:

Hacksaw
Measuring Tape
Marker
Drill
*Various Drill Bits (Ranging from .125″ to .750″)
8-32 Bottoming Tap (With T Handle)
Bench Vise
Sandpaper (120 grit)
Scratch Awl/Scriber/Etching pen (or anything that has a sharp point that you can easily handle)

Preferred List Of Tools

Metal Chop Saw (With vise)
Vernier Calipers (6″ or bigger)
Automatic Center Punch
Marker
Drill Press (With a vice able to hold SQ and Round tubing/stock)
*Drill Bits (Various to .750″ [or 3/4])
Files or deburring device

* – For those who don’t have .750″ drill bit, depending on where you live, a 3/4″ Drill bit can get expensive. I would suggest either a step bit (still expensive) or a 3/4″ countersink (at 82 degrees). Drill the specified hole up to the biggest bit and then finish it off with the 3/4″ countersink. Since it’s aluminum, it will not damage the countersink and you will be able to counter sinks holes on other projects (DO NOT COUNTERSINK HOLES ON THIS PROJECT!

Lets start off by cutting all the aluminum rods (elements) and tubing (boom) to the correct lengths by using the tape measure. The blueprint posted in this article shows both decimal and fraction to the nearest 32nd of an inch.

(elements shown cut to size with a band saw)

After you cut the elements and boom to length, It’s time to layout the hole pattern on the boom and each element

I used a red pencil to mark the location along the boom. Then I marked the center of each location using a pair of verniers and used a marker to make the center point more visible.

When marking the elements it’s a good idea to mark the center point twice. Once from each end so you know that your exactly on center of the element. With the driven elements, you just need to place a mark at 3/16″ in from only one edge.

Using a drill or drill press with a small (>.125″) drill bit. Drill pilot holes on every center mark on the boom. DO NOT DRILL THROUGH THE BOOM! Only drill through the side you marked unless your using a bridge port mill that has a perfect 90 degree head.

Also drill pilot holes at the marks of each element. Once again, DO NOT DRILL THROUGH THE ELEMENT! You will only want to drill half way through the element. A bit of advice is to measure from the tip of the drill bit 1/4″ up and use the edge of some masking tape to tell you where to stop when drilling. If you feel un-easy about drilling the element, you should have a couple of inches of scrap rod that you can test both drilling and tapping on.

This photo shows pilot hole being drilled into the boom

This photo shows the Pilot Holes drilled in each element

After drilling the pilot holes, time to open the holes according the blue print. With the elements, I suggest using a .120″ (or #31) drill bit as the element could wobble causing the hole to open up a little more. With the boom I would start with opening the holes where the elements slide through first! Then switch to the 3/4″ bit and open up the holes where the driven element slides through. Switch back to the pilot drill bit, insert the plastic spacer that will hold the driven elements and using the two holes on the top of the boom as guides and drill halfway through the plastic spacer. Then open the rest of the holes to the correct size.

The next step is to tap each element with a #8-32 bottoming tap. If you can get your hands on a bottoming tap, you can take a regular tap and break the head off it and grind/file it flat.

This photo shows a element being tapped. Try to make sure your tap is 90 degree and straight.

After everything is cut and drilled and tapped to size. It’s time for assembly. Assembly is pretty stright foward.
Glue/Epoxy all shoulder washers/rivets into place and let dry. The driven elements are going to slide into the plastic round spacer. Make sure that each side of the driven elements does not come in contact with each other. Then slide in the reflector and directors and secure them with the 6-32 screws. When finished I placed more epoxy around the elements (NOT THE DRIVEN ELEMENT) at the point where they meet the boom. I did this because I don’t plan on taking apart the antenna.

Attache your coax to the driven element making sure you don’t have the connections contacting the boom.

You should hopefully have a functional 5el VHF Yagi

Here are some reading I’ve taken with a analyzer that I borrowed.

At 144.42Mhz, I got a 1:1 SWR with an Impedance of 48ohm.

At 146.02Mhz, I got a reading of 1:1 SWR with an impedance of 46ohms

At 147.72Mhz, I got a SWR of 1:1 and an impedance of 44Ohms
These readings were taken in my house with the antenna mounted to a wood broom stick. When I got the antenna into the attic I took another set of readings before I gave the meter back and I saw that a slight change on the values. Can’t wait to get it outside.

If you plan on making your own Yagi, please take ALL SAFETY considerations into effect. Know and respect all the tools you are using and when it comes to installing your Yagi, make sure the antenna with not come in contact with any utility lines.

If you are using the plans from this page, please note that your results may/will vary from what I’ve made. Since I’m new to antenna making, I would not want you to risk any material/money. Please confirm your findings with someone who does know before purchasing or building. These are just my notes on what I did to create an antenna.

Sources Of Information:

Peter P. Viezbicke, National Bureau Of Standards. “Yagi Antenna Design”. U.S Department of Commerce/NBS Tech Note 688 (Dec 1976). PDF (Sept 2011)

G.R Jessob, and R.S. Hewes. “Radio Data Reference Book” (ISBN: 1872309305) Radio Society of Great Britain; 6th edition (November 1995)

Unknown Author (N4UJW?). “Basic Yagi Antenna Design For The Experimenter”. YAGI ANTENNA DESIGN BASICS. Web (Sept 2011)

Martin Steyer (DK7ZB). “DK7ZB Yagi – 144Mhz-Yagis”. DK7ZB Website. Web (Sept 2011)

ARRL, R. Deam Straw. “The ARRL Antenna Book: The Ultimate Reference for Amateur Radio Antennas, Transmission Lines And Propagation.” American Radio Relay Leauge; 21st edition (May 2007)

Peter Knott. “Wire Antenna Modelling with NEC-2”. Antenna Engineer 8/12/2009. PDF (Sept 2011)

Daniel C Lester (KE9SE). “The Effects Of A Conductive Boom On Element Lengths”. VHF-UHF Basics (9/17/2009). Web (Sept 2011)

Guy Fletcher (VK2KU). “Effects of Boom and Element Diameters on Yagi Element Lengths at 144, 432 and1296 MHz”. ARRL QEX Magazine (Jan/Feb 2000).

Software Sources:
Arie Voors . “4NEC2” – Web – (Freeware) Program Used to Design and Simulate Yagi (and other) antennas
Autodesk Corp. “Autodesk Inventor 2011” – Web – (Trial/Edu/Paid) Program used to Design and create blueprints

Happy New Year!

Just want to wish those who visit this site a Happy New Year. I haven’t been able to post many articles but that will change and stay tuned. I recently acquired a Heathkit SB-200 that needed some work so I’ll defiantly have a write-up on that. I also fabricated a 5EL VHF Yagi which I will show you step by step on how I designed, fabricated and tested (somewhat) the new antenna. And there is a possibility of my first HAM related home-brew equipment that I’ve seen in QST. It’s in the planning stages but I think it’s going to happen.