Antennas

[skier]

@-mjk- I would very much appreciate that offer - thank you! However, i should be clear so as not to exploit your generosity, my needs are for a broadband amp. So if this is what that is and I can go from, let's say, 160M to 15M or 10M like the Ham amps do, that would be great. (Some even go 160 - 6 M.) But if it's a true transmitter, then it's likely focused on one band or part of a band (I presume the AM broadcast bands), then it may not be usable because I presume I would be inputting audio to modulate the AM carrier. I need it to be able to linearly amplify various transmission modes to be able to use it for AM, USB, LSB, etc.) I'm not currently into CW, FM is limited to 6M and up, and that really only leaves the digital modes - I may pursue them in the future, but don't need to concern myself with these other factors for this purchase.

MJ, I don't mean to place limits on your kind offer, I just want to be precise in letting you know for what I'm searching so you don't call in favors or such on my behalf with something I couldn't pursue. In other words, I don't want to waste any of your time, but really do appreciate your offer and possible help. Thanks again!

 

[Arjan P]

OK, there is one small thing I notice.. You guys use 'M' for meter, but M is the prefix for Mega, while 'm' is the base unit for length, meter (or the prefix for milli)... Sorry, couldn't help myself

 

[-mjk-]

@Arjan P you are absolutely right. Thanks for pointing that out!

 

[skier]

@Arjan P You are, of course, correct. I knew that, but for some reason, I've come across a number of articles that have been using an uppercase 'M' and I seem to have picked up the bad habit. 'M' is also used for million as in $3M dollars or for 1,000 in Roman numerals while 'm' is used for mile, minutes, and likely much more.

Thanks for the correction - I prefer to use words properly.

 

[-mjk-]

I think a lot of the old ham radio literature uses the capital M for meter.

 

[skier]

Thanks MJ - we definitely needed a good excuse.

Well, I'm going to bed and you're up for the day. I'll catch you on the flip side.

 

[-mjk-]

Speaking antennas: My friend Grady has a new article out. He was part of a design team that came up with a new antenna design and it's probably going to save the North American AM radio market.

https://radio-guide.com/

His article starts on page 6.

 

[skier]

Thanks for that! I'll read it today.

 

[skier]

@-mjk- Thanks for that link - that's a great article and I love the magazine also - never heard of it before. I didn't stop to think that existing broadcast radio was also going digital beyond SiriusXM, but I should have. With TV having converted over 10 years ago and Ham modes such as FT8, JT65, PACTOR, and many more, I should have know that conventional AM and FM couldn't be far behind or could even be already here. It's even difficult to think of AM in any form being truly high fidelity with extended frequency response, true and enhanced stereo, and low noise, but again, I should have known or at least anticipated. I found Grady's article very interesting!

Thanks for the wake up!

 

[-mjk-]

Remember, it's just spectrum. The AM broadcast band is a holdover from the days when radio was developed. I've been fortunate to work on numerous multi-tower arrays as a field engineer (I've done dozens of field intensity studies). The main drawback is the large wavelengths that require big towers and big spaces. Now that the HEBA system is operational that will change the game.

Jerry, you're gonna love this video:

Shot in 1989, I was 33 years old in this video (I'm 65 now, lol). Scott, WB1F shot this video of us operating commercial station WILD's tower, loaded up for 160m by Grady Moates. We found local ham op W1LD (now, SK) who is also seen in the video. The main shot of us 3 at the operating desk are:

1. Left: Steve, NQ1F, genius designer who made the bandpass filter for the beverage antenna and the 160m RF preamp.
2. Center: Me, NV1L, team leader.
3. Right: John, WN9T, snake antenna designer/builder, and contesting software engineer. Also, the homebrew tuner for the beverage that John built is visible on top.

We have a lot of collective contesting experience, and several of us personally know several world-class Russian contesters, and they all send at 20 WPM. That seems slow, but it totally eliminates the need to repeat due to QRM, etc. obliterating high speed CW.

Later in the video, I do a walk around for Scott and I describe how we set things up and are operating the contest station. I'm wearing a blue shirt and I have my industrial safety glasses on (we were doing some mod work previously).

Dell Hood, W1LD tells how he found out about WILD by getting a record in the mail, lol. Now deceased, he lived to be over 100 years old. In this video, he's over 80 and sharp as a tack, cutting jokes all night. His best one was as he was leaving: "Well, I guess I'd better go while there are still some coats left."

In the overview shot near the end you can see WILD's main transmitter (3 cabinets) and to the far left, their 1kw backup transmitter.

The next year, John, WN9T build a 2 wire steerable Beverage antenna.

There are several conversations going on simultaneously, lol.

Scott, WB1F is a Massachusetts constable: Melrose Cyber Center - Constables

Grady Moates is one of the most respected broadcast engineers in North America. His website is loudandclean.com. An accomplished musician, he's the only person I know (besides me) who turned down a major label recording contract. Please check out this video of Grady, singing backup for his close personal friend, Todd Rundgren:

Grady is on the far right, standing to Todd's left in the video.

 

[skier]

MJ, this video is great and what you guys were doing using a 259 foot commercial AM broadcast station antenna in Boston overnight during their off-hours to pump a 100W Ham transmitter operating on 160m is one of the coolest things I’ve ever heard!. Man, I wish I had seen this early this morning before I headed out to a Ham exam session. I’m being asked to become a VE and thought I would spend some time seeing just what’s entailed before committing. To be honest, it’s not that interesting, but the fact it helps others come into the ranks is important (especially if we want to keep our allocations) and I’m planning on doing this. But we were chatting before and after the exam session and I’m sure they would have been amazed to hear about this. If this happens often, I’ve never before heard about it.

Thanks for sharing both the story and the video!

Does Grady live here in the north east?

 

[skier]

Well, I was able to answer my own question: Hyde Park, MA. I also found a video of Grady being interviewed over a year ago re: the HEBA system. My mouth almost dropped when he started speaking about how he got into radio by building an Allied Radio Knight-kit for his own radio station when he was 15 and then later getting a job as a radio engineer. I found it particularly exciting because I built my first AM radio transmitter at about the same age.

Unfortunately, I had no kit and instead worked off a schematic in a book I got from the library. My dad did some TV and audio servicing on the side, so I had access to wire and tools, I had several old radio chassis from thrown-out radios and audio amps I scrounged from people's trash (yes, a form of dumpster diving at such a tender age). It took me months to get all the components, not a problem for the resistors and capacitors - what I couldn't scrounge up in values, voltage (caps) or wattage (resistors) from old TVs, they were available new from the local Lafayette electronics store and the tubes from any TV service business. Though, I had to save my money from my TV Guide route to get enough to buy new parts.

But my real problem was coils - I couldn't find what I needed and didn't know how to emasure an inductance value if it wasn't printed on the side. Finally, an old TV tech (yeah, in his 60s, our age group... SHEESH) gave me a book I still have today entitled: "The Inductance Authority". It has tables and graphs and gave me enough info to wind my own coils, like coil form diameter, number of turns for a certain size wire, what it equated to in inductance, etc. Though, my first attempt used wire too small and I burnt out my first coil.

Anyway, without belaboring my own life story any longer, it was exciting to go down memory lane and find Grady started out quite similarly to me, but he became famous, and me? Well, I do know that I'm well known on this forum by at least 4 or 5 other members. that's something, right?

 

[-mjk-]

Yes, Jerry, you are well known on this forum and also you are mentioned in the same posts as Grady.

I met Grady on Halloween night, 1980, at a party. He had a Hammond M1 with a Leslie that he wanted to sell. I bought it from him. He had put a tape switch across the bottom of the top tier keyboard so all one had to do was bump it to change the Leslie speed. Grady has done all kinds of cool stuff. But the one thing that you will not read about him is his generosity. I cannot count the number of times he has helped me out with everything he could, in so many ways.

That's a very interesting story about how you grew up messing around with radio. My father was the first color TV tech in the state of Florida, when he moved the family there in 1959. Although interested in radio, I didn't really get into it until I met Grady. He brought me into the business, which led to me having my own radio career, including a national talk show in the mid 90s. Grady has spent considerable time on the air himself and he has at least 1 gold record single given to him for promoting "Roundabout" by Yes.

I hope you can find a young person to pass that book along to. That's how you leave your legacy behind, by helping others.

When I left Boston there were virtually no young people who were interested in becoming broadcast engineers. I have no idea where the new engineers are coming from nowadays. We use to joke that for every engineer who retired, they would be replaced by 2 lawyers. That doesn't seem so funny now though.

 

[skier]

Ha! A Hammond M1 with a Leslie, huh? Yeah, you and I still have more in common to discover. I have a Hammond L111 and Leslie that I bought in the 70s - it's in my studio today, but I rarely use it because Hammond simulation plug-ins are so good and so easy to use; I also don't like the rumbling sound of the Leslie at the lower volumes at which I prefer to record. I suffered some hearing loss due to the loud playing of my rock bands in my teens and twenties and I don't want it to get worse. (No tinnitis, and I don't want it.) The main difference between our stories is that I didn't buy my Hammond from anyone so interesting, and have never seen the seller again since the purchase.

Referring back to my transmitter construction, I remember the article said to not use an antenna longer than 10 feet or I would exceed the FCC power limit. Well, I ran that sucker with as long a wire as I could find, and then incrementally soldered additional wires onto that. Between each addition, I played a reel of tape recorded songs to modulate the transmitter and took my bike out for a ride with a transistor pocket radio (remember them?) to see how far away my signal could be heard. I'd ride further and further with each antenna length increase to reach my goal of blanketing the town with my stupendously great broadcast. BUT, each additional increase seemed to make less and less of a distance increase and it never really got to be more than perhaps 500 or so feet - an 1/8 of a mile ain't much. When I look back, I think the transmitter I built created more of an inductive field than actually radiated a signal. Whatever the reason, polite society was saved.

 

[skier]

You know, I do think that fewer people are going into broadcast, at least radio, just as fewer are becoming Hams. However, there is good trend in that new recruits are at least into building circuits with the likes of Arduinos, Raspberry Pies, Edisons, and a plethora of micro-controllers as well as IoT projects. So at least new blood is again becoming interested in electronics, which is a good thing because it's a very important part of the future.

 

[skier]

I hope you can find a young person to pass that book along to. That's how you leave your legacy behind, by helping others..

True, that book and more. I've accumulated excess tools and equipment also and am now dragginggggg... my son-in-law and some of my nephews into electronics whether they like it or not... well, I hope they're liking it.

 

[-mjk-]

True, that book and more. I've accumulated excess tools and equipment also and am now dragginggggg... my son-in-law and some of my nephews into electronics whether they like it or not... well, I hope they're liking it.

That is great! They'll thank you later.

 

[-mjk-]

MJ, this video is great and what you guys were doing using a 259 foot commercial AM broadcast station antenna in Boston overnight during their off-hours to pump a 100W Ham transmitter operating on 160m is one of the coolest things I’ve ever heard!. Man, I wish I had seen this early this morning before I headed out to a Ham exam session. I’m being asked to become a VE and thought I would spend some time seeing just what’s entailed before committing. To be honest, it’s not that interesting, but the fact it helps others come into the ranks is important (especially if we want to keep our allocations) and I’m planning on doing this. But we were chatting before and after the exam session and I’m sure they would have been amazed to hear about this. If this happens often, I’ve never before heard about it.

Thanks for sharing both the story and the video!

Does Grady live here in the north east?

Jerry, I was an ARRL VE for years. I'm also a W5YI VE (which never expires). It's a good thing to do to help the community. You could even do ham radio classes over Zoom to help people pass their first test. If there are no tests in your area, you could set up a test session with your own team. I have no idea how to handle in-person testing with the current situation, but eventually things will return to some semblance of normal.

One night I was bored so I went out to the base of the tower and loaded it up directly on 80m with my tuner from my shack. A guy in Canada told me I was the loudest thing on 80m at S9+20, lol. Having a tall tower to work with is fun!

 

[skier]

I'd not heard of W5YI - I'll look it it up.

The FAA and FCC limit tower height to 200 feet if you're 5 or more miles from an airport. A Ham can request a higher height if he's willing to provide other information so the FAA can place the tower's location on the sectional maps we pilots use. In your case of using a broadcast tower, the tower is already approved and the tower is usually higher than 200 feet just due to the 1/2 wavelength height needed for a good impedance match for AM band frequencies. I'd never heard of anyone doing that and I'm still amazed.

I've visited many antenna sites over the years and I particularly like antenna farms. I'd contact the chief engineer, let him know what I do for a living, that I have a GROL, and they've always invited me to come and given me a great tour of their facilities, including the transmitter building and the doghouse. Most of us really like what we do and sharing it with someone of like interest is great. Unfortunately, 911 changed all that and such openness is no longer the norm.

Last summer, I took my girlfriend to the base of a TV tower with a height of 630 feet HAAT that I had visited decades ago. The facility is now nothing more than a PBS repeater and I thought she would want us to leave in a few minutes. But surprisingly, she spent considerable time looking up at the tower and asking questions - she confided that evening that she found it more interesting than ever she thought she would and marveled at how big the tower was at its base, that it had an internal ladder, etc. Now, if only that tower was insulated from the ground (it's not; it's severely grounded with multiple 4/0 [~250MCM] bare copper cables) and I could connect to it, I suspect I could actually work the 630m band with a matching network. I doubt many Hams work that band, and we're limited to just 1 watt, but it seems it'd be a cool experience. There's something about using a high tower that feels so appealing, at least to us nerds.

 

[-mjk-]

Jerry, very cool! Quick reply about loading up grounded towers: use a slant-wire feed. Climb the tower and find the 50 ohm resistive point and attach. Then just cancel out the reactance and you're good to go! That method allows you to use your grounded ham tower (beam, vertical, etc.. and all) as a radiator for the low bands.