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Author Topic: Starting At Amateur Extra  (Read 14528 times)
KB1WSY
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Posts: 672




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« Reply #15 on: March 12, 2012, 03:00:17 PM »

>>... building a better solid state direct conversion receiver...<<

Sounds like a great idea, but I am sticking to my original mad plan of staying with tube technology and homebrewing it all from scratch (no kits). The Ramsey was the only exception that I made to that rule because I knew the homebrew plan was going to be time consuming and I wanted to get familiar with how QSOs are conducted and also to practice copying CW. Today I made further progress (with the souped-up Ramsey) and copied some CW DX from Europe. I'm only getting bits and pieces but I'm able to monitor callsigns and disjointed words, not yet complete sentences, at about my speed (15wpm) or slower. Doing it with the Ramsey is probably excellent practice because the selectivity is terrible for CW so I'm hearing all these QSOs piled up on top of each other and learning to focus on just one of them for copying! Listening is great fun, and an essential skill for the future given that my future homebrew receivers will be nowhere near "state of the art."

A couple of months ago I was in Anaheim at a business convention (I'm in the music products business) and during a break in the proceedings, took a 5-minute taxi ride to the nearby Ham Radio Outlet. So I walked in in my suit and tie, looking very middle-aged and appearing much more affluent than I really am, and told the salesman I was getting interested in ham radio after a 40-year break (and I also mentioned my interest in CW). I was immediately steered to a diminutive black box from ICOM with a price tag on the top of about $3,000. I was flabbergasted by what this thing could do: the waterfall display, the DSP filters, the automation of just about everything. But it also left me cold, and so did the super-automatic keyer that looked to my eyes like the paddle was gold-plated! Amazing stuff, but not for me. And I'm not just talking about the price tag; serious homebrewing can be quite expensive, as I am discovering, especially if you are interested in the tube end of things and are serious about getting a full tool kit and test equipment. Buying a modern rig (or a modern kit) would probably cost me a lot less, in the long run!

73 de Martin, KB1WSY
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N2EY
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Posts: 3856




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« Reply #16 on: March 14, 2012, 05:48:50 AM »

Sounds like a great idea, but I am sticking to my original mad plan of staying with tube technology and homebrewing it all from scratch (no kits).

(cure Montgomery Burns voice)

....excellent.....

given that my future homebrew receivers will be nowhere near "state of the art."

But what does "state of the art" really mean anyway? AFAIC, it's really just a marketing buzzphrase about 99% of the time.

I was immediately steered to a diminutive black box from ICOM with a price tag on the top of about $3,000. I was flabbergasted by what this thing could do: the waterfall display, the DSP filters, the automation of just about everything. But it also left me cold, and so did the super-automatic keyer that looked to my eyes like the paddle was gold-plated! Amazing stuff, but not for me. And I'm not just talking about the price tag; serious homebrewing can be quite expensive, as I am discovering, especially if you are interested in the tube end of things and are serious about getting a full tool kit and test equipment. Buying a modern rig (or a modern kit) would probably cost me a lot less, in the long run!

Well, yes and no.

For one thing, new rigs tend to depreciate rather quickly. That $3000 box won't be worth that much 10, 20 years from now. Even if its price stays the same, inflation decreases the value.

(Fun exercise: Look up what old rigs cost back-when, then plug the values into an inflation calculator. I use the Westegg one (google "westegg inflation"). It's almost scary how much ham gear used to cost, in inflation-adjusted dollars.)

IMHO the real key to homebrewing is to always be on the lookout for useful stuff at a good price. Including good ideas, like the BC-453-and-converter one.

You really don't need a lot of tools for homebrewing tube stuff - if you have patience, time and a little ingenuity. Plus skill. Take it from somebody who has cut 3 inch meter holes in a 1/8 inch panel without a drill press, punch or circle cutter.

73 de Jim, N2EY
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KB1WSY
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Posts: 672




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« Reply #17 on: March 14, 2012, 08:58:47 AM »

>>Including good ideas, like the BC-453-and-converter one.<<

Indeed, although I have now perused so many BC-453 design ideas from QST, CQ, General Electric Ham Club, Stoner's book, and the separate thread on this forum, that there is some data overload. Finally came to the conclusion that all of these designs are flawed, one way or another, as far as my purposes are concerned (multiband coverage of the CW ham bands without image response problems). So this morning I finally decided to (1) start very, very simple with the original 80/40 Stoner circuit from 1956, but (2) if I later add additional bands, do some of the design myself rather than slavishly follow one of the 50-year-old designs and in particular, design and build my own tuned circuits so as to break loose from the "unobtainium" problem that is particularly serious with any kind of vintage inductor.

It seems that a well-performing multiband converter needs (1) a serious RF stage in front of everything, (2) double conversion within the converter, making the entire receiver chain triple-conversion once the BC-453 is added, and (3) judicious choice of IF frequencies for maximum image rejection. Stoner's "Sideband Handbook" design initially seems to fit that bill, and so do some of the QST designs, but severe limitations emerge once you look deeper into most of these circuits. Stoner's "ingenious" system for using both the fundamental and the harmonics of the crystal is too clever by half, and leaves out the CW sub-bands. I tried doing the math for a CW-band version but it always seems to require multiple crystals, not to mention the issue with the new WARC bands.

In fact I am leaning toward using the simple "converter" for a while and then, in the fullness of time, building a more "coherent" high-performance receiver that doesn't depend on the BC-453. Anyway, I think that I will have fun with the supposedly "simple" converter design, many months of fun both building and using it.

BTW yes I know that in radio-speak it is the 3rd harmonic not the 2nd, but as you now know, I am in the music business and thus, you put your finger on the source of my confusion! Cheesy

There is possibly some room in the ham book market for a book on "homebrewing tube gear in the 21st century." It would span the spectrum from "authentic" gear that uses strictly salvaged or NOS parts at one end of the spectrum, to designs that (in the spirit of the DIY movement) involve making your own coils and other parts that are hard to find or expensive (dials, for instance). The nearest thing I have found is a really fun series of six little books called "The Impoverished Radio Experimenter" published by Lindsay publications. It is amazing what that guy built: his own IF transformers from scratch (using big carboard boxes lined with aluminum foil and the discarded carboard rolls from paper towl packages as the "coil form"), his own slide rule dials, even his own air-variable capacitor. If you search the Internet you can find a lot of this kind of thing -- hams are amazingly inventive. But there doesn't seem to be a modern, overall *compilation* available.

73 DE Martin, KB1WSY
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KF2UJ
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Posts: 2




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« Reply #18 on: March 14, 2012, 01:38:48 PM »

I went on the fast test route back in 2004, got my advance license within 3 months and did not get on the air until last month for the first time with HF. So glad to see someone else besides me worrying about making a fool of themselves on the air.
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N2EY
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Posts: 3856




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« Reply #19 on: March 14, 2012, 02:27:12 PM »

I went on the fast test route back in 2004, got my advance license within 3 months and did not get on the air until last month for the first time with HF. So glad to see someone else besides me worrying about making a fool of themselves on the air.

How'd you get an Advanced in 2004? FCC stopped issuing new Advanceds in April 2000.

73 de Jim, N2EY
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N2EY
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« Reply #20 on: March 14, 2012, 02:52:02 PM »

Finally came to the conclusion that all of these designs are flawed, one way or another, as far as my purposes are concerned (multiband coverage of the CW ham bands without image response problems). So this morning I finally decided to (1) start very, very simple with the original 80/40 Stoner circuit from 1956, but (2) if I later add additional bands, do some of the design myself rather than slavishly follow one of the 50-year-old designs and in particular, design and build my own tuned circuits so as to break loose from the "unobtainium" problem that is particularly serious with any kind of vintage inductor.

ANY practical design has flaws. The question is whether you can live with them or not.

The W6TNS design is pretty good if you make the following changes:

1) Use a bigger chassis. No reason to cram everything together. Sure, his version looks really neat, with the power supply on the '453 back porch and the little converter, but it leaves no room for experimenting, parts substitution, etc. Plus those precious power supply components are tied up to one job.

2) Use two independent variable capacitors rather than a 2 ganger.

3) Use your own coils. #26 or so wire on plastic pill bottles works well.

4) 4050 kc rock for 80 CW, 7550 kc rock for 40 CW. Or thereabouts.

5) If you want the higher bands, you need even more tuned circuits to eliminate the images. A dedicated converter for 20 has been done, and could be adapted for 30.

It seems that a well-performing multiband converter needs (1) a serious RF stage in front of everything, (2) double conversion within the converter, making the entire receiver chain triple-conversion once the BC-453 is added, and (3) judicious choice of IF frequencies for maximum image rejection. Stoner's "Sideband Handbook" design initially seems to fit that bill, and so do some of the QST designs, but severe limitations emerge once you look deeper into most of these circuits. Stoner's "ingenious" system for using both the fundamental and the harmonics of the crystal is too clever by half, and leaves out the CW sub-bands. I tried doing the math for a CW-band version but it always seems to require multiple crystals, not to mention the issue with the new WARC bands.

If you want a "serious" all-band rx, you have to go beyond the BC-453. I have some ideas on the subject.....

In fact I am leaning toward using the simple "converter" for a while and then, in the fullness of time, building a more "coherent" high-performance receiver that doesn't depend on the BC-453. Anyway, I think that I will have fun with the supposedly "simple" converter design, many months of fun both building and using it.

It's a question of balance...

At one end of the spectrum is the extremely simple design that works poorly, but is easy and quick. At the other end is the complex design that works well but requires an enormous amount of time and resources to build. The trick is to find the balance between them.

One big mistake I see beginners making is that, because their rigs and licenses allow lots of bands and modes, they want to do all of them. So they put up a very compromised multiband antenna, and then struggle. Much better to focus on 1-3 bands and 1-2 modes, and a setup that does them well, and work up.

In the bad old days, we Novices didn't have that problem, because the license was so limited.

BTW yes I know that in radio-speak it is the 3rd harmonic not the 2nd, but as you now know, I am in the music business and thus, you put your finger on the source of my confusion! Cheesy

You'll confuse a lot of folks if you use the wrong terminology.

There is possibly some room in the ham book market for a book on "homebrewing tube gear in the 21st century." It would span the spectrum from "authentic" gear that uses strictly salvaged or NOS parts at one end of the spectrum, to designs that (in the spirit of the DIY movement) involve making your own coils and other parts that are hard to find or expensive (dials, for instance). The nearest thing I have found is a really fun series of six little books called "The Impoverished Radio Experimenter" published by Lindsay publications. It is amazing what that guy built: his own IF transformers from scratch (using big carboard boxes lined with aluminum foil and the discarded carboard rolls from paper towl packages as the "coil form"), his own slide rule dials, even his own air-variable capacitor. If you search the Internet you can find a lot of this kind of thing -- hams are amazingly inventive. But there doesn't seem to be a modern, overall *compilation* available.

Such a book would be great, but it's a monumental task because:

1) All sorts of copyright issues
2) Have to weed out the good ideas from the bad.
3) Massive amounts of info to sort through and decide what's worthwhile to include and what isn't.
4) You will always miss something really good.

Years ago I collected all sorts of books, magazines and info. That's still doable but not as necessary as it used to be.

What can be done today is to set up a "Radio" folder in your computer, and whenever you find something interesting, save it, scan it, etc. Set up subfolders however you want.

For example, in my "Radio" folder there's a "Tubes" subfolder, with various subfolders in it. Whenever I see a tube manual or datasheet online that I find interesting, it goes into there. Another folder is "Rig Manuals", another is "Articles", another is "Surplus", etc.

Of course it's important not to spend too much time downloading!

But in a relatively short time you can build up quite a "library".

For example - want a Handbook from the 1930s? The Radiotron Designer's Handbook? Pete Millett's site has them. Original manual for the BC-453? On BAMA mirror site.

And lots more.

73 de Jim, N2EY
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KB1WSY
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Posts: 672




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« Reply #21 on: March 14, 2012, 04:01:06 PM »

Jim, thanks again for your helpful comments. Just went over to the HBR site and saw your photos and description of the homebrew receiver you made from scavenged parts including the salad bowl for the dial.... always reassuring to know that someone has been there before! Also saw your impressive current "hollow state" homebrew lineup ("Southgate 7" and so on) on your QRZ profile. Are you in the electronics business or are your skills entirely a byproduct of your hobby and interests?
 
I was actually thinking of using a junked 45rpm turntable as a circular dial (from one of those old portable record players). These are reasonably heavy and have a good smooth bearing, although I am not sure how the bearings hold up if you use the turntable in a vertical orientation. The other idea I had was to fasten a CD-ROM or a 45 RPM record on the front of the BC-453 dial, with a dial printed on label paper glued to it, until I realized that the small tuning knob gets in the way and makes that impossible.

In terms of the ultimate homebrew receiver, I think I am several years away from having the skills to build that. Best to do things bit by bit and have fun along the way. I have stashed away an Eddystone 898 dial, to give me the motivation eventually to build a receiver worthy of having it grace the front panel!

Do you know whether anyone published a project for a homebrew tube Wadley loop design? Have you tried doing one of those? It seems like a very clever scheme, especially the way that it nulls out frequency drift. I know that some solid state receivers such as the Yaesu FRG-7 as well as the old Racal RA-17 radios were Wadleys but I haven't seen a homebrew one. As for conventional sets, the "heavy hitters" in the published "tube homebrew super receiver" stakes seem to be the Crosby HBR series and the ARRL DCS-500, but there must be plenty of others.

73 DE Martin, KB1WSY
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N2EY
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« Reply #22 on: March 14, 2012, 06:47:45 PM »

Just went over to the HBR site and saw your photos and description of the homebrew receiver you made from scavenged parts including the salad bowl for the dial.... always reassuring to know that someone has been there before!

Actually a plastic cereal bowl. That receiver was from the Southgate Type 4 series. Built in the 1970s when I was a penniless EE student.

Also saw your impressive current "hollow state" homebrew lineup ("Southgate 7" and so on) on your QRZ profile. Are you in the electronics business or are your skills entirely a byproduct of your hobby and interests?

I was a ham before I entered high school. One thing lend to another, but I don't do radio as a "profession".

I was actually thinking of using a junked 45rpm turntable as a circular dial (from one of those old portable record players). These are reasonably heavy and have a good smooth bearing, although I am not sure how the bearings hold up if you use the turntable in a vertical orientation. The other idea I had was to fasten a CD-ROM or a 45 RPM record on the front of the BC-453 dial, with a dial printed on label paper glued to it, until I realized that the small tuning knob gets in the way and makes that impossible.

That's doing it the hard way.

When I first built the 453/converter setup, all I did was to make some pressure-sensitive labels (on a typewriter!) that had the 80 and 40 meter frequencies, and stuck them on the BC-453 dial. They could be peeled off if ever needed. For example,

3500
7000

went over the "550" marking.

3550
7050

went over the "500" marking, etc.

In my later experience with the BC-453/converter, it didn't take long before I could do the mental arithmetic without even thinking about it. 550 on the 453 dial was the low end, 500 was 50 kc up, etc.

It doesn't have to be fancy.
In terms of the ultimate homebrew receiver, I think I am several years away from having the skills to build that. Best to do things bit by bit and have fun along the way. I have stashed away an Eddystone 898 dial, to give me the motivation eventually to build a receiver worthy of having it grace the front panel!

Do you know whether anyone published a project for a homebrew tube Wadley loop design? Have you tried doing one of those? It seems like a very clever scheme, especially the way that it nulls out frequency drift. I know that some solid state receivers such as the Yaesu FRG-7 as well as the old Racal RA-17 radios were Wadleys but I haven't seen a homebrew one. As for conventional sets, the "heavy hitters" in the published "tube homebrew super receiver" stakes seem to be the Crosby HBR series and the ARRL DCS-500, but there must be plenty of others.

73 DE Martin, KB1WSY

The problem with esoteric designs like the Wadley loop is that they require a lot of design and test to get working right, and may have unforeseen behaviors. I prefer the KISS principle; make the rig just as complex as it needs to be to do the job, but no more.

Because I like contest operating, and because I found a Heathkit CW filter for $5 at a hamfest, my main interest since about 1980 has been hollow-state CW transceivers. The Type 7 which you see in the photo is actually a transceiver, just spread out over a couple of chassis. It was built in the early 1990s, and replaced the Type 6 which was built in the very early 1980s. The only sand-state devices in the entire Type 6 and Type 7 transceivers are two 1N34 diodes in the SWR bridge in the Transmatch. Everything else is hollow-state.

IMHO, the 898 is a nice dial, but it is only good if matched to a very good capacitor (like the Jackson) using the special Millen 39016 Oldham anti-backlash coupling. And a good chassis design. Some serious metalwork.

I take the easy way out. The ARC-5 transmitters have a very good capacitor/dial assembly, all ready to go. Or get a capacitor from a BC-221 frequency meter.

The best of the Ancient Ones' designs were done, IMHO, by W2LYH. Look up his QST articles, particularly the receiver. Bob is gone now, but he really knew his stuff.

73 de Jim, N2EY
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W3HF
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« Reply #23 on: March 15, 2012, 05:06:58 AM »

How'd you get an Advanced in 2004? FCC stopped issuing new Advanceds in April 2000.
Probably just a simple misstatement.

According to the ULS, KF2UJ was last renewed in 2004, but was granted at least as early as March 1994. VanityHQ shows his previous call, N2PHQ, active in 1992, and no record of KF2UJ prior to 1993.

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KD4LLA
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« Reply #24 on: May 08, 2012, 07:19:21 PM »

Will this result in an obligatory change of callsign

No need to change.  I am three states and two classes ahead from when I started.  An Elmer once told me once you change your callsign it just isn't the same.  So I have kept my original novice 4-land call.  I don't know what it "sounds" like in CW, as that was never an interest of mine anyway.  And I can remember some of the folks who had following sequence licenses (LLB, LLC, LLD), as we studied together.

Mike
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W8ASA
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« Reply #25 on: June 15, 2012, 08:18:06 AM »

This has been a great thread. Thanks for starting it. You mentioned that you may be a CW-only operator. In that case, once you get your Extra, look around to see what call signs are available, and consider picking one which has a relatively short CW signature... the fewer dits and dahs you have to send, the easier it will be. I would LOVE to have, for example, n5ee, or ne5e, or ae5e, as opposed to one of my former call signs WB6QWF, which, in comparison, took a lot longer to send and receive than my current W8ASA.
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THEDESERTTORTOISE
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« Reply #26 on: July 09, 2012, 04:12:49 PM »

Just a quick antenna idea to get by until?  I'm waiting to buy some materials for two antennas. One is either a hexbeam or moxon design, while the other is an 80 meter loop. The reason for this post is that I went out and bought the 14 gauge insulated wire I wanted to use on the 80 meter loop and a used 50 ft tower so far. Because of the l shape of my property I'll need quite a few risers (masts) to get my loop up to the 20 or 30 feet I want. I've been running my HF off of an end fed 54 foot wire and an 80 through 6 meter mobile antenna... both were so so.. Well, long story short... I was working 40 meters one day and just finally got fed up with not being able to be heard. I took the 300 feet of insulated wire I had and strung an ugly loop all around the yard. I think it's 6 feet off the ground at it's highest and has about 18 sides to it. It loops through lock hasps on the garage, hand holds on the RV's, around slats in the fence, and just about anyplace I could tuck it. I threw my analyzer on it... low impedance across the bands, and off I went. I've since been able to talk as far as French Polynesia and some Europe. Funniest part is I had been listening to this great station out of Calgary Canada for days and had never been able to break through the pile up to talk to the guy. Got through the first try with my mess of a loop. So.. if you have enough room try a loop. The longer the better I think... they're really friendly impedance wise. With a heap of insulated wire it can hang almost anywhere. And what I really like is they hear well. Good luck on the projects and 73's, K5ATE
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K8AXW
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« Reply #27 on: July 17, 2012, 09:03:58 AM »

WSY:  Have fun with all of the reading you've asked for!   Cheesy

One of the great things about ham radio is the many facets it has.  In your case, you can enjoy ham radio for the time being from an education standpoint while at the same time planning and scrounging parts for your homebrew gear.

In my case, I've used ham radio for 55 years as a means to test and use the many pieces of homebrew gear I've made.  In other words, homebrewing is the facet of ham radio that I enjoy.  I do enjoy a ragchew but building is MY thing.

Enjoy!  Stay in the books...... and keep building.
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