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Author Topic: My First-Ever QSO, 50 Years Late -- Entirely Homebrew  (Read 492 times)

G3EDM

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My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« on: August 27, 2021, 02:53:55 AM »

Today I had my first-ever QSO, with a ham in Germany.

This was nearly 50 years after I first passed the UK Radio Amateurs' Exam in December 1971. Long story, but procrastination is the main reason it took me so long to get on the air.

I am posting this in the Homebrew forum because my rig is entirely homebrewed, from ARRL designs of the 1960s, and many helpful people here on eHam helped me as built these projects, mainly in a concentrated burst about seven years ago. It is that rig I am using on the air today.

That station is described in the 1968 edition of ARRL's "How to Become a Radio Amateur". The receiver is a three-transistor set with a regenerative FET detector. The transmitter is a MOPA (6C4 and 5763) with about 12 watts plate input. The antenna is a homebrewed full-size wire dipole. I am operating monoband on 40m for the moment.

My first-ever QSO was this morning, with a ham near Bremerhaven, Germany, a distance of about 590 kilometers (370 miles) from my QTH in southeast England.

Inevitably, the transmitter needs to be tweaked. A knowledgeable ham in Sweden heard a distinct "yoof" in my crystal-controlled signal this morning, and advises adjusting the trimmer capacitor that is between the grid of the oscillator tube and ground.

So it goes, in an unending cycle of building, improving, troubleshooting, building again. For me that's the fun in ham radio, but actually operating makes it all worthwhile!

73 de Martin, G3EDM

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NI0C

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #1 on: August 27, 2021, 04:21:00 AM »

Congratulations, Martin!
I've been following your journey in these eHam forums for a while now, and am very pleased to hear of your first QSO.
Although I am not a purist home brewer, I have experienced the thrill of building kit transceivers (two Elecraft KX1's and a K-2) and making QSO's with them.
73 & happy operating,
Chuck NI0C
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W9AC

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #2 on: August 27, 2021, 05:45:56 AM »

Martin,

Well done.  Don't stop now...

I had a peek at your homebrew gear and the layout looks nearly identical to the original gear as described in the ARRL publication.

My start in 1972 required me to homebrew a transmitter.  My OM had his own equipment, but he insisted that I construct (and use) a transmitter under his tutelage.  It's a 6DQ6A-OD3-5U4 design from the 1958 ARRL Handbook.  Nearly all parts were cannibalized from an old B&W TV set that sat in the corner of a dark basement.  FT-243 crystals were ground on plate glass to the desired operating frequencies. 

The transmitter still lives today, operated annually during the ARRL's SKN event.   

Paul, W9AC
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K6BSU

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #3 on: August 27, 2021, 09:36:59 AM »

Most people study and try to pass the FCC test just so they can quickly get on the air for some radio fun.  I can't imagine a gap of 50 years,  However, home-brew equipment, no matter how humble, makes radio operating that much more exciting.
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G3EDM

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #4 on: August 27, 2021, 09:40:58 AM »

It's a 6DQ6A-OD3-5U4 design from the 1958 ARRL Handbook.  Nearly all parts were cannibalized from an old B&W TV set that sat in the corner of a dark basement.  FT-243 crystals were ground on plate glass to the desired operating frequencies. 

The transmitter still lives today, operated annually during the ARRL's SKN event.   

Paul, W9AC

My next transmitter project is from "Understanding Amateur Radio" (ARRL 1963) from what, at the time, would have been old TV parts. Five bands, crystal control, about 60 watts. 6K6GT oscillator, and a couple of 6BG6GAs in parallel for the PA. Outboard power supply. I already have most of the parts.

But it is jostling for priority with two other key projects: (a) my first superhet receiver to replace the regenerative Novice radio, and (b) obviously, a VFO. Awfully hard to put those in any kind of preference order! I also have most of the parts for those projects.

The biggest challenge is that since moving to England from America three years ago, I've been living in a much smaller home with almost no room for the shack, let alone proper workshop space. But I am working on finding a solution to that conundrum....

73 de Martin, G3EDM
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K8AXW

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #5 on: August 28, 2021, 10:49:01 AM »

Martin:

Congratulations!  I too have been following your 'career'/efforts to get on the air. 

I still have my "How To Become a Radio Amateur" book acquired at Ft. Devens in 1954.  It replaced my original copy that I bought several years before 1954.  To me it was the main inspiration to becoming a ham.

A couple years ago I built the one-tube, crystal controlled "built on wood slats" transmitter from this book. I have it setting on my built-from-scratch 1400w linear amplifier.  Sort of like the beginning and end.

Perhaps your next project should be like wooden boxes stacked on a light duty two-wheeled hand cart.  It can be your shack and work bench all in one which you can conveniently move around as necessary.

Again, congratulations Martin!

73

Al - K8AXW
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A Pessimist is Never Disappointed!

G3EDM

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #6 on: August 29, 2021, 01:55:39 AM »

I still have my "How To Become a Radio Amateur" book acquired at Ft. Devens in 1954.  It replaced my original copy that I bought several years before 1954.  To me it was the main inspiration to becoming a ham.

I have three editions of this book: 1954, 1968 and 1974. By the 1970s, the ham on the cover looks like me at that date (long hair) but I don't remember having an admiring YL in my shack, pointing at the middle of the Atlantic on a globe of the world, as that photo shows!

One of my weird projects is to build the stations featured in all the editions of the book, and see how they compare with each other in terms of easiness to build, performance and so forth.

I've spent the day so far both operating (calling CQ for hours, no answer yet) and troubleshooting the chirp that some of my contacts are hearing on my signal. There are several suspects, and possibly just caused by one dodgy crystal, but it's an important one (7030kHz).

I'm playing with the grid-to-cathode trimmer capacitor in the Pierce oscillator circuit to try to tamp down the oscillation a bit, so far no luck. It wants to oscillate very vigorously regardless of crystal used, and may be over-driven. I opened up the 7030 crystal case and it is a modern, smaller crystal that someone squeezed into the vintage FT-243 case sometime in the past.

I bought my large FT-243 crystal collection from a ham who was downsizing and selling his vintage stuff. On further examination now, I see that some of them are totally original and have their frequency stamped on the case, but others have been doctored later with modern inserts and a laser-printed label stuck over the original frequency stamp.

73 de Martin, G3EDM
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GW3OQK

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #7 on: August 29, 2021, 03:47:11 AM »

Hello Martin
I would be more likely to answer your call if you have a chirp because it advertises you as a home-brewer. If you were sending slowly without chirp you would sound like an ordinary beginner using a modern rig. My MO-PA 6V6 transmitter has a nice chirp and drift keying the crystal oscillator.  Are you on 80m?
73, Andrew
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VU2NAN

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #8 on: August 29, 2021, 04:01:04 AM »

Hearty congratulations, OM Martin! Here's wishing you good DX and all the very best!

That's real homebrewing!

My crystal-controlled 20m CW transmitter, built in 1977, was inspired by 'A One-Tube Transmitter for the Novice' (Understanding Amateur Radio - ARRL 1971). The article described an 80m / 40m crystal-controlled CW transmitter utilizing a triode / pentode 6T9.

I used one half of an ECC81 and an EL84. The first contact was a 4X4 (Israel) on a Sunday morning. The frequency was 14.050 MHz and the antenna a ½ λ dipole.

Have fun!

73,

Nandu.

G3EDM

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #9 on: August 29, 2021, 05:22:51 AM »

Hello Martin
I would be more likely to answer your call if you have a chirp because it advertises you as a home-brewer. If you were sending slowly without chirp you would sound like an ordinary beginner using a modern rig. My MO-PA 6V6 transmitter has a nice chirp and drift keying the crystal oscillator.  Are you on 80m?
73, Andrew

Greetings Andrew,

My rig is capable of 80m but is currently hard-wired for 40m. To switch my transmitter to 80m I have to disconnect (un-solder) a tap on the PA tank coil. This is ridiculous, but it is actually exactly conforming with the original ARRL design. My thinking is to alter that so that band-switching is reasonably convenient, probably with a rotary switch hidden under the chassis. I have this weird fetish about not altering the external appearance of the transmitter, which is exactly like the ARRL original!

I have plenty of 80m crystals. My receiver has a plug-in coil for 80m and works quite well on that band.

I do not have an 80m antenna right now. If you look at the Antenna forum here on eHam you will see that I started a thread about this, and there are quite a lot of different ideas for an antenna at my location, which is much too small for a full-size 80m dipole.

For sure, I will be getting on 80m with my existing Novice rig, as soon as I can figure out the above issues.

73 de Martin, G3EDM
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G3EDM

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #10 on: August 29, 2021, 05:25:10 AM »

My crystal-controlled 20m CW transmitter, built in 1977, was inspired by 'A One-Tube Transmitter for the Novice' (Understanding Amateur Radio - ARRL 1971). The article described an 80m / 40m crystal-controlled CW transmitter utilizing a triode / pentode 6T9.

Greetings Nandu! I have that book too, both editions (1963 and the one you have).

There are lots of building projects ahead, as soon as I can figure out how to create a (small) workshop.

It would be amazing to work you one day.

73 de Martin, G3EDM
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VU2NAN

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #11 on: August 29, 2021, 08:00:28 AM »

Sure, OM Martin.

Here's the confirmation of a G3 contact I made in the year 1979.



Unfortunately, OM Peter is no more.

73,

Nandu.

G3RZP

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #12 on: August 29, 2021, 02:02:23 PM »

Martin,

Any tx with just a straight pi network is highly unlikely to meet the current UK licence or CEPT or ITU regulations  -which are tighter than FCC. I would suggest a tuned circuit type antenna tuner would be a very good idea...

vy 73

Peter G3rZP
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G3EDM

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #13 on: August 29, 2021, 02:32:47 PM »

Greetings Peter,

I would suggest a tuned circuit type antenna tuner would be a very good idea...

Or just a low pass filter? I have the parts for that somewhere, along with an American-style empty coffee tin to put it inside....

73 de Martin, G3EDM
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G3RZP

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Re: My First-Ever QSO, 50 Years Late -- Entirely Homebrew
« Reply #14 on: August 29, 2021, 03:21:52 PM »

Martin,

For a 40 m tx, it needs to have a cut off abut 10 MHz.

A tuned antenna tuner using a parallel tuned circuit should suffice instead.

If you need further info, email me at g8on@btinternet.com

vy 73

Peter G3RZP
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