The AM Forum

Hello to all...

This transmitter is a desing from the 50´s ARRL Handbook, its a 6AG7 Oscilator, and a 6L6 or 6V6 for final amplifier, I decide to make one in order to show some local ham friends the joy of "glowbugs" and simple things...

the circuit works nice, and have a nice tone in CW, depends on crystals I can reach 15 to 20 watts output, enough power to cross the country!

...some other pics

Rgds

XE1YZY / Pedro

Well done, Pedro!
I really like simple rigs like that one.

What frequencies are your crystals?

Hi Bill,

on 40 meters I have the following crystals  7,002 -7,010,- 7,025 -7,040- 7,055,- 7,060,  and 7,087 Mhz

73's

Very nice Pedro...Nice selection of parts...You must have a big junk box   You could make a modulator next time...6l6s??  congratulations! 73 un abrazo mi amigo..Steve KL7OF

I like the old buzzard components underneath the chassis.  Dogbone resistor, that's vintage!

I ran the same rig but it didn't look that nice. Graduating to an oscillator / final was a big deal as a novice.

Nice!

I love the pedestal/stand-off mount for the meter!

Greg

Great job!

Simpler is nearly always better.

Hi Greg,

Well it isn't truly a pedestal /stand off, its a towel hanger stilling from my XYL Kitchen, ( she ask me to install it a couple of years a go hi hi)  but looks nice right?

RGDS

I love that lineup! Nice work and we all love the black crackle.

I bult a smaller version up a few years ago- see my avatar - 6AG7 into 6L6 and a Type 80 Rectifier and VR150 regulator. Unbeatable for simplicity and stability.

Mike WU2D

Hi Mike,

Nice work!, the adition of the VR150 is a good Idea I also see a diferent final tank coil, but I am agree with you this circuit works really nice, thanks for sharing Mike!

Pedro

Pedro,
Your rig pictures look great.  Its amazing the satisfaction you can get building and operating very simple rigs. 
I enjoy operating my 1929 TNT breadboard transmitter very much.  You can't get much simpler than this!  A single 210 tube with single frequency control.  I attached a few pictures along with the matching power supply I built for it.
Regards,
Joe, W3GMS

Here are the rest of the pictures...
Joe, W3GMS 

Buzzardly looking key there GMS, pray tell what is it?
I really like the marble base.

Ok, here are my obligatory old buzzard rigs, but I can't claim building rights, just a caretaker.

Hartley UX-210
(http://www.w1ujr.net/images/Hartley%20Oscillator%20W1BSX%201.jpg)

1934 TX - From Bill Orr article - I did finish this one, was not working
(http://www.w1ujr.net/images/1946%20W3GKH%20Rig%20Front%20View_small.JPG)


-Bruce

Looks good Bruce. 
The TNT was built in December 1929 and I became its care taker about 25 years ago.  It runs about 10 watts output and really works well.  I did build the matching power supply for it.  The marble base key is a spark key.  It was given to me by a good friend of mine, Al W3ABN (sk).  He used it and a rotary spark gap back in the spark days.  I have his rotary spark gap as well.  Neat old stuff...
Joe, W3GMS     

Good job Joe, I really like those antique tubes!

My favorite junk box rig- Point was to use "stuff" that was probably not going to be used elsewhere. 6AG7-6V6 modulated by a 12AX7- 6L6

Chris,
Great looking rig buy using parts that you had around.  That was the way it was years ago and its nice to do that today.  Call it your junk box special---"JBS"!! 

It looks like a JT-30 microphone in the picture.  That was the first Mic I had when I first got into the hobby.  I had never seen one with a chome stand.  Mine had a wooden stand.  Did you change out the stand or did they sell a version with a chome stand? 

Joe, W3GMS     

Perfectly balanced rig Carl! You could do a 6AG7 6L6 modulated by a pair of 6V6's and a 12AX7 too.

I added the plug in coil and driver bandswitching later. Here is the rig with the 80M coil.

Mike WU2D

I, for one, have not lost this joy of simplicity (having to work with complex surface mount electronics all day, turning to vintage technology is a great refreshment to me).

I still have 23 years to retirement but when it comes I'm looking forward to spending more time in my lab, tinkering and building stuff that glows!

Yall have really built some nice rigs there.

The year is coming to an end and maybe it has been done before but how about an "AMFONE simple homebrew TX contest"?

Does this make any sense?

rules:

1.)
* Rigs must be built.
* Can be built from parts, assemblies, kits, parts of kits, household items and junk..
* Any rig old or newly built.
* Tubes, transistors, or hybrid.
* Signal circuits and power circuits must be analog. No IC chips or computer stuff or switching power supplies or digital modulation. That is not a simple TX any more.
*Everyone can vote once in a poll. Maximum votes win. That way it's more like members' choice.

2.)
*see rule #1.

Sounds fun - hit those slop buckets with a 50C5.

The 50C5 is the most abused, underrated pube in history. Just think of the abuse your typical AF output tube took in zillions of AC/DC sets.
 
Johnson'd still be making CB's if they'd've put a pair modulated by a pair in their 60's sets.

Indestructable..

Ooops, shouldn't have played them up so much.  The AFools will start scarfing them up.

KT88's.  $205 each.
50C5's  (very rare) 325 each.
 Matched quad, only $1350 (if your supplier can round up that many.)

I don't know if a "contest" is necessary, but I sure enjoy seeing pictures of those nice home brew projects.  Everything from simple "novice-type" rigs to full blown full rack big AM xmtrs.  To me, homebrewing has always been a major part of ham radio.  We can all enjoy seeing how others have approached building stuff and maybe get some ideas for our own projects or become inspired to try similar construction efforts. 

I will try to post some pics of a few of my projects....I would sure enjoy seeing more of the same from other members.

73,  Jack, W9GT

Here are a few pics of the little 50L6 rig.  Using Frank Jones PP osc circuit originally from 1936. Puts out a whopping 3 watts on 40 CW.
AC-DC power supply.  I do use an isolation xfmr with it  ;)

73,  Jack,  W9GT

I like that - -AC mains with no xfmr required, even if you do use one. You have my admiration, according to my 70L7-powered PC speakers (using audio xfmrs in and out).

Is the tall thin gray item under the chassis on the left one of those power resistors encased in stamed metal? Is it the heater dropper? I had a time figuring out how to get rid of the heater resistor heat from inside plastic enclosures.

Here is my 117LGT rig. Tube acts as the rectifier and osc. Cabinet was a special purchase from Federal Cigar‎ Portsmouth, NH after one Nearfest

And the famous W5LET 50C5 rig from PE
Carl
/KPD

And here is the WIDOWMAKER 50C5 for 160M AM

This is a 12BA6 Hartley ECO into a 50C5 final Heising modulated by a 12AX7 into a 50C5. Note the advanced PTO using a piece of gas hose coupler glue and a pencil.

Mike WU2D

Here is my little 6L6 rig originally shown in an article in Electric Radio.  Long Live the 6L6!  6AG7 - 6L6 in RF and pr of 6L6s in the companion Heising modulator.  Puts out about 15 watts AM and a little more on CW.  I changed a couple of things in it since the original article, including adding a tuned circuit to the oscillator/driver stage.  I also had to add a little tag with W9GT over the label on the front, as my call sign then was N9GT.   I've worked many contacts with this rig over the years....still works great.

73,  Jack, W9GT

A couple more shots of the 6L6 rig:
73,  Jack, W9GT

Very nice! I like that! Homebrew rocks!

Here is my version of the 1936 Frank Jones 6A6 pp oscillator transmitter and power supply.  Puts out 5 watts on 40 M CW.  Using 1930s vintage components in xmtr.

73,  Jack, W9GT

More pics of the 6A6 rig:

73,  Jack, W9GT

And more of the 6A6.  Note cloth-covered wiring and line cord.

73,  Jack, W9GT

I was just going to ask where you put the filter caps! Now I see!! Sweet!! :)

Of course....I needed a "little" balanced antenna tuner to use with the 6L6 and 6A6 rigs  ;D

73,  Jack, W9GT

Yes that is a power resistor for the heaters.  Its not metal cased though, just dipped some ceramic material.   I think it is 140 ohms @ 10 watts or so.

Carl and Mike...great little rigs!! :)  George, thank you...you have created some really nice bread board rigs, as well!  Great fun.

73,  Jack, W9GT

Beautiful work Jack! Your antenna tuner certainly will not be the weak link in your chain! 
I am currenly rebuilding my first transmitter which was written up in the September 1964 issue of Electronic Illustrated Magazine.  The transmitter was called the Scrounger since it used parts from junk TV's.  It's a single 6V6 xtal oscillator link coupled to the antenna.  Its built on a cake pan and uses a toliet paper tube as the form for the tank coil and a pilot lamp in place of a plate current meter. 
Yes, "Simplicity is the Elagance of Design".  My next OT project will be a 160 meter breadboard transmitter using a single 203A in the final.  Will probalby modulate it with some 211's either class B or maybe even as a Heising modulator.  The old timers use to use small wooden racks on the desk tops with bakelite front panels. 

I certainly have enjoyed looking at all the pictures and text on this subject. 

Joe, W3GMS     

Thanks for the nice words Joe!  Good luck with the future projects.

Surely not my intent to hijack this thread!!  Pedro, your home brew rig is really nice and your description just reminded many of us how much fun homebrewing those simple little rigs can be.  You did a great job re-using the parts you had on hand to build a useful little rig.

I need to rekindle the fire that I had last winter when I built the 50L6 and 6A6 rigs and complete a little regen receiver from late 30's Radio Handbooks to go along with the xmtr.  Will build it on a matching Poplar board and use period-correct parts.  Also, thinking of brewing-up a little rig using acorn tubes like 954s and 955s to build a mini-AM rig.  Probably only be good for a watt or so, but maybe will have to build a 6L6 leenyar to follow it up  ;D.

Hey, you guys...post more pics of those masterpieces!  Sure enjoy seeing them.

73,  Jack, W9GT

Good looking rigs.  Brings back memories of when there was an "N" in my call sign.

Always looking to improve things, I would ditch the metal 6L6 in favor of a glass one.

I also note that the rectifier tube comes and goes in Pedro's pics.  Looks like sort of solid state plug-in in one of the pics.

As a point of interest, when I built my recent tube exciter, I didn't realize that the 6AG7 was only available in metal until I was committed in the VFO but changed the buffer to a 6CL6.

js

My first homebrew was a single 6146 pie net xtal rig built out of the 1969 handbook, worked great!
I built the cabinet out of circuit board meterial and angle brackets, painted the outside crinkle black which scratched off very easy, used a tv set transformer, and for tx/rx control used buttons out of an old cash register from a fast food place, green was RX and was labled CH BGR, the red TX button was SM COKE!
(they lit up when you pushed them)

I bit of chirp maybe, but I made contacts with that rig...

Brett