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Author Topic: Single power transistor crystal controlled CW rig info  (Read 1117 times)

Offline ve3lyx

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Single power transistor crystal controlled CW rig info
« on: November 08, 2015, 03:59:59 UTC »
Back in the corner of my mind I remember a single power transistor rig in a magazine crystal controlled and putting out about 4 or 5 watts. I took a quick try at getting a C2029 transistor to run as a crystal osc but it doesn't want to go. Harry Lythal designed one that used a LM317 voltage regulator instead of a common transistor so it should be possible with the real deal.  Anyone have any ideas or experience with this type of QRP transmitter?
don VE3LYX

Offline VE4AKI

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Re: Single power transistor crystal controlled CW rig info
« Reply #1 on: November 10, 2015, 19:36:25 UTC »
Hi Don. I had a look through my collection of QRP articles and plans which go back a few decades. I found some info on one transistor transmitters but none that put out as much power as you mentioned. The closest one is called the cubic incher for 40M or 20M but puts out about 2 watts at 12V. Most one transistor xmitters put out about one watt or so. I have built a few by paralleling two or four transistors to gain a bit more power. I have also built xmitters using a 24v. supply which will gain a bit more power as well. I'll keep my eyes open and let you know if I run into anything. Hope that helps.
---73   Tom  VE4AKI

Offline ve3lyx

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Re: Single power transistor crystal controlled CW rig info
« Reply #2 on: November 11, 2015, 03:27:48 UTC »
Ah AHA . The cubic incher. That is the one I was looking for I knew it was cube something.
Yes I have built a little lattice before and soldered four 2n2905s to it then pushed it in the transistor socket I was using. I built the micronaut recently first with a single 2905 then soldered another directly underneath by pulling its base lead between its legs . It actually works quite well. I had thought the cubic incher was more power but I was only going from ancient memory. Still it might offer something. Where was it found? Thanks for you efforts.
don VE3LYX
I found the schematic Tom, Thanks again.

Offline VE4AKI

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Re: Single power transistor crystal controlled CW rig info
« Reply #3 on: November 11, 2015, 16:37:47 UTC »
Hi Don. Glad you found the schematics. I have photocopies of the articles from QST? if you are interested, I could scan them and get them to you.
73------Tom

Offline ve3lyx

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Re: Single power transistor crystal controlled CW rig info
« Reply #4 on: November 12, 2015, 03:25:46 UTC »
I found it all. Even the new improved version. Now I remembered why I didnt build it. Toriods. Dont have any of the good stuff. I also now have the micronaut up in power using a piggybacked pair of 2n2905s. I am probably close to that power right now. Set it al up in the upstairs shack on 3560khz and listening on a good regen. So if any hear me, go ahead and make my day.
don Ve3LYX