The "Linear Power TX" -revisited-

this revisit adds an audio indicator tube as a VU-Meter.

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This information is provided for educational purposes and/or authorized usage only.



Check out the video at the bottom of the page.


Evan's comments on this TX

First: For my comments regarding The "Linear Power TX", which forms the basis for this TX, please see:

Modifications made during this revisit:

  1. I've added a 6E2 as a VU-Meter which responds to the modulated audio.
  2. Note: I had to disassembly the 6E2, tube socket, grind new notches, then spin it to the correct position in the metal frame and reassemble it to get the indictator tube "face" to face the correct direction. You cannot do this with every socket, so you might need to experiment by ordering a couple different types.
  3. Just like my previous "Power TX", I'm using a 6GH8A tube not a 6CQ8 tube. The 6GH8A triode section has a slightly higher amplification factor (46 vs 40) which modulates just a bit better.
  4. The power transformer used is the Hammond 262F6.
  5. Cabinet size is 6" X 8".

Adding a visual VU-Meter adds a pretty cool look!

Final Comments regarding the transmitters found on my website:

Well as you step through my various TX pages you can see the evolution I've gone through to build the best quality, low power, AM, tube type transmitter. I think I've finally..... pretty nearly, achieved it. It's been fun and exciting to research this material and to build a number of different TX's. I've attempted to bring the value of my research to you so you do not have to burn as much time as I have in your attempt to build the same. My advice to you - HAVE FUN - and build you own TX, however do not omit the small stuff, thinking "well this won't make any real difference so I'll leave it out". In the end it all adds up, either for good or bad!


Click on the image below for a larger schematic.


For a closer look at the tuning eye circuit.

The schematic above always show the latest updates. Click on it for a full view.

The pictures below may not show every update.

Click on any image below for a larger picture.

The ribbon cable you see goes to the LED's installed in the tube sockets.

All on a single 6" X 8" top!



To answer your FAQ's


This is what the TX sounds like while listening to a 1938 Air Castle radio - with a 12" speaker.