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Home-built 70cm ATV transmitter
  Homebrewing can be fun!

Back in the 80's, I successfully built an ATV transmitter that operated on 426.25 & 444.25MHz.
 
 
  Let's peek inside.

Here you can see three of the five boards used. Separate line audio and video come in from the back of the unit. Desk mic connection is from the front. On the far left is the "sync stretcher" pcb; the 5.5MHz audio modulator near the front and the exciter/tripler pcb towards the rear.
(The 444.25MHz exciter has been removed.)
 
 
  The rear panel.

On the back panel is a 3 stage PA which has the final transistor modulated via an rf transistor with the video. Output is about 5 to 7 watts modulated. Double sided pcb makes good rf shields and is easy to solder feed-thru' caps to, too!
 
 
  Another view.

Here, again, with a bit of a side view. This shows a piece of veroboard which has a transistor flip-flop to operate the flashing tx led on the front. It was simple and worked, so it was stuck in place with double sided tape!
 
       
    2006-2009 S.Spirat 
Another SPIRAT initiative