[ARC5] Prototype transmit-receive control logic (a photo)

[Leslie Smith]

G-day all:
This photo shows a general view of a card designed to switch aerial and
power between a generic receiver and transmitter.
It has the same general function of a BC-451 and BC-422 card.

I haven't seen a circuit with this general function before.
The card is a prototype and has several problems.  (Example:  I included
a keyed side-tone oscillator, but it takes so long to "start" that it's
useless.  The oscillator must run continually and I must add a keyed
buffer.  Also  the antenna bridge works just fine for a 50 ohm aerial,
but not of a 5 or 10 ohm "command" transmitter aerial.

   73 de Les
   vk2bcu at operamail.com
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