[GreenKeys] Military Dovetron in the rack with my RTTY repeater operates a polar relay

[Tom Hunter]

There is nothing mysterious about it. The military Dovetron only has polar
outputs and I needed to key a neutral loop.
I grabbed the first polar relay my hand landed on, adjusted it by the
instructions in "The New RTTY Handbook", tried it on the +- 12 volt output
of the Dovetron and it worked.

I cut and filed a rectangular hole in the cover of a 4X4 inch electrical
box and bolted the relay to it .I pulled wrap-around pins put of a broken
octal tube socket, squeezed them a little tighter and used them to make my
connections to the pins on the polar relay.

The Dovetron is connected to the external speaker jack on the Icom repeater
receiver.  (The controller is connected to the DB-9 on the Icom adapter
cable.)

The biggest problem is that the Dovetron Mark and Space settings drift. In
my unheated radio building, they drift horribly. Even the one in the house
drifts.

I have a dual function generator set for 2125 and 2295 sine waves in my
den. I send the outputs to my radio building also. That makes it very easy
to reset the tones on my Dovetrons.

This is the generator I bought: eBay item number: 112440163822

TIP: Once you have it set up, store your settings in memory 0 (zero). On
power-up, it boots from memory 0.



Tom   N3CRK
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