[GreenKeys] Tempest Dovetron

[Duncan M. Brown]

I was checking out a Tempest Dovetron that had no output from the EIA or
MIL connectors for a friend.

Found a manual on line and after some troubleshooting, found a pinched wire
shorting out the data signal coming off the bit processor board, and I get
output now (but haven't checked out all the features.).  It seems like a 
very good converter, but after playing with it for a while I had some
questions that maybe someone with more experience with this unit can answer:

  1) First thing I noticed was a burnt resistor smell when I opened it up. 
I found a burnt resistor (but still good - 200 ohms) soldered across Q8,
the 7815 voltage regulator (from 20v-in pin to 15v-out pin). Is this
normal?? or a "standard" fix for something????

  2) With no audio input signal, both of the "Loop" LEDs are always on.  Is
this normal??    The "Loop" LED never goes off, it just flickers during
reception of a TTY signal.

  3) On the right side of the panel, there is a "Clear/SDS/Off" switch.  No
mention of it in the manual.  What does it do??

  4) Will have to make some sort of level shifter to drive a printer (I
have found various ones in the Green Keys archives), but I was wondering if
any one knows what TTY equipment the military used with this Dovetron ( Or
was it just used with a "dumb" video terminal??)

  5) The AN/UGC-74 has a switch for "low level" - will it work with the
Tempest Dovetron EIA or MIL outputs??

Thanks & 73,

Duncan, K2OEQ
http://www.antiquewireless.org/