Hi,

I decided to open up this military transceiver which a tenant
left about a decade ago -- during the non-pc days of s. africa.

It looks as if it was for a tank or armoured car. Made by Barlows.
2 units SO/53 and VS/57 which strap into a base unit: the
power distributor B57.

It's 30 - 40 Hz steppable.

Q1. Is this one of the military frequencies ?

The SO/53 unit has 7 internal cans: Tx, VCO, TLT, Audio, IF, I.C.,Front End.

Q2. what are TLT and I.C. ?

After carefully tracing/testing the power (24 VDC), I obviously want to
monitor the audio out, which I'm guessing is to earphones; but I can't
find any obvious connector.

There are 2 connectors: 8-pin on the SO/53 unit and a similar one on
the base-power-distrubutor unit. They have 'dust covers'.

Q3. Is this possibly the earphone/mic I/O ?
Why would there be 2 on the SO/53 unit and one the base-unit ?
Perhaps to allow 2 or 3 persons to listen ?

Q4. Is there a standard military configuration, or must I just measure
between the 8 pins to find out which is the audio-out ?

The SO/53 unit has a coax/bnc to the VS/57 unit marked 'anten'
and next to it [and confirmewd from inside going to the same RF LC
group] what-looks-like a female thread for a whip-antenea, which
is 5.7 ohm to chassis. Since the thread is horizontal, someone suggested
that the unit could be unclipped and worn vertically on the belt;
except how the power-source-springs would be replaced is not clear.

Q5. How else could a whip operate when the female thread is
horizontal ? OK perhaps the 'dials face upwards' !?
-----------

The lower VS/57 unit seems to be the RF power unit, with some 1 watt
resistors and 'flat rf transistors': TWR pt9783 & vmp4 7848
and some TTL which together with 2 leds which change from green to
red, indicate various diagnostic states.

Q6. How could I proceed to test this thing ?
I've got 1970 - 1980 telecoms experience but not really RF.

Thanks for any advice possibly email also to:

easlab AT absamail . co . za

== Chris Glur.