EXC2501 Monitoring Receiver

Technical data

No information is available but according to a friend of mine, it might be a prototype of spy bug receiver unit built into a suitcase.
It may have been designed by the 785th CGE. The identification tag indicates 1983 and the reference R2. Is it 'reference of receiver 2' or 'receiver number 2'?
It was made by Chatain & Blanchon, a company known to manufacture and supply equipment to intelligence services and other government entities.

Inside, we can still see the folding marks made with a pencil on the brass shielding boxes.
The suitcase is very heavy. It integrates a power supply and a battery charger.
I have no diagram and I will probably never find them.
It was not working but with a little logic and analysis, it was possible for me to repair the unit and make it work.
I finally found two HS components: a 4543B (BCD to 7-segment latch / decoder / driver) driving one of the frequency digits and a 4013 (bistable) in the data multiplexing circuit.

Pictures

EXC2501 Equipmement
EXC2501 Suitcase


EXC2501 Electronic


EXC2501 Detail


EXC2501 Logic cards

EXC2501 repair

Unit working on HF band - AM demodulation

Last revision: 2019/03/25