Please help!, What is it designed to do?


Joined Jan 27, 2019
Welcome to AAC.

Without seeing the front it is my surmise we are looking at the back of a residential intercom main station, the technology itself is quite old, maybe 70s vintage but that doesn’t mean it wasn’t manufactured more recently.

Why is it a mystery? What does the front look like?


Joined Sep 17, 2013
+1 Welcome to AAC!
Judging by this thread (in German) which a Google search of the screen-printed data produced, it looks like the audio board from an old CRT TV. The elliptical speaker is typical for such a TV.


Joined Sep 24, 2015
As for how old it is - I don't see any date codes on the PCB that I recognize. However, there's a number on the board, "37476", which when put into an Excel spread sheet and then changed to a date format comes back with 08/08/2002. That's just a guess and perhaps a coincidence, but it does look like it could be 20 years old. Could be newer and someone using older technology. Post a picture of the front side.

My first thought was part of an alarm system, but I think Yaakov has a better take on what it may be. But without seeing the front side of the panel we're just going to be guessing.

I DID notice this battery, which is why I'm thinking possibly something that would need backup power such as an alarm system. Upon closer examination the battery is a Ni-Cd, or Ni-Cad, or Nickel Cadmium. That's harkening back to older days, and there's a good possibility the battery is bad. I have a couple NiCad's (DeWalt 18V tools). Recently one of those batteries stopped maintaining a charge. Upon opening it up I found 7 out of 15 cells that went bad. After charging them, within a week they had fallen to essentially zero volts.
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Joined Jun 22, 2012
It's got a jack socket , a xtal decoder of some type, battery backup, speaker , looks like a power amplifier heatsink,
hard to say what it is.


Joined Jan 23, 2018
It aso has a tuneable transformer, and at least one more circuit board that we only see the solder side of. I see an IC and that should have a part number and a date code. But without seeing more details, such as the other side, I will not offer even a guess. Given the appearance that the PCB we see has been broken off on the one edge, it is a prime candidate for a save parts effort. And a 7 watt 25 ohm speaker is strange.


Joined Jan 27, 2019


Joined Jan 23, 2018
Apparently my surmise was correct.
And once again, that is what the thing USED TO BE! With the very broken circuit board it is not likely that that any of those functions can be realized now.. But possiby the amplifier output section might be recoverable. And certainly the heatsink is OK.


Joined Jan 29, 2010
hi Bill.
The TS's 'one and only' post asked this question:
Can anyone tell me what this is??? What is it designed to do? And how new is it perhaps?

What relevance has your last post got to do with the question asked.???



Joined Aug 1, 2013
It might be an intercom master station, but it is not the one in post #7. The buttons are in the wrong place.

The speaker values make sense to me, because domestic intercoms are just plain weird.

The tan pc board has had a rough life. A small portion in the RF area to the left of the heatsink has been broken off, and a much larger area to the right of the speaker is missing. In both cases, it looks like a violent, uncontrolled separation. Whatever this thing was, it cannot be restored to operation.