Ok, so what is it exactly?

[JERSEY 34]

I have never professed to know everything about this collecting lark, but do know that when you think you know it all its best to go back to the beginning and start again. So I need educating and hope one of you guys can help, what is this contraption. I have loads of book on all sorts of German militaria but nowhere can I finf anything on this piece.
Look forward to hearing from someone on it.
all the best,
D.

[Battery Command Post]

Hi

Interesting bit of equipment. From the 'working instructions' and the circuit diagram, I would think its a signal amplifier for a field telephone (for use down a very long phone line). It says that you attach your field telephone set and a cable to the unit, and this amp basically sits in between them amplifying the signal. After set up, you call the 'remote station' and use the Tone Control (Ton I and II) to adjust for distortion (due to overamplification).

I don't know what you'd call it in German.

Rob

[bigmacglenn]

I'm always impressed at the high quality of these German items...appreciate the detailed photos as well!

[Walkwolf]

Rob has nailed it - a field telephone. Relatively common.
Your example is missing the hand-held reciever.........

[Styx]

Ah, nice piece, I saw something similar for sale at a car boot sale once but didn't know what it was so avoided it :/

Robbie

[Drake Pugh]

I was going to say it looked like a raido or a phone. Can anyone do me a favor and look at the forum post 2 down on the vietnam era spooky helmet? THANK YOU

[Battery Command Post]

Rob has nailed it - a field telephone. Relatively common.
Your example is missing the hand-held reciever.........

Sorry Walkwolf, that's not what I said. It's definitely not a regular Wehrmacht field telephone. What it seems to be, literally, is a tetrode amplifier (using an RV2,4T3 tetrode valve). Whereas you would normally attach the phone line to a field telephone, what you do here is attach the phone line to this unit (1 on circuit diag), and then attach a field telephone to it as well (2).

Looking at the circuit diagram, when this unit is switched off, the setup will operate as a normal field telephone, as the on-off switch (U1) will connect the line to the phone directly in the off position. When it is switched on, the amplifier unit is connected to the phone line directly and powered up, amplifying the signal from the other end of the phone line.

I would have to know exactly what plugs into it to figure out what else it does. It has sockets for "kopfhorer" (headset) and "taste" (button or key?), but not sure what form these would take.

It's a field phone accessory, which i imagine would be used over a very long or poor quality line, to boost the signal. The British Army had a very similar unit, the Telephone Set F High Power, which was an amplifier and field phone all in one unit, used for the same situation.

Rob

[Walkwolf]

My bad, Rob - I did not read into your post enough to get the jist of everything
you were saying - I understand now, and can appreciate it's importance
as a signal amplifier.

[Battery Command Post]

My bad, Rob - I did not read into your post enough to get the jist of everything
you were saying - I understand now, and can appreciate it's importance
as a signal amplifier.

No problem, just thought maybe i didn't express my thoughts clearly enough

I have to state though, an amplifier is what it seems to be, as it has some unusual features in its circuit design (e.g. it has a strange output signal feedback arrangement to one of the grids, almost like an ultralinear amp), and some of the circuit symbols are not what I'm used to with British style diagrams of the period.

If it were mine, I would get some battery holders, batteries, some wire, banana plugs, solder and rig it up to get it working to see how it operates. Shouldn't be too hard as long as the valve/tube is OK (and they're a lot tougher than people imagine).

Rob