German radio control box

One of our unknown items here at the Freeman Army Airfield Museum in Seymour, IN USA is the box in the accompanying photo. We think it has to do with controlling the radios (or radio accessories) in WWII German warplanes. This may have come out of a Ju-88, but the same radio equipment was used in many different airplanes. I would like to know what the box really controlled, from a practical standpoint. I need to make a sign, explaining the part for museum visitors. Any help will be greatly appreciated. Note that I put the chrome ballpoint pen in the photo to give some idea of the scale; size of the box. Thanks for your help.

Being a front. There must be a fl-number.

It from a radio set ofcourse but wich one.

Controls of radio wire that was put out of the plane?

Snautzer01 said:

Being a front. There must be a fl-number.

It from a radio set ofcourse but wich one.

Controls of radio wire that was put out of the plane?

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The box is at the museum, and I am at home. I plan to go to the museum tomorrow anyway. I will get the box and bring it home, and look it over for any numbers or other markings.

Umformer is converter, Empfange is receive and Heizung is heating....

This is the Selbstschalterkasten ( auto-switch power on/off and overload protection box. In other words the box for the electric circuit breakers ) used with the FuG 10 radio set and other ones also for the Ju-88. It is a box for four circuit breakers and the one is still in the box. The inscriprions there depict the electrical circuits these protect.








the source:
FuG 10 installation

Excellent!

Wurger said:

This is the Selbstschalterkasten ( auto-switch power on/off and overload protection box. In other words the box for the electric circuit breakers ) used with the FuG 10 radio set also for the Ju-88. It is a box for four circuit breakers and the one is still in the box. The inscriprions there depict the electrical circuits these protect.

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the source:
FuG 10 installation

Junkers Ju88 ‑ FuG.X. ≈ Příručka pro palubního radistu a osádku – ZELENÁ VLNA

zelenavlna.com

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Thank you Wurger. You have solved my problem. Now I know what it is, and what it does. I do have one remaining question: Can you tell me what the right-most inscription says, and what it means in English? I believe the bottom line reads Umf.U8, but the top line is obliterated on my box. I can read only one letter in the top line; it is an "e".

Larrythepilot said:

The box is at the museum, and I am at home. I plan to go to the museum tomorrow anyway. I will get the box and bring it home, and look it over for any numbers or other markings.

Click to expand...

Snautzer01:
You are correct; there is an FL number. I brought the box home, examined it under good light, and saw numbers under corrosion. Using a brass "toothbrush", I removed the loose corrosion, and more numbers were revealed. Using a magnifying glass, I believe the numbers are FL 32404-8. I'm not sure about the dash between the 4 and the 8; the metal is completely missing there (small hole), but the spacing and surroundings suggest a dash. But now that Wurger has told me what the box is, and what it does, I don't think you need to work on it anymore. Thank you for your help.

Larrythepilot said:

Snautzer01:
You are correct; there is an FL number. I brought the box home, examined it under good light, and saw numbers under corrosion. Using a brass "toothbrush", I removed the loose corrosion, and more numbers were revealed. Using a magnifying glass, I believe the numbers are FL 32404-8. I'm not sure about the dash between the 4 and the 8; the metal is completely missing there (small hole), but the spacing and surroundings suggest a dash. But now that Wurger has told me what the box is, and what it does, I don't think you need to work on it anymore. Thank you for your help.

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Yes we have a Wurger. As always did a terrific job. Thanks for showing this piece.

Larrythepilot said:

Thank you Wurger. You have solved my problem. Now I know what it is, and what it does. I do have one remaining question: Can you tell me what the right-most inscription says, and what it means in English? I believe the bottom line reads Umf.U8, but the top line is obliterated on my box. I can read only one letter in the top line; it is an "e".

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The Fl. 32404-8 is correct and, as I mentioned above , means the "Abschirmgehäuse für Schutzschalter" = the shielded box for circuit breakers. The box was making by the Siemens, Berlin in 40'.


the source: the net.

The inscriptions :

- Sender Umformer - Transmitter converter
- Empfänger Umformer - Receiver converter
- Röhren Heizung - Tube heater
- Anoden Umf. U.8 - Anodes of the Voltage converter U.8

* Umf. U8 = "Umformer U.8" made by the Lorenz/Telefunken, Berlin. This is a power supply dynamotor (rotary generator)/ anode voltage stabilizer with the current regulator for the blind landing receivers EBl 1, EBl 2 and EBl 3 of of the radio landing reception system FuBl 1, FuBl 2 or the PeilG radio direction finder systems rather than for the FuG 10 radio set. Because all the navigation systems were combined with the FuG 10, the cicrcut breaker box could keep the one there.
There were used other dynamotor/ voltage converters for the FuG 10 radios, the Umformer U.10/S or Umformer U.10/E what can be found in most of the Ju-88 pics with the radio set. These two were of a slightly different, from the U.8, architecture. The U.10 devices can be found at the bottom of the Ju-88 radio wall usually.

The Umformer U.10/S on left and the U.10/E one on right ...



The Unformer U.10/S ...



the pic source: the net.

The Umformer U.10/E ...


the pic source: the net.

The Umformer U.8 ...


the pic source: the net.

I hope this helped.