Original Item: Only One available. This is a very rare German 1942 dated military field telephone 10 line switch board. It bears the original data plate that reads:

7019    1943

This plate is the serial number and year. There is a manufacturer’s stamp but we do not recognize it, AB inside of a 3D square.

It appears complete with all internals, connections and wires, the interior bears an ink waffenamt. We are not sure if its functional and have not tested it, but do not see any obvious reason as to why it would not work!

Comes ready to research and display!

Kleiner Klappenschrank zu 10 Leitungen 10 line switchboard

The redesign of equipment in 1933 had the aim to simplify and the new 10 line field switchboard would be as simple as possible, omitting buzzers, alarm bells, built-in telephone and provisions to connect to public networks. These functions would have to be taken up by external accessories where necessary. At the same time the unit was redesigned for “single interconnection cord” operation, negating the need for separate interconnection cable indicator flaps. Instead of eight cables, the unit now has 10 interconnection cables, one for each line. The basic design with a falling indicator flap, interconnection button and interconnection cable socket for each of the ten lines remained unchanged.

To operate the new “Kleiner Klappenschrank zu 10 Leitungen”, an external FF 33 field telephone would have to be connected. If connections to public networks were required, an “Amtszusatz” or public network connection unit would be required. The redesign resulted in a unit roughly half the size and weight of the old OB 17 model. The unit did not require any presetting of jumpers or interconnections, making it far simpler to operate. A metal lid protecting the top and the use of the standard FF 33 carrying strap allowed the switchboard to be carried in the field and protected it from the weather.

Two locks on the side allow the unit to be opened, giving access to the interconnection cable storage compartment. Also in this compartment is a 30 pole plug socket, which can connect the switchboard to a remote line terminal unit, negating the need to connect the lines directly to the switchboard.

Normally the incoming telephone lines are connected to the terminals on the top panel. Apart from line connections, the top panel has two terminals to connect a FF 33 field telephone and three terminals to connect an external alarm battery and alarm bell. These are all the connections that the operator had to deal with.

When an incoming call is received the signal flap of the relevant line will drop, revealing the number of the line behind the flap. Press the connection button for the relevant line and speak to the caller via the handset of the FF 33 field telephone (remembering to depress the microphone switch in the handset while talking). When the caller has indicated which line he wants to speak to, press the connection button for that line and turn the generator handle of the field telephone. When the call is answered, place the interconnection cord of the caller into the interconnection plug socket of the outgoing line. Return the signal flap of the caller in the up position and press the red connection release button on top. The call is now connected.

At the end of the call, one of the callers will turn the generator rank, resulting in the signal flap of the incoming line to drop. The operator can now remove the interconnection cord of that line and replace it in its storage socket. Close the signal flap to reset the switchboard for the next call. Conference calls can be made by repeating the connection process: the interconnection cable of caller 1 is plugged into the interconnection plug socket of caller 2; the interconnection cable of caller 2 is plugged into the socket of caller 3 etc. In theory, all ten lines can be connected to a single conference.