German FUG 10 airforce radio installation
FUG 10 means: Funk Gerät 10.
The Fug 10 is a very complex installation for communication between airoplane to airoplane (Bord zu Bord) and from airoplane to ground (Bord zu Boden). It consists of several receivers and transmitters for the shortwave and long wave and a lot of remote controlls. In other circumstances it is combined with navigation purposes. (Peil G6 with EZ6 receiver, then called Fug 10 P).
The transmitters are very stable in frequency, by using special temperature compensating arangements in the oscillator circuit. Consider, that this oscillator is not crystal controlled. The heat inside the cabinet is very high, because the principle is a MOPA transmitter in a very small cabinet. The oscillator valve is RL12P35, which much deliver much driving power to the power amplifier. This power amplifier has to deliver about 60 watts to the antenna at CW mode, by use of 2 RL12P35’s.
This arrangement was not only the use of ceramic material, but also a special condenser block in the circuit of the oscillator. These condensers had a big dielectric loss with a particular temperature coefficient. More about this a extended explanation n the post EZ6 DIRECTION FINDER.
Displayed in the picture above my Fug 10 equipment. It is in working condion! I use the the short wave transmitter and receiver in the 80 meters amateur band and made several contacts. The frequence stability is amazing!
Most units (EK,EL,SK FBG3, SchK13 and U10E ) are in working condition. Upper row “Funkerschaltkasten (switchbox), EK receiver (shortwave 3-6 Mc), EL receiver (long wave 300-600 Kc). Mid row “Fernbediengerat” FBG3 (tuning the antenne tuners, switching antennes etc.), SK (shortwave transmitter), SL (longwave transmitter). Lower row “Eigenverstandigung Verstarker” RG 10 (intercom amplifier etc.) , “Umformer” U10 e (rotating power transformer for the receivers).At the back of the rack are placed, not visible on the picture, the AAG2 antenna tuner and the transmitter rotary transformer U10S.
Picture above: an older picture, close-up of the units.
On the left lower row, a important control unit, the FBG 3, explained later in the post. At the front 2 knobs for tuning the AAG for matching the antenna to the transmitters for long wave and short wave. One knob for long wave (blue) and the other for short wave (red) . This knob is mechanical attached to a synchro motor system. In the mid the antenna current meter. With the big switch, with scale, in the mid, you can switch the transmitters either for long wave are short wave and which antenna to be chosen. Normally one short antenna f
or short wave, and a long antenna, the trailing antenna, for longwave. It is possible to change the long wave transmitter from trailing antenna to short antenna, so the short wave transmitter from the short one to the long one. This in case, one of the antennas is broken.
In the above picture you can see at the left de ADb ‘s (Anschluss Dose ). In this case a ADb13 type. It is a remote connectionbox for the microphone-telephones in the oxygencaps of the crew. At the right the U-10-e rotarytransformer for the receivers.
On this picture above, you can see the trailing antenne type AH-10. At the front of the “Funker Schalt Kasten” is a switch to move the antenna wire up or down. Also a indication meter is placed, for how far the trailing antenna is released.
The FUG 10 with the fully working AAG 3. Note that the trailing antenna is also there, which came later in the collection.
The AAG on the testbank. Just to be seen, the schematic diagram and wire connections.
The inside of the AAG. Left the vacuum relay. When pushing down the CW key, the relay comes up. When releasing, it falls down again after a few seconds. This is working very well and pleasant. Above the long wave variometer. Above the variometer, the indication scale of the tuned frequency, the same scale is on the FBG3 control. Both he scales are turning synchron with tuning.
Another view of the AAG. At the left, the short wave variometer to be seen. Just in the mid, the synchro -motor for driving the variometer coils. This motor is driving by a “Drehfeld System” , a kind of electrical achs, coming from a same type of synchro in the FBG3. This synchro is turned by hand with a knob, with same scale as on the AAG, to tune the match.
A nice look to the vacum antenna relay. It can be activated (transmit and receive) by 2 coils, seen on the picture.