Signal Generator for Fusprech.d & f
The Fprüf.i was a single-frequency signal generator that was used to calibrate the local oscillator of the Fusprech.d & f; 18 - 24 MHz. This signal generator employed a quarz 1,500 kHz.crystal to generate the necessary test frequency. The Fprüf.i was powered from the same source as the receiver and used a special power connector shown below.
Data plate, and headphone terminal.



Top of the unit.



Lid for servicing the vacuum tube and tuning the output frequency.



Power connector.



Power connector with strange English writing on the Bakelite.



Bottom of the unit.



Antenna connection terminal.



Cover off.



Cover off.



American capacitor in the middle of the photo. The measurement terminal can be seen at bottom-right of the photo.