Low Frequency Waveform Generator LF141, VP142

 Low Frequecy Waveform Generator Type LF.141 and Variable Phase Attachement Type 142.
 Frequency:
0,002 to 2.000 c/s in six ranges with overlap at each end of each range.                    Absolute accuracy +/-3% of setting.
Amplitude:
0 to 20 volts peak to peak (undamaged by short circuits). Accuracy of amplitude  dial +/-6% of  full scale. There are three ranges with full scale 20. 2. and 0.2 volts peak to peak  respectively.
Auxiliary Oscillator.
 Frequency Range:
Approx 0,1 to 1.000 c/s uncalibrated in four ranges with overlop.
Outputs: Square waves of about 10 volts peak to peak at a mean of about -14volts, and triangular  waves of 20 volts peak to peak at a mean of about 0 volts.
Variable Phase Unit.
Output:
Sinewave of the same frequency as the LF.141 and variable in phase 0 to 360.
Voltage:
0 to 10 volts peak covered in one range.
Angle accuracy. +/- 3
Voltage accuracy: +/- 0.5 volts.
Output impedance: 10Ω

Here you find 3 models, 3 with images and 0 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
All listed radios etc. from Servomex Controls Ltd.; Crowborough, Sussex