Date of Design The dates of design shown below in the table start in 1928 and finish in 1934, so the overall set can be considered as a 1934 transmitter.
Frequency Range
Transmitter 3GB L/F 3GB H/F Spark Transmitter 6D
Frequency range 77-500kc/s 3000-20000kc/s 77-500kc/s 77-500kc/s
Power supply 20kW Alternator 20kW Alternator 20kW Alternator 20V Battery
Filament supply 3kW Alternator 3kW Alternator  - -
Valves used 6 5 - -
Wave form CW & ICW CW & ICW Spark Spark
Associated wavemeter G56 G56 G56 G56
Approximate range in miles 1000 World wide at times 150 50
Date of design 1934 1934 1934 1928
Power to Final Stage 8-10kW 3kW 1.5kW 40 Watts
Power Supply  See above to Frequency Range. This was the most powerful transmitter in the Fleet and was a modernised version of the Type 36S.

The power supply control panel was large and was split into four separate boards as shown in this picture.  The boards were fitted opposite the Transmitter panels within easy reach of the operators in the CRR [central receiving room]. 
The 20kW Power Supply Panel with the 3kW Filament Supply + 20v DC Battery for the Emergency Spark Set

Type of Set See above to Frequency Range.
Wave Form See above to Frequency Range.
Method of Producing Oscillations  Self
Where used/fitted.

The Type 36M is the main transmitter in heavy ships and all modern [1934] cruisers and is a much modified Type 36S.

The chief alterations embodied in the new set are:-
a.  Improved H/F performance
b.  Greater frequency stability
c.  Arrangements for grid signalling, thus enabling the set to be used for automatic high speed transmissions if required
d.  Removal of the lower power attachment and the provision of means whereby the L/F transmitter can be used at a low voltage to meet low power transmission requirements
e.  Inclusion of a spark transmitter for use in case of emergency
f.  Automatic control of the output voltage from the filament alternators by means of reversing boosters
g.  Removal of the aerial tuning linkboard
h.  Some of the Type 36S power boards have been modified for use with the 36M.

The main controlling panel, the Type 2G, containing all the necessary switches to control the set is sited in the CRR next to the operators position. All "on" "off" pushes for the auto-starts are fitted in the CRR as are the main alternator regulators, AC voltmeter and aerial ammeter.

Associated Wavemeter See above to Frequency Range.
Small Schematic

CLICK this file to see the full schematic 36M FULL SCHEMATIC.pdf

CLICK this file to see the Grid Signalling and Absorber Circuit System GRID SIGNALLING.pdf

20V Warning Circuits protects the Receivers in outlaying wireless offices when transmitting on the main set/aerial [see the Type 36S for more detail].

The main keying circuits.


Above and below are both parts of the Type 36M



36M Part of the 20kW Outfit

Part of the 20kW Power Outfit

Grid Signalling and Absorber Circuits Unit