DATE OF DESIGN

1. TX 3K L/F - 1924.
2. TX 3K H/F - 1930.
3. TX 4H (with Attachment) - 1925 (attachment 1930).
4. TX 6F - 1930.

FREQUENCY RANGE

1. TX 3K L/F - 100 to 670 kc/s an 800 to 1365 kc/s.
2. TX 3K H/F - 5770 to 26000 kc/s.
3. TX 4H - 375 to 1765 kc/s.
4. TX 6F - 100 to 900 kc/s.

POWER SUPPLIES

1. TX 3K L/F - 3kW Motor Alternator. Filament supply - 1.25 kW Alternator
2. TX 3K H/F - 3kW Motor Alternator. Filament supply - 1.25 kW Alternator.
3. TX 4H - ships mains or 6V battery.
4. TX 6F - 3kW Motor Alternator.

RANGE IN MILES

1. TX 3K L/F - 800.
2. TX 3K H/F - World Wide at times.
3. TX 4H - 10.
4. TX 6F - 100.

TYPE OF SET (VALVES USED)

1. TX 3K L/F - 3.
2. TX 3K H/F - 3.
3. TX 4H -2.
4. TX 6F - .

WAVEFORM

1. TX 3K L/F - CW an ICW.
2. TX 3K H/F - ICW.
3. TX 4H - ICW.
4. TX 6F - SPARK.

METHOD OF PRODUCING OSCILLATIONS

SELF

WHERE USED/FITTED

Type 37S is a medium power valve set arranged on many panels. In some cases, where H/F Panel 3KS has not been fitted, but the set has been modified to receive this panel, it is known as a TYPE 37A. Where no modification has been made, the set is known as a TYPE 37 and the panel, a Type 3K. TYPES 37, 37A and 37S are fitted in the Main W/T Offices of DESTROYERS and SLOOPS and in Second W/T Offices of modern classes of BATTLESHIPS and CRUISERS (1930's).

ASSOCIATED WAVEMETER

1. TX 3K L/F - 1492B or G9.
2. TX 3K H/F - G13 or G8 and G7.
3. TX 4H - 1492B or G9.
4. TX 6F - 1492B or G9.

FURTHER READING

How the aerial circuit worked with one or two operators.

IMAGES, PHOTOS, DOCUMENTS, SCHEMATICS ETC.
(Click images to enlarge)

Type 37S Photos and Schematics.

NOTES.

The Type 37S was widely fitted throughout the Fleets. It comprised of four parts, with three parts being VALVES and the other SPARK. The dates of design started in 1924 and finished in 1930 so the overall set can be considered as a 1930 transmitter.

Photo 1 - 3K Rectifier panel Upper and Lower.
Photo 2 - DC Auxiliary Circuits schematic.
Photo 3 - 3K H/F Transmitter schematic.
Photo 4 - Transmitter 3K H/F schematic.
Photo 5 - Type 37S Transmitter 4H Schematic.
Photo 6 - Transmitter 3K H/F - 3KS panel.
Photo 7 - Transmitter 4H.
Photo 8 - Transmitter 4H.
Photo 9 - 37S Transmitter.
Photo 10 - 37S Transmitter.