TRANSMITTERS & TRANSCEIVERS

Type 9 Transmitter

DATE OF DESIGN

1913

FREQUENCY RANGE

1.8 Mc/s to 2.5 Mc/s but frequencies used are 2.384 Mc/s and 1.915 Mc/s

POWER SUPPLIES

Motor Alternator the output being 1.25kW, 100v ac, 250 cycles and 2500 revs.

RANGE IN MILES

TYPE OF SET

SPARK

WAVEFORM

METHOD OF PRODUCING OSCILLATIONS

WHERE USED/FITTED

Type 9 is a low powered spark transmitter/receivr which was fitted into Cruisers and also in some Battlecruisers as the Auxiliary set for short distance communications when in company.
Approximate distances achieved up to 25 miles. As the text in the Pre ""1 files show these sets (Type 3 in a Battleship) were the original "short distance set" and were used as we use VHF/UHF between ships operating in close proximity of one another. Clearly they were using the ground wave of a short wave transmission oblivious of where or what the associated skywave was doing! Read the PDF file under Further Reading which is a basic description of the Type 9. Many of the expressions used in the text of the PDF file have been covered and explained in the Pre WW1 files. DP means -difference in potential- (we say PD) - potential difference - today. Note under 'interference' the problems they had between the main wireless office (medium to high power transmissions) and the auxiliary wireless office (low power transmissions) especially when each separate aerial was quite large much more so than the aerials of today.

ASSOCIATED WAVEMETER

G9

FURTHER READING

Type 9 Description.

HMS ALBERMARLE Trials with Service MK II and various articles on Installation, Spark gaps, keys etc Look at Type 3

IMAGES, PHOTOS, DOCUMENTS, SCHEMATICS ETC.

Type 9 Photographs, Schematics, Documents

NOTES.