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Sensibly equivalent to:
CV29 CV1580 E960T VT98
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The CV1098, also known pre-CV as the VT98, power triode is pre-WWII vintage. The valve is the thoriated filament version of the 1936 VT58 (later named CV1058) pulse triode. The design was used in the UK Chain Home Low Radar that operated between 20 and 55 MHz. The original tungsten filament VT58 was developed from the M-OV ACT10 forced air cooled triode and that itself was a development of the CAT15 cooled anode triode.
The filament is a bright wire helix connected to the two base pins by stout rod supports. The grid is brought out to the side contact and stands on wire supports and encloses the filament. The anode is a copper bell with external brass collar.
The CV1098 has an anode dissipation of 750 Watts and can operate at up to 100 MHz at full rating and 250 MHz with reduced rating.
The cooling collar is 85 mm in diameter and has holes drilled through it to form air tubes.
The GL2 transmitter used a pair of squegging VT98's as oscillator driving another pair of VT98's in push-pull as PA. This arrangement generated 10 kW pulses 1,500 times a second to a highly directional antenna, and it was this gun-laying radar that was probably used in the battle of El Alamein.
See also CV1098 in original polythene bag.
The wide glass tube envelope is 60 mm in diameter and, excluding the base pins, is 308 mm tall.
References: Data-sheet & R J Sutherland.


Absolute Maximum Operating Conditions
Thanks to Frank Philipse for supplying the above PDF datasheet.
Updated April 03, 2019.
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