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smmini.jpg (1083 bytes)smallmerc.jpg (1433 bytes)Vintage Valves

Info on replica early valves

rvalve.jpg (6150 bytes)dev.jpg (6515 bytes)
< 'R' valve (1922) The first type of triode which was widely used. Thin wire filament is suspended inside helical wire grid, inside tubular anode.

> Marconi DEV triode (1924). designed for low capacitance  to improve high-frequency performance in short-wave radio applications

triple.jpg (12477 bytes)fp610.jpg (7063 bytes)

< Ediswan AR (1922), Cossor P2 (1922). Cosmos SP18 (1925). The Cossor device used an unusual 'hat' construction to avoid infringing patents which specified tubular electrodes. This construction can also be seen in the Cossor 610FP, right. Cossor 610FP data

radtron.jpg (6578 bytes)det.jpg (12026 bytes)< Radiotron UV202 transmitting valve (1921). Marked ' Licensed for Amateur or Experimental Use Only'

> GEC DET18 and Eimac 35T, very similar construction despite being made on opposite sides of the Atlantic. I've found no reference to either of these in any of my books.

This info from  Manuel Carbonell : 35T: Equivalent to 3-50A4.. High mu triode, oscilator, class-B modulator or low frequency amplifier, class-C buffer, doubler or amplifier.
Plate power: 35 W (max). Plate voltage: 1500 V (max).  Maximum frecuency: 100 MHz.

From Ron Pond : The DET18 was used as a class C unmodulated amplifier ( Telegraphy)
Filament Voltage; 5.0@ 4A
Anode Voltage; 1000 @ 100Ma
gm. ; ( uA/V ) 2550
Max Freq; 100MHz

dl14.jpg (9482 bytes)pent.jpg (6258 bytes)tetr.jpg (8418 bytes)< DeForest 'Audion' DL14 Low Mu Amplifier (1927).

> Tetrode with side terminal, Philco 43 Pentode (1931)

diag.jpg (13182 bytes)vt121.jpg (5958 bytes)< Two valves with angled electrode assemblies, left one unmarked, right STC 'Micromesh' R3   indirectly heated full-wave rectifier (1932).

> VT121 triode, possibly designed for telecom repeater applications, as it's marked 'GPO' (general post office)

germ1.jpg (17785 bytes)esw20.jpg (5750 bytes)< German WW2 military valves - Valvo RL12 P10, Telefunken LS50.

> Ediswan ESW20

germ2.jpg (16396 bytes)< German WW2 valves by Telefunken - RV12P2001, RV12P3000, LV1, LG1

I currently have 3 valves like the first two of these on ebay

01203002.JPG (316515 bytes)Marconi-Osram LS2 triode.

smmini.jpg (1083 bytes)smallmerc.jpg (1433 bytes)

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