The Cosmos A45 is a bright emitter receiving triode that was introduced by Metro-Vick Supplies, a subsidiary of the Metropolitan Vickers Electrical Co Ltd, in 1925. The first production had a metal base skirt and later types had the bakelite skirt as shown in the picture above. The M over V logo can also be seen as can the filament rating of 4.5 Volts at 0.6 Amps. Both versions employed the same 30 mm wide envelope.
The valve was a general purpose type with an amplification factor (μ) of nine. The control grid voltage range was between 0 and -6 Volts.
The has a closely spaced cylindrical anode and control grid. The filament is a straight tungsten wire that is kept under tension by a wire spring at the top.
The wide glass tube envelope is 30 mm in diameter, and excluding the B4 base pins, is 92 mm tall.
Pin Connections
B4 |
1 |
2 |
3 |
4 |

|
a |
g1 |
f |
f |
Absolute Maximum Operating Conditions
Triode |
Vh |
Ah |
Va |
Vg |
ra |
gm |

|
4.5 |
0.6 |
30-120 |
-6 |
20k |
0.45 |
This exhibit was last updated on 02 December 2007 |
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