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Cossor Continued
Shown left is a battery Cossor receiver model 238 from
about 1937. This set was designed
for the home without mains  electricity,
requiring HT, GB and accumulators to provide power.
It can be seen that screen printed glass tuning scales have superseded
the celluloid tuning scales from the early 1930’s, reception is provided on
long wave and medium wave. Very
nice detailing is present around the perimeter of the speaker cloth, but that
apart there is nothing remarkable about this receiver.
Valve line-up is 210VPT, 210SPT, 220HPT, and the receiver cost £5.12.6
(without batteries).
Shown left is the model 72 from about 1939.
Cossor have now bowed to the inevitable and the receiver uses a superhet  circuit.
Obviously Cossor valves are utilised on the chassis, winding up with a
2XP output valve. Notice that the
output valve, rectifier and power supply components are on a separate chassis to
the radio chassis. This meant that
the radio chassis was not as wide as it would otherwise have been, and so made
it easy to use the same chassis components in both horizontal and vertical
cabinet styles. When used in the
upright cabinet the radio chassis would be at the top of the cabinet, with the
power and output chassis in the lower half of the cabinet.
This can be seen in the comparison between the model 72 and model 77,
although these are not exactly the same chassis’s.
Notice that the on/off switch is a toggle switch at the
side of the cabinet in both cases. For
the 72 a wooden recess is created  in
the side of the cabinet, whereas in the upright model 77 a brass escutcheon
provides the mounting for the on/off switch.
The only reason I can think of for separating the on/off switch from the
volume (or tone) control is to enable the set to be switched on and hence warm
up to a known volume level, but this seems a pretty weak rationale. Valve
line-up for 72 is 41STH, MVSPENB, DDT, 2XP, 431U. Line up for 77 is the same as for the 72, except that the
output valve is a 2P, which could deliver only 2w output instead of 4w for the
2XP. I acquired this receiver with decades of dust on the chassis, and no sign
of a single component ever having been changed. The story of the
restoration will appear elsewhere on the site sometime in 2003, suffice to say
even though over 60 years old, it's still using the original paper electrolytics!
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Cossor
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