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TRF receiver

A three valve (+ rectifier) table model receiver in oak cabinet with silver oxidised metal escutcheon and pilot lamp. For medium and long wave reception. Thumbwheel tuning, volume control (Intensifier) and reaction. With screen-grid valve, detector and pentode output valve. The HF is tuned anode and the detector is resistance/capacity coupled to the intervalve transformer. A hum bucking circuit is used for smoothing, and a hum adjusting device, consisting of grid-leak to detector brought to potentiometer across heater winding. The set uses a 6 volt 624BU rectifier.

The original price was 20 gns for an oak cabinet and 21 gns for a mahogany cabinet. There is also a DC model.
The indirectly heated detector tube has a label with the text "Columbia Radio". This label looks very much like a Cossor label. There is no other type information anywhere on the tube. It may be a Cossor 41MLF or a 41MHF. The circuit mentions a Mullard 164V.
Data Valves
Serial number: 5129
Dimensions (whd): 37  31  24 cm
Voltages: 200-250 volt ~
Made in: 1930
Purchased in: 2013
Verkocht in: 2022
Click on a valve for more information
Circuit
  Article (Wireless World October 22, 1930)

What was broadcast in 1930?

 

Listen to "On the Sunny Side of the Street" by the orchestra of Harry Bidgood, vocals Sam Browne, recorded on July 4th, 1930.

A look inside

The same chassis was used in the Columbia 331, a pedestal cabinet with a built in loudspeaker...

...and in the Columbia radio-graphophone 308 (with an added LF stage).
Advertisement in The Wireless World, September 24th, 1930. The radio was introduced at the Olympia Radio Exhibition, September 19th-27th, 1930.

This page was last edited on 23.12.2022