Five-valve battery radio

Superheterodyne "radiomodulateur". In the same year the four valve RM4 and the six valve RM6 were introduced. Walnut cabinet with black aluminium front. Original valves for this set given in the documentation are: R43, R15 or 6/100e, R36D or 6/100e, R50 or CL104 (or R15 or 6/100e). A R43M bigrille is still available.
 Data Valves
Serial number: 1319
Dimensions (w×h×d): 38 x 34 x 30 cm
Made in: 1926
Purchased in: 2006
Click on a valve for more information
Circuit

What was brodcast in 1926?
 

Listen to "Tea for Two" by Fredo Gardoni and his accordion, acc. by banjo, "jazzoflûte", and "trap-drummer" recorded in 1926
 

Interior
Above, the chassis as it was when I bought the radio. The crooked rectangular object beneath the upper spindle is suspect and clearly not original. It is in fact a "Wireless" combined leak resistor (2M) / capacitor (200 pF). This combination was removed and replaced by an original capacitor. The grid leak resistor was placed at the other side of the chassis, where it belongs. The crooked transformer is a Lemouzy type one; this transformer was removed and replaced by an original Ducretet transformer (see picture below).

The restored chassis.
Back
Interior
The horizontal wooden brace behind the metal front was missing. In the middle of this this brace, there is a brass snap connection for the lid. The brace was replaced by a new one with the lower half of the original Ducretet snap connection. This work was done by furniture restorer Wiego Bergsma, Utrecht. For use with a frame antenna, the left coil has to be removed and replaced by a special plug.
Coils
Radiospire No 48R (200/700 m) and transformateur No. 225T came with the radio. Transformateur 225T (long wave) can not be used together with Radiospire 48R. Coils 70T and 48R, shown above, are a better combination.
Bottom
Radio stamp and serial number

Picture from a Ducretet advertisement

This page was last edited on 27.04.2019