TRF receiver for AC

Oak cabinet, black aluminium front and bakelite knobs. Design by Otto van Tussenbroek. Made by Van der Heem & Bloemsma, The Hague. This firm released the same model using their own name: the H. & B. 34.
Het Volk, dagblad voor de arbeiderspartij, September 10, 1931
The radio was presented at the Jaarbeurs Autumn Trade Fair in Utrecht in September 1931.
The knobs from left to right: primary tuning, reaction control, secondary tuning, wave lenght switch. The two scales are illuminated by a bicycle lamp (6V, 0.3 A).
At the top of the chassis are the connections for a speaker and a gramophone, as well as sockets for antenna and earth.
Date stamp on one of the condenser blocks: October 6, 1931.
The original price was f 155,-
Strangely enough there is another Erres KY111: a tombstone model with a built-in loudspeaker (see pictures below.) That radio was marketed by Lindeteves-Stokvis in the Dutch East-Indies in 1934.
Data Valves  
Serial number: 24357
Produced: Ī 150
Dimensions (w◊h◊d): 46.4 ◊ 26 ◊ 22.2 cm
Made in: 1931
Purchased in: 2006
Voltage: 125 V
   
Click on a valve for more information

Replacement circuit

What was broadcast in 1931?

 

Listen to "Sweet and Lovely", by the Orchestra of Jerry Hoey and vocals by The Les Allen Trio, recorded in November 1931

With Erres loudspeaker (1930)
Back
Valves (left to right) C443, E424, E452T, 506K

A look inside
A second copper coil base is situated behind the mounting plate with resistors to the right, below the central capacitor block. The Philips 4000 l.f. transformer (below left) had to be repaired.

Advertisement for the KY111 tombstone in Het Nieuws van den Dag voor Nederlandsch-IndiŽ, May 12th, 1934...

...and in the Nirom-Bode (1934)

This radio has the following valves: E446, E446, E443H and 1823. The radio uses resistance-coupling, as transformers would not have a great lifespan in humid conditions. The wave lengths are 12-40 meters, 30-85 meters and 75-200 meters.
Erres KY111. Picture from a leaflet

Deze pagina is voor het laatst bijgewerkt op zaterdag 27 april 2019