286
Item nr.


Teletone 111 Mini radio

AA5 converted to European.


Data for Teletone 111
ProductionUSA, 1948.
BandsAM (530-1700kHz).
Tubes12BE6, 12BA6, 12AT6, 35A5, 35W4.
CabinetWood. Size 29x18x17 cm.
PowerAC 110V, converted to 230V.
DocumentsSchema.

The Design

AA5 or All American Five is what these simple sets are often called. European cheap sets, like this Philips BX200U, are usually more complicated because they are multi-band and multi-powered.

Yet, the reception performance of these simplest American radios is often very good. A few differences with European radios jump to mind. American radios often have the loudspeaker mounted on the chassis (while European radios have them fixed inside the cabinet), which makes it very convenient to pull the chassis. And loop antennas are very common; I've seen them on almost all my American radios, including this RCA Victor from about the same era. In European radios one would more likely find a ferrite rod. Most loop antennas are parallel to the radio's back, but this one is perpendicular to the back. Remember, to receive a station, the plane of the loop should point to the transmitter. So with most radios with loop aerials, you receive the stations left and right of the radio, but with this one you receive the stations in front of and behind the radio. This would also be common with a ferrite rod, placed in the length of the radio.


Obtained9/2006 from A. Visser.
Condition7; cabinet woodwork is a bit smudgy.
Sound samplePLAY SOUND   Singing in Taizé style.

This Object

The radio had undergone a few repairs and a big modification before it came to me. A few capacitors were replaced, including the filter caps. The set was converted to 220V by the addition of a couple of series resistors. Of course, these produce a lot of heat (about 15 to 20W because the heaters of this set take 150mA); a bit of a problem because the wood case was not designed for this heat.

The inside picture (left) shows how the tiny chassis with the loop antenna on it, just barely fits in the wood case. I didn't trust the replaced filter caps (Italian jobs with paper coating, photo right) and replaced another five capacitors.

Reconversion to 230V

In March 2018 I modified the power supply again in a different rewiring to make the set suitable for 230V operation. Like in the Sanshin, I connected the two main loads (Heater string and plate supply) in series, with a 2uF capacitor over the B+ supply. This reduces power consumption from 38 to 23Watt. A capacitor is also very cheap.

The radio plays like a charm and is very sensitive.


Part of Gerard's Radio Corner.
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