Gerard's Philips B5X23A/04

252
Item nr.

Philips B5X23A/04 Table top

Philips plano models were universal in the early sixties.

**Data for Philips B5X23A/04**
Production	The Netherlands, 1962.
Bands	LW MW SW FM (87.5-104 MHz).
Tubes	ECC85 (FM tunes), ECH81 (Mixer), EF89 (IF Amp), EBF89 (IF and detector), EAA91 (FM Ratio detector), ECC83 (Audio Preamp), EL84 and EL84 (Output), EZ81 (Rectifier), EM80 (Tuning eye).
Cabinet	Wood. Size 56x22x24 cm.
Power	AC (110-245V), 75W.

The Design

Plano was the name for a line of radios started in 1958 with the B5X84A. Similar radios, with the same size and the same tubes, were sold until 1964 or 65. Several have passed through my collection, including two B5X94A (1959), two B5X23A (1962), three B5X43A (1964). The tube lineup of this radio was the same for the entire series (see tube chart), this includes virtually all Philips radios whose type number starts with B5X.

The FM band coverage differs from model to model, because during the fifties only the lower half of the band (up to 100MHz) was used. So, early planos tuned up to 100MHz, in the sixties they extended up to 104MHz, and only by the end of the sixties, radios ranging up to 108MHz were produced by Philips. Export models are an exception, of course. Notice the symmetry on the dial, with the MW stations arranged in V-shapes. Only the name of the DeutschlandSender was too long, and it had to be placed a bit higher and this disrupts the nice pattern.

Obtained	3/2005 from Jeroen Fokker.
Condition	8.
Disposed	Sold 7/2011.
Sound sample	PLAY SOUND Fifteen million Dutch people, all individuals, but with a common youth memory: a wood plano playing in Grandma's living room.

This Object

The B5X23A model was introduced in 1962, and replaced by the B5X43A in 1964. That model was the first with a stereo demultiplexer. This set was produced in 1963, as can be seen from the production markings 6/63 on the loudspeakers.

Repairing a plano is usually a pleasure because the layout is sufficiently spaced to allow good reachability with the soldering iron. Just keep in mind that the chassis should be pulled through the front of the cabinet. There are a few common problems:

The light refraction screen behind the dial is usually torned. Repair it with tape, or replace. I chose for repair with transparant tape, which should last for at least two decades.
The clutch mechanism, which changes the tuning control from the AM to the FM capacitor, is often a bit dry, so that tuning on one band pulls the pointer of the other band. Drip some oil in the clutch behind the tuning control.
The two output penthodes have a common cathode resistor (of 100 Ohms), which causes problems in case of one tube running out. So (as was argued in an article in Radiohistorisch tijdschrift 119) split the cathode circuit and use two resistors of 200 or 220 Ohms instead.
Distortion due to worn out speakers. The spiders can be tightened by treatment with Bison Kit.

Apart from these common problems, the radios are not often defective because they were quite well built, and the old tar capacitors were no longer used in 1963.

I refished the cabinet and replaced the ugly power plug. Measurement of the tubes revealed that only the ECH81 and the EZ80 wanted to be replaced; for the EZ80 I put the more powerful EZ81 (Haltron). There were two nasty technical problems, that I managed to reduce, but not solve. One, there is distortion when loud basses are reproduced. I fixed the loudspeaker spiders which made it less severe, but I think some of the remaining distortion is produced in the electrical circuits. Two, there is some signal loss between the second IF tube for AM (B3, EF89) and the detector (B4). This causes the radio to overload on strong stations. The problem was reduced a lot by disconnecting C48, 100pF, from the detector coil.

I made a memory card with a station list for the radio (right). This is a lot better than sticking stickers to the dial!

Part of Gerard's Radio Corner.
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