philips: 890A; Philips Allegro

Hello, friends,

I have acquired an Allegro 890A and am waiting for shipment. I have several questions about this interesting Monoknopf Philips:

On the schaltbild, there seems to be a rectifier tube (gleichrichter-roehre) at the input side of the audio output transformer. What putpose does this tube serve? I have been around radios a long time, and have been a ham radio operator for 45 years, and I have never seen this arrangement before!

Also, I want to begin gathering a set of spare roehren. Perhaps the most difficult to find will be the AM1 magisches auge. Is there anyone on RMorg who can help me locate one of these in good condition, with usable brightness?

Also, I would like to find several ABC1, AK2 and AF3 and 1561(RGN2004).

If anyone who has this radio can offer me any recommendations as to restoration, I would greatly appreciate it. I have plenty of spare capacitors for the power-supply and interstage bypass requirements.

Many thanks to everyone!

With 73,

Sandy Gerli AC1Y

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Hello Sandy,

You are most likely referring to the automatic fine tuning "traction magnet" - actually the motor driven unit which requires the second AL4 (or if the model was the Contata then it has the second EL3 output tube) and additional AZ1 fw rectifier. There is also the Toren Relay which makes this all happen.

The Service Document for the 890A describes the operation on pages A3 and A4 - with figures. . . . . .but I will omit the precise details for those who may have already translated the document.

Respectfully,

Robert

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Hi, Robert!  So that's it? A type of motorised fine tuning? Very interesting, indeed. I am anxious to receive the radio. Cabinet is in good solid shape and chassis is also. I suspect the usual needs like the HV electros requiring renewal which I'll do before I attempt putting it on my Variac.

I appreciate your input on this!

73,

Sandy AC1Y

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