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Old 13th Jun 2009, 9:46 am   #9
Mach One
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Join Date: Sep 2005
Location: Shoreham-by-Sea, West Sussex, UK.
Posts: 610
Default Re: Philips BG413A = Philips 413A?

To satisfy my own curiosity, I have downloaded the circuit diagram of the 413A and the 411A (which is similar to the more common 310A / 341A) and they are quite different beasts.

The 413A has a superb Long Wave coverage extending from 150kHz right up to around 425kHz and uses its own LW oscillator coil to achieve this. Most sets use the MW oscillator coil with a capacitor across it to bring the frequency down.

It also has a typical for the time complicated switched sound shaping circuit which allows the user to change the tone as it were of the loudspeaker. It looks a very nice set...
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