telefunken: 3611; Bajazzo de Luxe

Good Morning,

 

I'm trying to fix a bajazzo de luxe radio that has evidently problems in the final Low Frequency amplifier.

A AD 155 transistor seems not working (completely dead) and I looking for a substite in ebay.

Are both AD 155 transistrs PNP geramanium transistors??? The schema that I found here shows one as NPN transistror.

 

regards

Simone

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• d_telefunken_bajazzodeluxe201_sch1a (289 KB)

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Hi Simone

Looking at the schematic I downloaded years ago, both trnsistors of the final AF stage are of pnp type (Emitter arrow tip against baseline).

It is recommended to use a suitable replacement (DC amplification "Beta" similar with the good one, measured at the working point) or use a matched pair.
Imho 2SB367 should also work instead of the proposed replacement type AD162.

Moreover I recommend to inspect the wiring around and the windings of the output transformer in order to eliminate the possibility of the same failure again.

Good luck!
Kind regards, Marc

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Grazie per la risposta, sei stato gentilissimo.

Ho trovato su e-bay.de due transistror AD 162 nuovi per soli 2 euro e li ho comprati subito!

ti farò sapere.

 

buona serata

Simone

 

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Yesterday I worked with the radio.

I have substituted the defective transistror with the substitute.

Now it works very well.

thank you for the advice.

 

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