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

Anexos:

• d_telefunken_bajazzodeluxe201_sch1a (289 KB)

Agradézcalo al autor si Vd. encontró ayuda con la respuesta.

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

Agradézcalo al autor si Vd. encontró ayuda con la respuesta.

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

 

Agradézcalo al autor si Vd. encontró ayuda con la respuesta.

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.

 

Agradézcalo al autor si Vd. encontró ayuda con la respuesta.