B3X90U (Techniek Radio/TV)

door Kees van Dijke , Heerlen, 06.12.2013, 15:31 (4007 dagen geleden) @ elturco

Hello Elturco,

Dear Kees,

Thanks for the information. Well I am just the beginner for the electronics, I have some question.

As I compare your shematic and original, coupling capacitor is C17, am I right ? So first I have to remove it !
Then change R8(470K) to 220K.And also add all purple color caps and resistors to connect R14's leg.

Please also let me know, what will be the watt of the resistors ?

And the caps must be polar or non-polar ? correct ?

I just need your re-confirmation. This radio really works without problem and I really don't want to blow it

All the resistors are 0.5 Watt. The capacitors are polyester film capacitors with a working voltage of at least 400 Volt. These capacitors are non-polarised.

C11 and R8a are instead of C17.
R9a and C25a can be connected parallel with R9.

Note also C33 and C34 of 4.7 nF at the P.U. input decreases the low frequency reproduction. For safety reasons, it is not allowed to increase the capacitor value. To increase the bass you can try so solder a 470K 0.5 Watt resistor in series with C33, but it is then possible the maximum audio power output isn't sufficient.

regards,
-=Kees=-