Philips India radio 15RB697 (Algemeen)

door Pandu Rajan , 02.12.2020, 13:05 (1452 dagen geleden)

Dear members

I am restoring the above set. I am attaching the schematic drawn for each band. I am facing problem in the SW4/SW3 band. When I am applying RF signal to the antenna socket - 17.2 mhz on the low frequency side and and 25.3mhz on the high frequency side I do not get any RF tone. I checked all the band switch contacts but they are all O.K. The coils S12/S13/S14 and S6/S7 are O.K. The capacitors C17,C20,C26,C19 are O.K. The coils are common to the SW3 band. The gang condenser is O.K. The MW band is working fine. I checked everything but no RF tone.All the connection are original Finally I shifted the connection of C17 from S12 to S13 and now the bands starts working O.K. This type of problem I have faced in some sets earlier also and shifting of the connection solved the problem. I am unable to understand as to why the RF tone does not come when the connection is to S12 and the tone comes when it is shifted to S13. What is the advantage of the double coil S12,S13 and what is the function of capacitor C20?

Best Regards
P.Rajan