sx-535 no stereo light

[gtmcgar1]

Just finished a recap on this unit and everything appears to work except the stereo light! The amp was non functional before the recap. I'm waiting on the SM it's in the post but I thought I'd ask the experts.
Signal strength on FM 3-4. Measured bulb resistance at 25ohms-good. I did change the pointer bulb to led and all others to led. I rebuilt all boards with Marks recommendations, all inputs work and sound great. I did not spray anything on the tuner air cap, just a light paint brush. The unit appeared original but filthy.
Some voltage checks PS board
2 -26.4v
6 26.4v
10 -40.7v
12 13.5v
13 13.5v
14 13.5v - never drops to 6v
16 30.5
17 30.5
Also checked tuner pins 15,20 @ 13.4v and pin 4 1.98v
Any advice much appreciated.

 

[john stumpf]

is that the tuning cap now?!!! start with a vacuum then canned air or low pressure compressed air. open up the cap and spray with a non residue electronic's cleaner. buy two cans,vacuum some more use deoxit d5 on the brass shaft ground wipers let sit 8 hrs.repeat, exercise the cap make sure the shaft wipers are corrosion free, respray with contact cleaner let dry over night lube shaft wipers with deoxit fader lube shaft bearings with light machine oil (i use sewing machine oil) dont get ANY on the fins. then when everything is lubed corrosion free and dustless squeaky clean try again

 

[gtmcgar1]

Clean up has been done already, sorry.

 

[tsd71]

is the unit pushing out stereo FM? Deox the hell out of the selector switch again, sometimes that will make it come back on.

 

[gtmcgar1]

Just checked FM on headphones - no stereo, compared to phono which has obvious stereo. Deox of the selector switch didn't help. I also cleaned the tuning cap as per the instructions, I have better signal strength but no stereo light. I also just got the SM so I'll take a look at that and see how the other voltages stack up, a bit wary of probing the IC though.

 

[gtmcgar1]

Measured voltages on HA1156, i need expert help please!
1-13.3 2-3.0 3-5.0 4-11.3 5-11.3 6-13.3 7-0
8-0.02? 9-2.2 10-1.51 11-2.13 12-2.3 13-2.3 14-3.2
looks like i have a problem on pins 8 and maybe 11
Any pointers appreciated. I did find a bad trace on c11 of am-068 switch board, replaced cap and
soldered to the trace, measured continuity ok.
much thanks

 

[gtmcgar1]

one more piece of information that may or may not help the troubleshooters out there. I measured q8 and
q9 collector voltages, L reads 7.2v as per the SM, R reads 7.73v wondering if this is a significant difference.
I also rechecked the lamp, turns on with a 9v battery attached so I guess its good. Any help appreciated.

 

[zebulon1]

Is C50 a Sanyo sky blue cap? Its listed as a .47uf 10v CSSA. They turn into resistors.
Replace it with something new. Preferably a film. Or a ULK?
Pins 8 and 9 should have the same voltage and are actually a loop back into the chip.
It (C50) and pins 8 and 9 are part of the stereo indicator circuit.

 

[gtmcgar1]

No blue Sanyos left, its a panasonic film cap and I just figured it out. I adjusted the VCO ever so slightly and its all good. The remaining problem I have is a rough VC and a slipping dial cord, working on that now. Thanks for all the help a search of the site saved the day.