UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Technics SU-V60. Voltage regulator

orbanp1 · 28th Apr 2019, 1:48 pm

Hi SJM,

I do not think that R403 at 103.7k is your problem, that value is well within the ballpark!

The current through that resistor is higher than in the other channel, that is why it has higher voltage on it.
The higher current could come from higher bias current from the IC input, that means an out of spec IC. That would be bad news, unless you have a replacement IC.
The higher current could also come from a leaky C401 electrolytic capacitor.
Have you disconnected that cap and made a measurement? If not, do that!

Regards, Peter

28th Apr 2019, 1:48 pm	#15
orbanp1 Heptode Join Date: Nov 2009 Location: London, Ontario, Canada Posts: 675	Re: Technics SU-V60. Voltage regulator Hi SJM, I do not think that R403 at 103.7k is your problem, that value is well within the ballpark! The current through that resistor is higher than in the other channel, that is why it has higher voltage on it. The higher current could come from higher bias current from the IC input, that means an out of spec IC. That would be bad news, unless you have a replacement IC. The higher current could also come from a leaky C401 electrolytic capacitor. Have you disconnected that cap and made a measurement? If not, do that! Regards, Peter