Sansui C-2102 problems with powersupply ?

Hello,
After repairing and overhauling a C-2102 preamplifier, the following error appears.
The relay LRL 1, which is connected to the connector with pins 31...32...33 on the power supply board, switches on and off rhythmically.
All components in the circuit branch on the power supply board are intact and as soon as I remove the on/off LED from connection 34...35 of the power supply, the preamplifier works perfectly.
Can someone explain to me why this error occurs and perhaps give me a tip as to where I should look? Thank you in advance for your effort and I hope you all have a nice day
 
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Without LED there should be 23.5V before the safety resistor R1. Measure the resistor (2.2k) and check if the LED is working.
Diode reading on a DMM should measure no short or test with a 1.5V battery and a 68ohm resistor.

Hugo
 
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PSU schematic:

PSU.jpg
 
@ulogon
Thank you for the enlightenment, never seen or heard that before(y)

Well, a lot of things are better with a good night's sleep.
Had a few hours of work on the device yesterday and (I have to admit) a beer or two....
Then a quick glance at the manual (no time to change glasses) and I was at a loss. I somehow misassigned the power supply to the LED.
OK, maybe it was 4 beers🥴

This made me focus too much on the relay voltage part of the circuit and neglected Q7. My big mistake, sorry
I'll look into it again later and report back.
In any case, thank you very much for your information and statements and have a nice day☀️
 
@ulogon
Thank you for your advice regarding safety. ;)
I would like to put it this way, especially because I like beer, I'm careful. You can no longer enjoy beer when you are dead.

But to be serious, I drink these 4 beers in a period of about 6 hours, so it's more of a mixture of beer and "see the forest for the trees" because I've been looking at the device for too long.o_O
But you are absolutely right when you point this out, because even if you are practiced and are constantly "tinkering" (or maybe because of that) a mistake can quickly happen!!!
Have a nice day and best regards
 
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Small cause....big mistake...
When measuring with the oscilloscope, I discovered that the supply voltages were correct, but the voltage for the LED had a high ripple superimposed on it. When checking mC18 it turned out that the value (despite being a new part) was less than 10uF. Instead of 22uF, I used 47uF (bridge rectifiers are resilient enough) and now the preamp runs stable.
Then first have a beer :ROFLMAO:

But joking aside, it's really a bit early for this

Thanks again for your participation and see you next time