SX 1250 Phono issue still exists

lets go over this again .
jump 4 to 7 and equal sound ?
25 to 15 no change ?
15 to 7 no change . ?
24 to 25 no change ?
that leaves the wiring from the phono socket to the switch . or there is low signal from your source .. have you tried swapping phono inputs yet ? if not give that a try first . if no use check that wire .
did we try 25 to 7 jumpered ?
Ok now i jumped 4 to 7 and not the same voltage, pin 10 . 16-18 mv . pin 1 . 0.3 mv . something has moved or changed
 
with jumpers connected to 4 and 7, phono input 1 sound coming out on left side speaker, nor clear but definitely song playing. Pin 1 goes all the way down to 0.1 mv . 10 jumps from 15-16 mv
 
now it looks like there is an intermittent problem with the phono board as jumping 4 to 7 earlier worked but now it doesn't
is your meter on AC millivolts ? . it should be to see if music is playing .
its that or the tape monitor switch affecting it ..
 
now it looks like there is an intermittent problem with the phono board as jumping 4 to 7 earlier worked but now it doesn't
is your meter on AC millivolts ? . it should be to see if music is playing .
its that or the tape monitor switch affecting it ..
Its on ac mv set at 200 all the switches are set to off except speaker and phono 1. I did get the mic to work but again only on left side I will touch all of the wires again, work all switches then try to jump 4 and 7 to see if i can get 1 to read again
 
it is looking more and more like 2 problems .. one with switches and other phono board right channel .. might be simply a bad solder joint .
 
I checked all wires, reworked switches no change 4and 7 connected pin 1 0.1 mv . pin . 10 . 16mv . i get sound out of speakers but only after about a minute or so. I will check all solder connections . Strange even if i move the switches while on right channel no sound at all, tried volume up and down many times.
 
With all of the information that i have received from all of you knowledgable people, i agreed with the assessment that there must be a bad solder joint or such. Im sure you guys would have found this quicker but with just a multimeter and eyes this was hard to see. After going over every soldered joint and touching every cap resistor etc, i noticed that the ground bar on the equalizer board (im not sure that is what it is called) above R11 was broken, it had a hairline break, when i touched it with tweezers it came apart. I replaced it and now i am getting left and right sound on phono. Im sorry if i frustrated some of you while you were trying to help but sometimes i do not explain myself well enough causing questions and answers that were not necessary, in the future i will be very explicit with my answers. Its amazing that this could cause so many issues. thanks pete
 
Its amazing something so small causes such a large problem, and also thank you for your time
Yes I think we all, me included jumped to more complex issues than the simplest thing.
I should know as I have had two very similar issues yesterday, one was a tape deck with the left channel distorted, the owner said "it just suddenly started doing it".
So I had the lid off expecting to get into the playback amp somewhere where I would find a failed transistor, but I suddenly thought to myself, "simple things first".
Well I cleaned the heads, and I tell you, I have never seen so much crap on a playback head!!
Cleaned it, put a tape in, perfect clean audio!!

I have showed the owner how to clean a tape machine now!!

So there you go, yes sometimes the simplest things can have a great effect and fool even the best....
 
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