Hi everyone! I need help! (always...)
I have replaced all the electrolytic caps in this unit and removed all grease and oils and relubed the whole thing. It was working great and then I decided that I should do the electronic calibrations.
It should be noted that there was a change at the factory in this unit whereby C309 had changed values from 3.3uf (in the service manual) to 330uf and also there was no C315 as in the manual but there was a C316 with a value of 2200uf at 6.3V...
All things aside, the unit is the same as every other model...
Now - to the hell part...
OK - so I first did the Tonearm Sensitiviity measurements - I found that it was .995V with the arm cocked to the right and then .002V with it to the left.
Using the formula given which was .995 - .002 / 2 + .002 = .498 V
Ok - hope that was done correctly because now the little grub screw was reset for approx (as best as I could get it ) .498V
Moving on now to the Servo Gain and Offset Adjustment....
I was able to adjust initially to .72V with VR301 turned completely clockwise.
Then next I grabbed a Patricia Barber VS MOFI 45RPM LP which in the absence of a 1mm pitch test LP, had grooves leading to the label that were 1mm spaced for approx 10 revolutions.
Now I adjusted for .6V and then took it up to the space it would go to live....
It all seemed a bit weird - my wife seems to remember that the arm was now drastically offset and travelling behind the servo.
Rechecking our work, we tried to figure out how possibly this all went a bit wrong. We then tried to adjust by ear and were relatively successful, but in rechecking the Gain Voltage on VR302 we now found that that this would go no higher than .52V...funnily enough. (Also this measurement was when I had the unit plugged into a step-down transformer that brought the AC to 115V from the usual 123V in the outlet - now checking that my mind wasn't completely gone I plugged in the unit to the wall and noted that now that Gain Voltage was now .44V !!!! - back to the step-down and it went back up to .52V - and this was with it cranked clockwise....)
So, with this measurement, we did it by ear and it seemed to now work...but at the end of side the cart now goes ahead of the motor during the takeout grooves and sometimes skips back before being lifted up.
All sounds good though and seems to behave well during play...
What are we doing wrong?
It seems that others have done this operation without possible depression/divorce/10,000 yard stares into the abyss...that would be our end goal.
Thank you for reading - I have tried to be at least humourous because I wasn't very 'up' about it yesterday...much sunnier today...
I also would like to correct the model number - it is indeed the Technics SL-QL1.
I have replaced all the electrolytic caps in this unit and removed all grease and oils and relubed the whole thing. It was working great and then I decided that I should do the electronic calibrations.
It should be noted that there was a change at the factory in this unit whereby C309 had changed values from 3.3uf (in the service manual) to 330uf and also there was no C315 as in the manual but there was a C316 with a value of 2200uf at 6.3V...
All things aside, the unit is the same as every other model...
Now - to the hell part...
OK - so I first did the Tonearm Sensitiviity measurements - I found that it was .995V with the arm cocked to the right and then .002V with it to the left.
Using the formula given which was .995 - .002 / 2 + .002 = .498 V
Ok - hope that was done correctly because now the little grub screw was reset for approx (as best as I could get it ) .498V
Moving on now to the Servo Gain and Offset Adjustment....
I was able to adjust initially to .72V with VR301 turned completely clockwise.
Then next I grabbed a Patricia Barber VS MOFI 45RPM LP which in the absence of a 1mm pitch test LP, had grooves leading to the label that were 1mm spaced for approx 10 revolutions.
Now I adjusted for .6V and then took it up to the space it would go to live....
It all seemed a bit weird - my wife seems to remember that the arm was now drastically offset and travelling behind the servo.
Rechecking our work, we tried to figure out how possibly this all went a bit wrong. We then tried to adjust by ear and were relatively successful, but in rechecking the Gain Voltage on VR302 we now found that that this would go no higher than .52V...funnily enough. (Also this measurement was when I had the unit plugged into a step-down transformer that brought the AC to 115V from the usual 123V in the outlet - now checking that my mind wasn't completely gone I plugged in the unit to the wall and noted that now that Gain Voltage was now .44V !!!! - back to the step-down and it went back up to .52V - and this was with it cranked clockwise....)
So, with this measurement, we did it by ear and it seemed to now work...but at the end of side the cart now goes ahead of the motor during the takeout grooves and sometimes skips back before being lifted up.
All sounds good though and seems to behave well during play...
What are we doing wrong?
It seems that others have done this operation without possible depression/divorce/10,000 yard stares into the abyss...that would be our end goal.
Thank you for reading - I have tried to be at least humourous because I wasn't very 'up' about it yesterday...much sunnier today...
I also would like to correct the model number - it is indeed the Technics SL-QL1.
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