Hi Everyone, I really need some help as I only have a basic understanding of electronics. I want to clean, replace some caps and adjust the voltages on the speed controller board of my TD125 MK1. There seems to be a lot of info for MK2, but not so much for MK1. Attached Is the digram for my board. The problem I have is I do not know what points to attach the multimeter too, So I can check the voltage for each speed, as in I put the black lead on what point and the red lead on what point to check the voltages.
45rpm set (R18 for 8V on the MK1)
33rpm set (R17 for 5V on the MK1)
16rpm set (R15 for 2.5V on the MK1)
And do I go AC or DC?
I really have tried to read the service manual, but I do not fully understand it.
I also have access to an oscilloscope, I read I should check that motor has a smooth sin wave, where to put the point and the ground to do that?
Sorry once again.. I really want to learn how to do this, I just need someone show mark the digram or explain it in like put the red lead on R15 and the Black lead on whatever to find the voltage for 33rpm
Please and thanks once again
45rpm set (R18 for 8V on the MK1)
33rpm set (R17 for 5V on the MK1)
16rpm set (R15 for 2.5V on the MK1)
And do I go AC or DC?
I really have tried to read the service manual, but I do not fully understand it.
I also have access to an oscilloscope, I read I should check that motor has a smooth sin wave, where to put the point and the ground to do that?
Sorry once again.. I really want to learn how to do this, I just need someone show mark the digram or explain it in like put the red lead on R15 and the Black lead on whatever to find the voltage for 33rpm
Please and thanks once again
Attachments
If you plan to recap I would suggest to do this first.
It could be wise to renew the trimpots as well.
Measure the current ohmic values of the wipers to outer pins and write them down.
You can adjust the new ones to these values before you replace them.
Here's the complete manual. Look up your serial number to make sure you have the correct schematic.
There are two of them in the manual.
It could be wise to renew the trimpots as well.
Measure the current ohmic values of the wipers to outer pins and write them down.
You can adjust the new ones to these values before you replace them.
Here's the complete manual. Look up your serial number to make sure you have the correct schematic.
There are two of them in the manual.
Thanks for that, your manual is better than mine. I do plan on recapping first but once that's done I want to adjust the trim pots to match to what I believe is the correct values from what I am reading I just do not know what points do I stick the multimeter on to get the readings for 16rpm,33rpm,45rpm.
45rpm set (R18 for 8V on the MK1)
33rpm set (R17 for 5V on the MK1)
16rpm set (R15 for 2.5V on the MK1)
At the moment, the turntable is slow to start and has trouble maintaining speed, ..It has a new belt, and has the original caps.
My Serial number does not match..
The speed control board looks like the circuit I posted earlier
My Idea was to adjust using only multimeter, if that does not work replace caps and then adjust.
45rpm set (R18 for 8V on the MK1)
33rpm set (R17 for 5V on the MK1)
16rpm set (R15 for 2.5V on the MK1)
At the moment, the turntable is slow to start and has trouble maintaining speed, ..It has a new belt, and has the original caps.
My Serial number does not match..
The speed control board looks like the circuit I posted earlier
My Idea was to adjust using only multimeter, if that does not work replace caps and then adjust.
Your Snr. is higher than 24308 so this points to the second schematic in the manual.
Discard the other one.
On page 4 you'll find the Electronically adjustment.
Try to understand what's written and ignore the warning about the overloading of the meter range if you have a digital meter.
All measurements are made with the meter connected between the black and blue leads on the motor.
Continue on page 5.
Hugo
Discard the other one.
On page 4 you'll find the Electronically adjustment.
Try to understand what's written and ignore the warning about the overloading of the meter range if you have a digital meter.
All measurements are made with the meter connected between the black and blue leads on the motor.
Continue on page 5.
Hugo
