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I recently bought a SP-10 Mk2A, including the Service Manual. A friend with good electronics experience and a full test bench went through the measurements and adjustments section and everything looked good. However, all three speeds run fast, which was verified with an external strobe.If you might be able to help, send me an E-mail (Subject: SP-10 help) or post yours so I can provide more detailed info.
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Is there an adjustment for that on this table?It might explain why the internal strobe is showing as correct.
The built-in strobe shows stable and correct running at all three speeds. When I set up the table on a temporary board with tonearm to audition, speed was obviously off. This was when I used an external strobe disc on the platter which indicated it was running fast at all speeds.
Since the strobe runs on the same crystal as the motor drive it will not show changes due to crystal circuit errors.Check the waveform at pin 5 of IC3 on the logic board for correct period (1.14 us). If it's off, adjust trimmer C210. If it's right, check pin 1 of IC5 and so on.
Mark, thanks for responding. I'm not too technical so will need to relay your suggestions to my friend who is. Therefore, I need to be clear on your recommendationsFirst, did you note I have a Mk 2A, not a Mk 2? As I understand it, they are quite different. Looking at the Service Manual for the 2A, no IC3 or IC5 is shown. All the ICs have 3-digit numbers: 10?, 20?, 30?.
If this helps, the frequency to IC301 was verified at 273.30 as specified. So, what next?
I don't have acess to a manual so I can't help.
A few months ago, I posted a technical question about my SP-10 MK II which Mr. Kelly correctly diagnosed. Though I ended up taking it to a professional tech for repair, Mark's analysis was right on. In his profile, he does not accept unsolicited email, so hopefully he'll read this and offer his insight into your problem.Regarding oiling, there is a hole for oiling the spindle if you remove the platter and its three retaining screws on the MK II, but I highly doubt this would cause the table to run fast.
The symptoms described are too general for a specific diagnosis.Since the problem affects all three speeds I assume it has to do with the crystal circuit. I would start by looking at c210 (the crystal trim capacitor).
Good luck.
to add oil whenever the motor is unable to maintain the proper speed despite adjusting with the pitch wheels. The speed problem goes away after lubrication. My 34 year old owner's manual says add lubricant every 2000 hours, but I never get that far before speed problems arise.
Of course, my SP10 is a servo controlled motor versus the quartz regulated unit that you have. I have no technical background, so take this suggestion accordingly. Bill.
My SP-10 had a oil port under the platter. The SP-10 Mk II's I have do not. I suspect adding oil would help the SP-10 Mk IIA if possible.
Here's a link.
HenryA 12-gauge shotgun is the ultimate arbiter of disputes - G. Gordon Liddy
If so, those usually have a var. resistor to dial in the 'default' Zero-point. I dont have a Service manual, but thats how they do it on the lesser SP models.Good Luck..
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