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VPI SDS 45 RPM malfunction

I have a brand new SDS unit that I've used for about a month now and it's been working fine at 33 rpm, but last weekend I tried to put on a 45 rpm record and the unit malfunctioned. I was able to adjust the frequency up to 80.80 Hz, which the strobe indicated resulted in correct speed, but the voltage would flicker between 72 and 115 V for several seconds and settle at 72. It seemed the turntable was holding speed at 72, but when I put the record on and the periphery ring, the SDS kept going back and forth in frequency between 33 and 45 (up and down between approx. 60 to 80 Hz and the motor would audibly "slip" when the SDS got to 80.80 Hz and then started going back down).

Is this a matter of adjusting the unit or is the unit broken? I sent an email to VPI, but I know they are very busy so I thought in the meantime I'd ask here. Any ideas or suggestions?
actusreus

Showing 6 responses by actusreus

actusreus OP
733 posts
 
I just wanted to add that the belt does not slip at 33 RPM at all, and the platter holds the speed fine.
actusreus OP
733 posts
 
Thanks Brf. What's strange is that I had an SDS unit before, and it worked fine with that same turntable at both speeds. Never had a problem or had to adjust settings.
actusreus OP
733 posts
 
If I remember correctly, the run voltage was higher for 45 RPM, but it would adjust itself automatically once you switch from 33 to 45. Also, I'm not quite sure how to adjust voltage since it comes pre-calibrated from the factory.
actusreus OP
733 posts
 
If I can re-set it myself, why would I send it back to VPI and wait for who knows how long to get it back, new unit or not? Btw, the calibration manual may as well have been written in Chinese. I can't possibly follow it, but at the same time it cannot be that complicated since adjusting voltage only involves user accessible front panel buttons, as far as I understand. Anyone here can provide a quick tutorial? It'd be greatly appreciated.
actusreus OP
733 posts
 
Rodman,
Thank you. Is this calibration for 45 RPM only? 33 works fine at 72V and I'd like to keep it that way.
actusreus OP
733 posts
 
The unit appears to be broken, strangely for the 45 RPM function only. I tried to recalibrate it, and it was factory-set to 102V for 45, which should work fine. I increased the voltage to 115V to see if that would do the trick, and the result was the same. Thanks all for your feedback and suggestions.
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