Vpi plc question?

I'm not sure what you're referring to as "three digit calibration." I have two PLC's, and they have two switches and two knobs on the front. One switch controls power on/off. The knobs are for fine speed control at 33 and 45 speeds. The other switch flips between 33 and 45. The PLC is supposed to be used with a strobe disc. VPI makes one (I think mine may have come included with the PLC), but there are many others. Observing the rotating disc in a darkened room under an incandescent bulb will allow you to adjust the fine speed controls at 33 and 45 to correct speed (when the lines stop migrating around the disc). The correct settings are likely to vary between different turntables because of age, wear, lubrication, etc.

VPI recommends that it may be better to change speed control using the turntable's mechanism, i.e., for your HW19II, slip the belt onto the other pulley, rather than to flip the switch on the PLC. I found using the switch was perfectly OK, and I wouldn't have to recalibrate my fine speed control every time.

If you live in the USA or Canada, set it for 60hz. That is the frequency of your AC line. Dial in 600 on the PLC. That will give you the correct speed. To change platter speed to 45rpm, move the belt to the wider portion of the motor pulley.

Should call my buddy with the 19 but the strobe sounds right.Your deck dosen't have a dual notch on external motor for speed change?My guess would be the stobe to be used to check what you have now with the PLC.Or do what everybody say's and pony up for th e better drive controller.Folks always say it's th best upgrade they ever made (and that usually includes listing carts and phono sections).Not cheap at $700 used but whattya' gonna do?I hear it know dials in dead accuarte when checked with the stobe.Call Mike (head tech) at VPI an he'll set you straight (which he has done number of itmes going with cheaper option for my Aries).Not much help bu all the best.
happy Holidays
chazzbo