Need to adjust the speed every time I turn on turntable


Need to adjust the speed every time I turn on turntable.This is a belt driven Oracle Delphi II with Origin Live motor and Origin Live Control Board and Origin Live Power Supply.  I am guessing it can be the belt, motor, control board and /or power supply.   How do I determine what is not working?
dcaudio
I do not think so testpilot. He is setting the motor speed when it is cold. It should be the same next time he checks it cold. dcaudio, next time you start up check the speed but do not change it. Get an idea of how many dots drift by a fixed point in 10 seconds. Lets say it drifts 5 dots in 10 seconds. Check the speed again when it has warmed up for 30 minutes. How many dots does it drift now. Let us know what happens!!
This is a common problem with BD tables. It is caused by a combination of belt slippage (which can be cured with proper tension) and belt creep which cannot be cured, but can be compensated for with feedback. No matter how accurate the motor speed, without feedback the platter speed will vary over time due to a number of variables that cannot be controlled.

SOTA now sells a PSU and tach with feedback that will keep the platter on speed regardless of variables such as belt diameter and durometer, stylus drag, bearing oil viscosity, temperature, belt creep etc.
https://sotaturntables.com/product-category/eclipse-series/
There is of course the well-proven quartz oscillator based PLL method used in better direct drive turntables. 
one thing to consider is your power going to your house changes a few volts all the time that alone will throw off a turntable with out compensation.  

My place fluctuates up to 10volts depending on the time of day and temperatures. 
glennewdick
one thing to consider is your power going to your house changes a few volts all the time that alone will throw off a turntable with out compensation.
No, it won't. Turntables don't rely on AC voltage for speed regulation. The ones that use AC motors are synchronous to the line frequency, which is subject to only very tiny deviation by the very nature of AC distribution systems. Those that use DC motors employ regulation in the DC power supply.