I've recently purchased a KAB speed strobe which has indicated that my Scout is running very slow (notches moving counter clockwise); over 100 notches in 60 seconds.
I have the newer black belt with unknown time on it; I've cleaned the belt, motor grooves and platter grooves. I get power from a dedicated 15amp plug, through an Audience AR-6 conditioner and stock power cord to the motor. I've tried using different notches on the upgraded 300 rpm motor pulley, with little effect.
I suppose the cheapest experiment is to buy a new belt, and lube the spindle bearing (for which I'll have to purchase oil) and see if that changes things. Short of buying the VPI SDS, are there any other actions which may help here for little money? Perhaps a used Variac would essentially do what the SDS does?
Well, I think I've just discovered some major power fluctuations in my 'hood!
With the motor positioned correctly, I tried Elizabeth's trick; I counted 103 1/3rd rotations in 3 minutes. I tried the KAB again and it was reading fast (????)!
My assumption now would be that the power to my home fluctuates greatly throughout the day? We have a new 200 amp panel, new wiring and a dedicated line to the TT. How do I check voltage from the wall socket; can I do this with a multimeter?
It won't so much be voltage that will cause your problems, (if it is a electric source problem) it will be line frequency varying.
While the VPI SDS can vary, and ramp down voltage, the Platter speed is set by varying the output frequency of the SDS.
While not impossible, it is rare that line frequency will vary that greatly to cause you a considerable slow condition one time, and then run fast another.
And I sort of doubt your KAB Strobe Disc is at fault.
I assume your Scout uses the newer style Inverted Bearing. These are to be lubricated with grease, not oil. A simple Lithium Grease will be suitable.
I suspect your problem to be your conditioner. Plug direct to the wall, not the power conditioner, and then take a measurement with the Disc. If you have the stepped Motor Pulley (the one with a number of ridges on it), you can then set the belt upon the ridge-groove of choice to get as close to 33-1/3rpm as you can. Hope this helps. Mark
Bshappered, your VPI has a synchronous motor I beleive. That means it should sync up with the 60 cycles from an outlet. The 60 cycles is almost always accurate. The voltage will vary a lot in some places, but not the 60 cycles. You could check the outlet voltage with a multimeter. Read the instructions, and be careful. You could also get a P3 Kilowatt meter that just plugs in. Your voltage could be from 114 volts to 126 volts. With that voltage variation, the VPI should hold its speed. Something else must be going on, unless you really have voltage out of the 114-126 volt range. The 60 cycles will keep it right with 114-126 volts. A link for a P3 Kilowatt, that might be sold at your local home center. [http://www.mcmelectronics.com/product/28-10985&CAWELAID=220321019]
Also, the P3 Kilowatt can be left plugged in, and you could watch the Volts or cycles readout. The cycles most likely will stay between 59.99 to 60.00 cycles. That's fine. If you have lights flickering, bulbs burning out, call your electric company, or electrician to get there quickly. That would be in case they left a loose connection somewhere. Not common, but possible, since new work was just done.
Ok, the platter is consistently measuring fast, now. I've taken measurements with the motor plugged into: a different circuit; wall receptacle of the dedicated 15amp; the power conditioner, all with the same results. I've tried using different steps on the pulley with no noticeable change. I've tightened up the set-screw on the pulley (which was loose) and used a 45 lp on the platter to replicate stylus drag.
I'll try measuring the speed of the platter at different times of the day, but as others have mentioned, voltage should not effect the platter speed?
I'm not sure how familiar you are with your TT. Do you know that you can vary the speed in small but noticeable increments by moving the belt up and down on the spindle? The larger part goes faster, the smaller part slower.
Just checking - it would suck to go through gyrations and miss this important detail.
One of the ways I've checked my turntable speed was with... Guitar Tuner. I perfectly tuned my guitar and followed solos and chords of few bands I know and figure out that i'm out of tune from original recording by approximately 1/4 of a tone up. That signalled me that my turntable belt got thinner and longer needing replacement. Also you can play in unison same digital version of recording through your computer and see which one 'runs' faster. If everything is in-tune and/or runs with same speed than strobe is wrong and needs moneyback or free replacement. The other suggestion is to realy check if you're using original VPI belt and if not, you'd better order it.
According to Mike at VPI- The way to "freshen" a VPI belt is to toss it into boiling water for 15 seconds, then wipe it w/alcohol, then put it in a baggie w/some baby powder and shake it up. Remove, shake off excess powder, volia.
Your orignally 100 notches in 60 seconds is a 3% error, I if read my KAB instructions correctly. That is huge.
How fast is it running?
I am surprised that using the different steps on the pulley have no effect. That is normally how you adjust the speed. I have a Scout with the 300 rpm motor. It is on speed at the top notch, and noticible fast at the bottom notch.
There are differnt pulleys for different platters. Do you know that you have the correct one? I remember looking at a used 300 rpm motor, but it had the wrong pulley. So, I bought a new one with the correct pulley. Just a thought.
Ok, for those of you following this thread: I've just switched out the 300rpm motor for the original 600 rpm model, and the speed is almost perfect! There must be some issue with the capacitor (as someone previously mentioned), or perhaps the pulley, or motor itself.
Pretty much all of us, have been drawing straws as to what your issues were, and I guess all we could do is make suggestions. When problems such as these arise, one must hold every component of the drive system suspect. And then methodically check each.
While I'm not sure of this, because I have no experience with the 300rpm motors VPI uses, so I am not sure if the Motor Run Capacitor is typically the same value for either 600rpm, or 300rpm Motor?
Thos are perhaps questions others here can answer, or VPI?
There were a few unknowns about your situation, whether the Table was bought like this, or did you make the 300rpm Motor swap recently yourself, or? I'm getting the impression you may have bought the 300rpm Motor used?
That there was either A., a problem with the Motor itself, and you bought a bad one? Or B, that this Motor requires a different Run Capacitor, which was typically included in the purchase when gotten new from VPIm but you didn;t get included with the purchase? Mark
I thought I would update this post for future reference. Initially, the pulley was loose on the motor drive-shaft which caused the pulley to slip, resulting in slow platter speed. After tightening the pulley's set-screws, the platter ran fast.
At this point I contacted VPI who suggested I send in the existing 300 RPM pulley, as it was probably for a 12" platter, not the 11 1/2" acrylic, Scout platter.
So, I've just installed the new pulley, sent from VPI, and everything is perfect; solid speed, good sound.
I don't mean to resurrect a dead thread but I am having the exact same problem. I bought a scout new almost a year ago and have noticed the sound seemed lower and slower than the CD when I did an A/B test. I just now got around to timing it and am consistently getting about a -3.2% error in speed, meaning it takes roughly 3min 5.7 seconds for the platter to go around 100 times. I haven't gotten a hold of VPI yet since they aren't open Monday, but wonder if I might be having the same pulley issue. The motor I have is the stock scout motor,and wasn't bought separately from the scout.
Its a lower pitched sound, not lower volume. I have tried the pulley positions with no effect. Mike from VPI told me to check if the pulley is loose, which it was not. He said the next step would be sending me a replacement pulley. I'm not sure how the pulley could be messed up since it is such a new table, but it is possible.
Is it possible that the belt has stretched? Take the belt off, boil it in water, then reinstall and try again. VPI tip is to put the belt into a samall bag with a little bit of talc powder, give it a shake, then reinstall the belt; this powdered belt helps to negate any slippage between the belt and platter.
You say the pulley is tight; a loose pulley was my first thought? Take off the platter and confirm the thrust bearing is adequately greased ( I'm reaching here).
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