Most of the time, my Sony PS-LX430 turntable runs too slow. On the occasion when it'll run at the correct speed, it will sometimes suddenly speed way up for a few seconds then go back to normal. Other times, it'll play OK then suddently slow down, where , as I said, it remains most of the time.
When it's too fast or too slow, it's at neither 33 RPM nor 45 RPM.
Because it occasionally runs too fast, it doesn't seem likely it's a stretched-out belt. Any suggestions on what the problem can be?
Some turntables have a dc motor that has a built in speed control. If you can take it apart and look over the motor and find a small hole on the bottom of it, that may be the adjustment control. Maybe try a little contact cleaner there and see what it does. Just my 2 cents in. JTT
As i was once a prefered sony repairer my memory evades me as to weather or not it is a direct drive or belt drive t/table. if it is a direct drive then as the previous reply suggests try that one out otherwise replace the actual motor itself.
There are several cheap non orgional brands out there such as the generic dai ichi brand ccw or cw (counter clockwise or clockwise this is normaly noted on the back of the motor along with voltage ratings etc) If there is a small hole also in the back then it is surely a speed controlled type.
If it is a belt drive type the belt may not be stretching as such but maybe stickey or gooey. I know this is usally consistant with old stretching belts but i have in the past found the belt to be fine is size but still gooey. In that case replace it and clean the turntable plate where the belt runs and also the brass speed adjuster, this sticky stuff builds up on both places and can cause all kinds of wierd faults.
Just a few h> > Most of the time, my Sony PS-LX430 turntable runs too slow. On the
I think you are getting confused about what constitutes a " direct drive " turntable. A directly driven turntable is one where the centre bearing of the platter is also the shaft / bearing of the motor - ie the motor *itself* runs at either 33 or 45 RPM, and is an integral part of the speed control servo loop. It usually employs a multi-magnet rotor, which is often part of the platter itself, and is driven by an electronically generated and controlled rotating field that is applied to the stator coils. This is not the case where a small DC motor with an internal governor, is fitted, such as has been described. These invariably run at a couple of thousand RPM, and drive the platter via a belt. The other drive scheme, now obsolete for many years, is idler drive, where a high speed motor with a stepped shaft, drives the inside rim of the platter, via a spring-loaded rubber jockey wheel.
I'm pretty sure that these Sonys use a belt-drive from a small DC motor, but I have a dim recollection of them having an external control board, with a difficult to obtain 4 pin regulator IC, which had a habit of failing. I could be completely wrong there, it's been a long time since I saw one, but there's definitely some bells ringing somewhere ...
It's probably worth the OP just checking the joints on the regulator, and any speed-set pots and selector switches, but I think it likely that he will be up for at least a replacement regulator IC, and probably motor as well, if they are still available. It may be possible to sub a cassette motor with an internal governor, but bear in mind that one of the dual speed ones would have to be used, which always use external speed-set pots, and it may be difficult to get the required shaft speeds and torque, to match the pulley size fitted to the original.
It usually employs a multi-magnet rotor, which is often part of the platter itself, and is driven by an electronically generated and controlled rotating field that is applied to the stator coils. This is not the case where a small DC motor with an internal governor, is fitted, such as has been described.
This is quite true indeed as i did not suggest anything about that i simply asked the question. It too has been awhile since i looked at one as well.
As for the reply from Mr Payne in the ass.
You sir are the reason why a lot of ppl simply read and do not reply to posts. It is with comments like yours that drive ppl away from these sites. I did not see your input either. So instead of adding remarks like that, why not use the quick wit you have displayed and vist the quick wit groups and save us all the from your unwanted BS comments
Try spraying the speed switch with deoxid 5 and working it back and forth a few times and if you can reach them, the speed pots. If this takes care of the speed drift, then set the pots for accurate speeds. Chuck
On Fri, 14 Jul 2006 09:13:13 GMT, "Arfa Daily" put finger to keyboard and composed:
There are a few service manuals here:
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The cheapies (LX-40/43/44) appear to use a cheap 2-speed DC motor and a belt drive. I don't see the LX-430, though.
A free service manual is available from this site:
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Sony PS-LX430 Service Manual (includes extraction from Instruction Manual (User Manual)) in English PS-LX430 / PS-LX430C / PS-LX431 / PS-LX431N / PS-LX433 9-952-171-11
BTW, I have obtained one manual from this site in the past. The site owner asks that you donate to a particular human rights organisation but will still allow you to download a manual if you have already donated to other charitable organisations of your choosing.
- Franc Zabkar
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Please remove one 'i' from my address when replying by email.
"Eiron" wrote in message news: snipped-for-privacy@individual.net...
This, however, is NOT your bog standard motor and jockey wheel drive. It is instead, a precision motor and specially made drive wheel assembly, fitted to a phono deck that costs 10,500 ( That's ten THOUSAND ) quid. I would expect to get a very superior drive system for that. I'm not sure that I can accept all the blurb that's published on this deck, in an effort to justify its ridiculous cost. I think most people, including those who profess to be able to hear the difference between interconnects, would struggle to hear the few dB extra 'quietness' in the drive system over a belt drive, that the makers claim. I notice that they do not quote any figures over a genuine direct drive system. As far as the claims about wow and flutter go, again, I would dispute that this can be genuinely 'heard' without the use of sophisticated test equipment, if comparing the 501 to a good quality belt or direct drive deck, with a heavy platter. The laws of physics dictate that due to the inertial mass of the platter, you simply can't make rapid changes to its rotational speed. It would be interesting to know what type of motor is actually used in the 501, and how exactly its apparent speed stability is achieved. There are people, I know, who will always claim that things like this are definitely better, and worth every penny of the price, but I rather suspect that many of them, are still combing e-Bay to find a bottle of snake oil to lube their tonearm bearings with ...
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