Hi
I have a Sony PS11 Turntable , the Problem is the platter will not start on its own, it needs a nudge then it is ok .
Anyone got any ideas has to what the problem could be, I was thinking maybe a Capacitor has gone bad ! .
cheers
Spike
I have a Sony PS11 Turntable , the Problem is the platter will not start on its own, it needs a nudge then it is ok .
Anyone got any ideas has to what the problem could be, I was thinking maybe a Capacitor has gone bad ! .
cheers
Spike
Does it spin freely on its own ?
Its a DC servo motor controlled deck , you move the arm above the record and it starts so it could be a problem with a photo diode ( if fitted ) , I have not seen the schematic for it and I presume the deck will not have the old fashioned mechanical start but an electronic start.
Seems there is a speed adjuster and selector that needs contact cleaner according to one owner.
Its a DC servo motor controlled deck , you move the arm above the record and it starts so it could be a problem with a photo diode ( if fitted ) , I have not seen the schematic for it and I presume the deck will not have the old fashioned mechanical start but an electronic start.
Seems there is a speed adjuster and selector that needs contact cleaner according to one owner.
Hi
Thanks for your reply, yes it does spin freely, am attaching the Service Manual for you to look at .
cheers
Spike
Thanks for your reply, yes it does spin freely, am attaching the Service Manual for you to look at .
cheers
Spike
Thanks for the schematic , check the offset adjustment ( RV4/5 ) to the drive amps ( IC3/4 ) to make sure the coils are equally balanced , the same with RV2/3 .
Also (as I said ) the two speed switch use contact cleaner also change the capacitor between the buffer amp and DC amp .
I was wrong I see it still uses the old fashioned mechanical tone arm movement control , I was thinking more of the 70,s/80.s designs .
Also (as I said ) the two speed switch use contact cleaner also change the capacitor between the buffer amp and DC amp .
I was wrong I see it still uses the old fashioned mechanical tone arm movement control , I was thinking more of the 70,s/80.s designs .
"Needs a nudge" often indicates that one phase is not being driven properly or at all. Occasionally you do see the odd driver opamp dead (if you do need one - this one is a plain LM324), or a dead output transistor. (One could also kill the other, e.g. if output transistor beta has taken a nosedive.) Offset is definitely worth checking as suggested, could be a simple dirty pot.
OP, do you have a scope? That would come in very handy.
It seems a pretty crude circuit if I dare say so - with the opamp being misused as a comparator and a Class B (well, actually C) output stage, coil driving isn't exactly what you would call sinusoidal. This may be intentional to avoid dead spots (there's a reason why fancier designs use 3-phase drive instead of just 2-phase), as well as reduce output transistor power dissipation, but would also require a fairly heavy platter to keep the FM spectrum sufficiently clean.
OP, do you have a scope? That would come in very handy.
It seems a pretty crude circuit if I dare say so - with the opamp being misused as a comparator and a Class B (well, actually C) output stage, coil driving isn't exactly what you would call sinusoidal. This may be intentional to avoid dead spots (there's a reason why fancier designs use 3-phase drive instead of just 2-phase), as well as reduce output transistor power dissipation, but would also require a fairly heavy platter to keep the FM spectrum sufficiently clean.
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Hi Guys
Thanks for all your feedback, it seems to be working ok , but the sound output is very weak! .
cheers
Spike
Thanks for all your feedback, it seems to be working ok , but the sound output is very weak! .
cheers
Spike
Are you still using the ceramic cartridge , it requires a special input impedance ?
If so there is a conversion to a MM cartridge input for ceramic although most ceramic cartridges are held in with a clip not bolts.
If so there is a conversion to a MM cartridge input for ceramic although most ceramic cartridges are held in with a clip not bolts.
Hi Duncan
It seems to be starting now ok, I adjusted the " Speed detecting Head" as per page 8 of the manual ok, cleaned some contacts etc .
But am having problems with setting the values for "All" the measurements on page 11 of the manual, the voltmeter readings are just fluctuating ie "Motor Gain Adjustment" Setting RV2 and RV3 the meter is reading from OL to 3.26 , 2.56,1.96 it just keeps fluctuating up and down those readings.
For the "Offset Adjustment" RV4 and RV5 it is fluctuating between 1.076,0.966,1.167 etc .
Cheers
Spike
Turntable sound problem,
Hi
Not sure what type the cartridge is, will attach pics .
Spike
Hi
Not sure what type the cartridge is, will attach pics .
Spike
Attachments
That's a magnetic, MM cartridge.
Labeled under several brand names, it's an ok cartridge for people that aren't too fussy.
Labeled under several brand names, it's an ok cartridge for people that aren't too fussy.
The company owning the brand (s) is now under a spot of bother and "indi products" is now supplying the Goldring range which used to be a UK owned /manufactured brand for lower end cartridges which I would class as "mediocre " .
I suspect the company mentioned has a connection to India.
I suspect the company mentioned has a connection to India.
Turntable Problems
Hi Duncan
Has I have just put on here , the sound is now ok , still have the problem with the RV settings though has mentioned earlier (post #8 to you ) any thoughts on that, just that to sort then I will be a happy man ! .
cheers
Spike
Hi Duncan
Has I have just put on here , the sound is now ok , still have the problem with the RV settings though has mentioned earlier (post #8 to you ) any thoughts on that, just that to sort then I will be a happy man ! .
cheers
Spike
