Lubricate the spindle?
Sony 2251 and/or 2250 owners thread
- Thread starter mackat
- Start date
stratokaster
Mental toss flycoon
It's probably not the spindle. PS-1800 is just like TTS-3000 - it has adjustment pots for both speeds.
Oh well, trying to rule-out cheap (read: free) fixes. 
stratokaster
Mental toss flycoon
I'm pretty sure adjusting the pots is not that expensive either 
Hope that does the trick.
willewampe
New Member
thanks! adjusting it through these pots was successful! yeah!!Hope that does the trick.
could it be the speed was incorrect because the tt is put on 240v although in germany we only have 230volts??
stratokaster
Mental toss flycoon
No, that's because the components go out of tolerance over time.
Well, I could just kick myself right now! From time to time, I turn on the turntables I haven’t been using recently, just to let them run for a few hours. I’ve done this with the 2251 a number of times, and never had a problem. Unfortunately, this time, I forgot to turn it off, and when I woke up (about 12 hours after I first turned it on), it was spinning at probably over 100 RPM. It’s unplugged and cooling off as I post this. The spindle and area close to it on the platter were pretty toasty, and a bit of oil had bubbled up from inside the motor. I’m not so concerned about the speed issue, I’m sure this turntable needed a recap a long time ago. I just hope it didn’t permanently damage the motor from hours of high-speed rotation.
Worst case, I’ll pick up another one someday. Ughhh
Worst case, I’ll pick up another one someday. Ughhh
Well, I just plugged it in again after it had time to cool off, and it’s currently holding proper speed at both 33 and 45 rpm (it was at 45 rpm when I left it on last night). I’m sure there are various components out of spec, as the speed does drift slightly faster after it being on for a while. I suspect that because of the amount of time it was left on, it started to overheat, which affected the speed circuitry severely. I’ll have to get it worked on one of these days, assuming the motor is still okay internally.
Anyone have good cartridge matches for the PUA-114? I've got a Shure V15 type II on there, considering either a new stylus or a new cart.
stevepaige
Active Member
Here is the table with the PUA-113, which is what is actually in the above pic.
Chula Vista-Sony 2251, PUA-113 and Stanton 680ee Cartridge - YouTube
Never used the Sony tonearm with my 2251. However, the SME 3009 Improved Type II, with Denon DL-103R (Soundsmith boron cantilever and NCL modification) is a match made in Heaven. There are very few tables I've heard over the years, which are better.
Hello dear community!
I am writing through an auto-translator, so don't judge strictly ...
Please help in repairing a critical malfunction of Sony - PS2500.
When you turn on any of the speeds (33 or 45), the disc begins to accelerate very quickly uncontrollably. I did not wait longer than 2 - 3 seconds - turned it off; very high speed !!!
I checked the electrolytic capacitors - everything is normal: capacity, leakage currents, ESR is normal. Or does it make sense to replace them?
Q6 is tested as good.
Motor windings: 50, 160 and 800 ohms.
I ask for advice on what to check first.
I posted the same message asking for help in troubleshooting in another forum thread.
Thanks in advance,
Lelik.
I am writing through an auto-translator, so don't judge strictly ...
Please help in repairing a critical malfunction of Sony - PS2500.
When you turn on any of the speeds (33 or 45), the disc begins to accelerate very quickly uncontrollably. I did not wait longer than 2 - 3 seconds - turned it off; very high speed !!!
I checked the electrolytic capacitors - everything is normal: capacity, leakage currents, ESR is normal. Or does it make sense to replace them?
Q6 is tested as good.
Motor windings: 50, 160 and 800 ohms.
I ask for advice on what to check first.
I posted the same message asking for help in troubleshooting in another forum thread.
Thanks in advance,
Lelik.
stratokaster
Mental toss flycoon
Check the motor's built in frequency generator (two violet wires). Check Q1, Q2, D1, D2 and associated circuitry. You'd need an oscilloscope to check the waveforms at various points. It's all described in the service manual.
stratokaster
Mental toss flycoon
In the service manual there is a list of test points and a list of waveforms that should be present at those test points. You can get the service manual here: https://www.vinylengine.com/library/sony/ps-2251.shtml
I studied the service manual. All clear.
My question is about the technical part (so to speak).
The problem is this:
- to check the waveforms, the motor must be started. In my situation, after the start, the motor starts to gain momentum very quickly. There is a threat that it may collapse.
My question is about the technical part (so to speak).
The problem is this:
- to check the waveforms, the motor must be started. In my situation, after the start, the motor starts to gain momentum very quickly. There is a threat that it may collapse.
stratokaster
Mental toss flycoon
Your problem is that the servo circuit isn't getting FG signal from the motor. The circuit "thinks" that the motor is too slow and tries to increase its speed until it reaches the runaway condition.
Start by rotating the motor by hand and checking that you get the sine wave feedback signal at the output of the motor's FG generator (two violet wires).
The fault is most likely either in the servo IC itself (Sony CX032B) or right before it - in the differential amplifier (Q1 & Q2) or the diode limiter (D1 & D2) or the passive components around them.
FWIW, you could try feeding the differential amplifier with a sine wave from a function generator for debugging purposes.
Start by rotating the motor by hand and checking that you get the sine wave feedback signal at the output of the motor's FG generator (two violet wires).
The fault is most likely either in the servo IC itself (Sony CX032B) or right before it - in the differential amplifier (Q1 & Q2) or the diode limiter (D1 & D2) or the passive components around them.
FWIW, you could try feeding the differential amplifier with a sine wave from a function generator for debugging purposes.
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