DC motors and outboard power supplies...


For those of you with analog rigs that utilize a DC motor and outboard power supply....I'm wondering:

1. How often do you check to see if the platter is at correct speed?

2. How often do you have to fine tune the speed adjustment?

3. Once fine tuned, does it stay throughout the listening session, or do you need to make adjustments throughout?

4. Would you be willing to comment on which table you are using?

Thank you for your comments.
no_regrets
Hi Lewm,

Thank you for your response. My table is a Linn LP12 that was modified by Pink Triangle with a Pink Link DC Battery Power Supply. I take excellent care of the bearing assembly and really do not feel it is the cause of the problem. The inner platter and pulleys have been cleaned, the belt has been replaced with a brand new one so I don't think that is it either. What is confusing to me is that there are times when I can listen for up to eight hours strait with no problems. Other times it occurs within the first hour or two. I think that your suggestion about measuring the output of the supply is a great idea and should tell me if the problem is the supply or the motor. I will try to do that tomorrow. Thank you for that suggestion.

Hello Raul,

Believe me, I have done much research and have participated on many of the forums that Linn and Pink Triangle owners frequent. I have had many good suggestions but to no avail. I know I will most likely have to buy a new motor and power supply but I sure would love to try and fix what I have first because when it is running correctly, I do love the way it plays records.
Since Adjust+ is available, I heard from lot of users, that their - expensive - Turntables are drifting. That's more common than most of us think.

I am using
a, Basis Debut with Walker controller
b, Micro Seiki 5000

. How often do you check to see if the platter is at correct speed?

for both at the beginning but then I stopped that

. How often do you have to fine tune the speed adjustment?
a, never
b, never

. Once fine tuned, does it stay throughout the listening session, or do you need to make adjustments throughout?

a, stable
b, stable

. Would you be willing to comment on which table you are using?. How often do you check to see if the platter is at correct speed?

maybe 1x in 14 days
Dear No regrets: Normaly a speed TT has to be fix ( by design ) on 33/45rpm on the electronic circuit in the PS and normaly too this could be through a " pot " ( variable )that is the part that makes that job and for check about you need the diagram or a technician if you can't do it. I don't know how this works in your TT but you can contact to Linn and Pink Triangle and ask about.

Regards and enjoy the music.
Raul.
Syntax, thank you for sharing your experiences with me.

Raul, the people at Linn are of no help to me because the motor and powersupply are not from Linn. I have talked with the people of Pink Triangle who is now known as the Funk Firm. They no longer have schematics for this supply nor parts or replacement motors. I have even reached out to the designer of the supply who frequents a different forum, but to no avail as of yet. My supply does have variable pots to fine tune the speeds for 33 and 45. I can get the table to spin correctly, but then for no reason at all it justs slows way down. You never know when its going to happen. That's why I think it may be a regulator chip or capacitor going bad. I am going to try measuring the output of the supply today and see if I can in fact isolate the problem to the supply as lewm had suggested.

Thank you,
No Regrets
Dear No regrets: Ok, check what Lew suggest.

+++++ " My supply does have variable pots to fine tune the speeds for 33 and 45. I can get the table to spin correctly, but then for no reason at all it justs slows way down. " +++++

I don't know which kind of pots your TT has but from what are my experiences about and taking in ount what you posted: +++ but then for no reason at all it justs slows way down... ++++, maybe there is something wrong there because that kind a problem is a sign that a pot could be going out of specs and with the working time in the future that problem could be worst.

Btw, have you the trouble in both speeds?, if yes then I think that maybe is not a pot because it is almost imposible that both suffer a damage at the same time.

Now, for any one could to have a precise diagnosis it is desirable that the check-up on your TT have to do it when the failure is present.

I can't say nothing more except: good luck.

Regards and enjoy the music.
Raul.