Hello there,
I restored a TD-150: replaced the plinth, redid the wiring, replaced capacitors, new tonearm and board, and new drive belt; along with clean-up, lubrication, etc. I also removed the mechanical parts and belt guide for the 33/45 switch, so it only spins at 33rpm. That's all I need for the music I play.
It's working very reliably, except that on start, the platter won't spin without an initial push—by that I mean that I have to put my finger on the record label and spin the record for a turn or two until it gets to the right speed. After that, no problem.
I haven't done any measurable speed tests, but the pitch of the music I hear matches the digital files I own.
I observed the motor pulley by turning the platter upside down (to keep the same weight) and I noticed that on start-up the pulley is "wiggling" back and forth (about 1mm) very fast. There is a faint clicking noise. If I nudge it out of this, the clicking noise is gone and the assembly runs absolutely quiet and smooth.
The same problem persists with the platter off, with the motor connected only to the sub-platter. If I disconnect the belt, the pulley rotates freely, but in random directions, each time I turn it off and back on.
Before I start buying replacement parts or doing non-reversible modifications, I wanted to hear someone's opinion on the possible cause:
Belt too tight? I think I read somewhere that most replacement belts are. How do I check that, and how do I loosen it up?
Old or damaged motor?
Too viscous oil? In a forum I read I can use a 75W-90 motor oil, and that's what I'm using, but elsewhere I read I should use a low-viscosity oil to reduce friction.
Some electrical issue? The new caps are PP with the same values as the old (likely original) ones. I rewired the components according to the original instructions for 120V mains (I'm in the USA). I connected the hot wire to the motor blue wire (polarity is not indicated, so I guess it doesn't matter).
Anything else?
Thanks,
gm
I restored a TD-150: replaced the plinth, redid the wiring, replaced capacitors, new tonearm and board, and new drive belt; along with clean-up, lubrication, etc. I also removed the mechanical parts and belt guide for the 33/45 switch, so it only spins at 33rpm. That's all I need for the music I play.
It's working very reliably, except that on start, the platter won't spin without an initial push—by that I mean that I have to put my finger on the record label and spin the record for a turn or two until it gets to the right speed. After that, no problem.
I haven't done any measurable speed tests, but the pitch of the music I hear matches the digital files I own.
I observed the motor pulley by turning the platter upside down (to keep the same weight) and I noticed that on start-up the pulley is "wiggling" back and forth (about 1mm) very fast. There is a faint clicking noise. If I nudge it out of this, the clicking noise is gone and the assembly runs absolutely quiet and smooth.
The same problem persists with the platter off, with the motor connected only to the sub-platter. If I disconnect the belt, the pulley rotates freely, but in random directions, each time I turn it off and back on.
Before I start buying replacement parts or doing non-reversible modifications, I wanted to hear someone's opinion on the possible cause:
Belt too tight? I think I read somewhere that most replacement belts are. How do I check that, and how do I loosen it up?
Old or damaged motor?
Too viscous oil? In a forum I read I can use a 75W-90 motor oil, and that's what I'm using, but elsewhere I read I should use a low-viscosity oil to reduce friction.
Some electrical issue? The new caps are PP with the same values as the old (likely original) ones. I rewired the components according to the original instructions for 120V mains (I'm in the USA). I connected the hot wire to the motor blue wire (polarity is not indicated, so I guess it doesn't matter).
Anything else?
Thanks,
gm
It seems like motor lacks starting torque.
Assumig start/run 0,33uF capacitor is ok, possible cause is one of the windings is broken/disconnected. Check both of them for continuity.
Assumig start/run 0,33uF capacitor is ok, possible cause is one of the windings is broken/disconnected. Check both of them for continuity.
I resolved this. It turned out to be a bad connection with the .33 cap. It was on a screw terminal and has short leads, that didn't reach far enough into the terminal. I soldered the connections now instead.
Thanks for asking me to check the capacitors! They are new so I didn't think about checking them, but that also led me to find out about the connection.
The platter starts and runs as it should now.
Thanks for asking me to check the capacitors! They are new so I didn't think about checking them, but that also led me to find out about the connection.
The platter starts and runs as it should now.