Hello everyone! Does anyone know where I can find a replacement motor for the Sony TCM-77V? I believe the TCM-77 uses the same one. I’m also open to alternative motors that would work, even if they’re not the original part. According to the service manual, the motor details are: M901 - 1-541-716-11 (NBL-122) Here’s a picture: And the pinout from the service manual: I measured the voltage between GND and VCC, and I’m getting 3.2V, but the motor isn’t running. So I’m guessing it needs to be replaced. Any help would be greatly appreciated! Thanks!
Does the motor pulley rotate freely ? Apart from Vcc, you need the drive signals for the 3 phases U, V, W. It's a 3-phase brushless motor, not DC motor. So just because you have Vcc and motor does not run doesn't necessarily mean the motor is faulty.
Yes, it does rotate freely when I move it with my fingers. Measuring the voltage on U, V, and W against GND gives me 3.2V. Also I've desoldered the motor and measured resistance between GND and any of the other pins and it reads open circuit. I would expect to get a some resistance reading right?
Yes, you should have a low resistance between U, V, W and ground, something like 1.5Ω. But this is assuming those pads go directly to the coils, which I'm not sure is the case here. Given the additional Vcc pin, it's possible there's some electronic circuit inside the motor. This particular motor design I haven't seen before and did open many similar looking motors. The DC voltages at U, V, W will be similar to Vcc (a bit lower usually). But for proper insight you need to see the waveform (and need oscilloscope for that). At first glance it would indeed look like a faulty motor, but wouldn't be quick to draw the conclusion. Are there electrolytic capacitors in this unit ? Would rather suspect capacitors than a faulty motor.
Yes, this model does have some electrolytic capacitors, but I’ve already replaced them—some had already leaked, and I had to endure that lovely fishy smell while desoldering. I was hoping to find a replacement motor to confirm if that’s the issue, but it doesn’t seem like an easy task. I guess I’d need to find another TCM-77 and salvage the motor from there.
