This is a compact design to I guess transfer the vinyl into MP3 format.
Complaint was when the arm was moved the tt dont spin, confirmed that as
theres a leaf switch to sense arm movement,
and its fed to a main pcb with all the IC's that I guess handle all the
stuff. The switch is ok, and I remember seeing 14V or so on the motor pins
frm the PCB, so I figured perhaps theres anough current to spin the motor and
focused on testing the motor.
Manufacturer does not supply the mainboard that feeds the motor but
the motor can be taken apart and after I opened it and
disconnected the small pcb fron the motor terminals and apply power
directly, it spins w 12v. theres a small electrolytic cap on the pcb 25V / 22uF and an
AN6652 4 pin T0-220 type case IC that I guess is some kind of speed control
circuitry.
The drive Motor is an EG-530-SD-3F, main board is stamped K-13007.
Gonna check the cap, but after searching this IC and its
applications with the motor, I see its popular and some drawings show how its used to regulate the 78,33
and 45 rpm speeds.
This drawing looks pretty much what I see in there:
https://tectronelectronics.eu/images/thumbnails/465/465/detailed/31/eg530.jpg
I have replaced the IC and the cap, but the motor still does not turn. The main pcb
is proprietary and cant be purchased, and I think it is giving the op-amp IC a reference signal.
Is there a way to bypass that signal or fool the IC to believing its on to test it out?
Photo showing the motor pcb :
http://www.mediafire.com/view/s79blgku1503mtg/HPIM0643.JPG/file
Photo of motor under test:
http://www.mediafire.com/view/thhgvcwac8al7gu/HPIM0635.jpg/file
I drew a diagram showing the sub-pcb with the potentiometer mounted on it which interfaces with 2 connectors that
go to the main pcb and the motor. All wires on the motor have 12V except brown. I believe brown is the ground.
If you move the tone arm all the way so its at the end of a record, the leaf opens
and no wires have power. I concluded that this is the auto stop, because when you turn the
auto-stop sw off, the power is always on the motor.
Customer had said to get the table turning, you have to move the arm off the resting pad, but I am not so sure now that is correct...
as the leaf is for auto stop.
With 12V on all the wires, Im told the motor must turn. The IC is a new one, and the electrolytic cap on the motor pcb is new.
All I can think is there is not enough current maybe. How much current should a motor like this draw? How could I test this IC to see if its not bad from stock?
0
Datasheet of the motor driver IC which is made by Panasonic can be found there: http://www.alldatasheet.com/datasheet-pdf/pdf/PANASONIC/AN6652.html. You can also find it attached. There is some example how to use the circuit and the usual data in that datasheet. Current drawn by the motor should be in the range of maybe 50..100mA. If your motor will draw more than that I would suggest to clean the motor bearings and get some new oil lubrication there, it will be stuck by hardened oil stain.
1
I made a new drawing of the motor pcb with photos of that board plus the small connector board.
The yellow wire to the control pin of the IC came apart after I stripped it, so after fixing that and testing again,
I stil had the same issue.
Out of curiosity I jumpered the control pin to gnd, and the motor began to finally run, and the speed switch correctly sets the slow, med and fast speeds,
however I have no way to know if they are too high or slow. With that jumper, the leaf switch that normally closes when you move the tone arm off the resting clip
to apply power to the motor pcb no longer turns that power off, its constantly there which is odd.
How can that jumper to the control pin be making it seem to now work? The IC is a new one, but I guess its always possible its bad, however the original one didnt let the motor run as well.
0