Hi Orzric, Thanks for your reply. The drive belt is set for 60HZ on the smaller diameter motor pulley. Also the Capstan Motor is a hysteresis synchronous type, it operates at the main power supply frequency. I checked the service manual and I can not find any control to fine tune the capstan speed. If you have any other ideas let me know. TanksI ran into this same problem with my TEAC A-4300 SX. Is this a belt driven unit ?, If so, is there a double pulley on the motor ? One may be for 50hz and the other for 60hz operation. I am not familiar with Pioneer designs but that is how my TEAC A4300 SX works.
Hi dr*audio. I can not find any variable speed control, with a switch in it for this unit.The capstan motor is a hysteresis synchronous type, which operates at the main power supply frequency. The speed does require a fine adjustment. It is enough for a person to notice the pitch is wrong. The problem is how to perform this fine speed adjustment. Thanks for the advice, and any help is much appreciated. ThanksI think this deck has a variable speed control, with a switch in it. If so, the first thing to do is clean the switch and control. if that doesn't work, there should be an adjustment on the capstan motor speed control board.
My Rt-1020L is playing a little too fast at 7 1/2ips. Any suggestions regarding the fix for this problem would be welcome. I have the service manual for this unit. It is a 60/50HZ unit. The ac line voltage is set at 120 VAC. Line frequency at 60HZ. Thanks for your help.
Thanks for the info, you are right, the unit is ruuning a bit faster than it should at 7 1/2ips. I found an adjustment pot on the capstan servo board, but that concerns more torque adjustment, and I do not believe that will cure the problem. The unit is definetely running a bit faster than it should at 7 1/2ipsI though he said it was running to fast so sticky heads is not the problem.
Thanks dr*audio. You are right about the pulley diamenter. I will try to find a machine shop in my are so that they can turn down the pulley. Another solution is to find the original slightly smaller pulley for this unit. Question is... do you know where I can buy one of these pulleys? I know Pioneer Parts is out of stock. I have to find a machine shop in my area, I wish I knew how much to take off this pulley. Thank you very much for the very wise advice.If you mean the pulley on the motor shaft, no, larger diameter means faster speed. A larger pulley on the motor makes the flywheel turn further with each rotation. So you probably have the slightly larger pulley and need a smaller one, or you could get the pulley turned down by a machine shop. You could ask them to take a small amount off at a time and then you could try it.
Thanks jblmar, I think you suggestion is very well taken and it makes a lot of sense. Let me think what I will decide to do with this unit in the next two days, I will let you know. Your contributions to this Forum are most welcomed.You need to measure the Pinch Roller tension if the speed is fast or slow. For this measurement, you need the proper spring scale.
I wouldn't touch any adjustments before taking all tension measurements. Don't forget all tension points are interrelated.
Ron
Unfortunately, a line locked motor such as this has no way to adjust the speed. Have you checked it with a speed calibration tape and a frequency counter? If so, the only things you can look at are the capstan belt, lubricating the capstan motor bearings, cleaning and lubricating the capstan bearings, including the rear bearing, and checking the play on the rear bearing (not enough play will create drag.)
Also check the tension on the supply reel. If it's too high, it will slow the deck down.
Check that the tape isn't sticking to the heads. Ampex back coated tapes will do this. Eventually they can stop the transport dead. Make sure the heads don't have any sticky residue on them. This can cause a good tape to slow down.
If you have a wow and flutter meter you can check for wow and flutter. A bad capstan bearing would show up with high wow or flutter.
Thanks jblmar, I think you suggestion is very well taken and it makes a lot of sense. Let me think what I will decide to do with this unit in the next two days, I will let you know. Your contributions to this Forum are most welcomed.
Hi jblmar, I did check the speed accuracy of the unit at 7 1/2 ips with my Teac Test tape with the 3KHZ tone. Result, the unit is definetely running faster, I got about 3.215KHZ average using my Fluke Frequency counter. I also checked the Take-up reel torque Resistor tap, intact from the factory, it has never been moved, the same goes to the capstan solenoid assembly.( no screws have been turned, still have the original factory laquer ion them. I did apply pressure to the pinch roller by placing my finger on the pinch roller itself, and I could get the speed frequency to go to 3.02KHZ, withing the tolerance. Should I move the solenoid in and out, or should I try to do some trimming with the pulley and/or flywheel. Thanks for your help. We will conquer this situation. Yes the RT-1020L is well built and I love its sound quality. Thanks again. When I got the right speed accuracy, in the pinch roller test, the tape started squealing.The 1020L is a very well built machine. Worth getting up to speed.
Ron