But when I put a record on to play, the tonearm sometimes moved forward and sometimes stopped and wouldn't move forward. So I played around with holding down the start and stop buttons. I found that if I pushed down hard, the arm would move quickly back and forth every time. But when I pushed down gently, sometimes the arm would move and sometimes not.
I think what may be happening is that the whole gear system is a little "sticky" so that the motor can drive them at high speed but not at low speed. I am going to take everything apart again, clean off all the old grease and lubricate every part of the gear system that moves the tonearm back and forth. I have a tube of "Super Lube" synthetic grease that I think will work really well to make everything run more smoothly, even at slow motor speeds. I'll report back here after I do that.
She's gettin' there......
Sleeping Beauty's gotta be exercised, microswitches, contacts and sensors all have to reawaken by contact cleaner and use (wearing away oxides)... etc... and then when it's all clean, electrical measurements and adjustments back to spec.
The <<>> Technics linear buttons are 2 step buttons, 1/2 press / depression advances / reverses at a slow rate, full press = fast rate. So perhaps the 1/2 press electrodes are dirty resulting in intermittent advance / reverse. I don't think they can be easily cleaned but seem to respond to repeated usage.
The intermittent movement while the tonearm is on an LP sounds like a dirty offset sensor and / or some control voltages out of spec.
I've pretty much tried to remove all of the old grease from the tonearm drive mechanism. There's more than enough on all the linear's I've come across and find the remaining light / thin coat of remaining grease after cleaning is enough supplemented with a modern lightweight Teflon based
lube on the tonearm guide rod.
flavio81 has an excellent suggestion, lifted from another SL-7 topic, and that is to use / hold the "Open" button when closing the dust cover and not letting it snap shut. The latches that hold the dust cover down are plastic and can / may break. This is why my SL-7 is in semi retirement, one of the cover latches broke
and I need a heavy book / weight to hold down the cover when playing LPs.
Fred and thinking hard on a latch solution as the dust cover is no longer available as a replacement part.....
Music is Everything....Except Predictable....WFUV Fan.