I'm wondering if anyone out there can help me. I have a customer with
a Universal Player piano (yeah, I know!) with symptoms I've never run
across before. The player works fine when pumped; in fact, I've never
experienced a tighter pump action, one or two pumps and it seems to run
forever! However, when using the electrical controller, the roll motor
works, the speed control is fine, and the vacuum motor sorta works.
The vacuum motor runs weakly, the pneumatics barely strike the piano
action only occasionally providing enough power to play a note.
However, somewhere between one-third and two-thirds of the way through
the roll, the vacuum motor gradually increases in speed and power and
the player works just fine. Equally maddening, this doesn't happen on
every roll! Sometimes the vacuum motor just continues weakly and never
increases power. And every time a new roll is started, or the old roll
is started over, the vacuum motor starts weakly.
This customer is 50 miles away (not too many player techs around here)
and I need to make the best use of my time. I'm planning on disconnecting
the motor from the controller and wiring the vacuum motor directly to
power to test the motor itself. I'll also take my shop motor along to
test it with the controller board. Other than that I don't know what
else to do other than checking the transformer output, etc., to see if
the voltages make sense.
The controller is the type with two sliding controls, one for the lights
and one for the motor. I suppose it's possible that the motor slide
control is intermittently whacko, but I have my doubts. Usually this
type of slide will 'open' or 'short' hard, leaving you with a totally
non-working unit or with smoke and charring! I've searched the Internet
and have made copies of the Universal Controller Board schematics from
John Tuttle's web site (thanks to John Omiatek) but I don't think this
is the same controller. I'll try to check that.
The I.D. tag on the player identifies this as a P1 model, S/N 3605.
The piano is S/N 746351, purchased sometime in the late 1970s or early
80s.
Thanks in advance for any help.
Bob Myers - Myers Piano Service
Cleveland, Ohio
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