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View Full Version : Akai GX-280D Weak Solenoid - Got a Schematic?

gsauther
07-09-2007, 12:03 PM
I have a beloved Akai GX-280D reel to reel deck with a funky solenoid. The solenoid that holds the pinch roller in place fires, holds for about 1 second, and then releases.

Any ideas about where to look? A schematic would sure be helpful if anyone has one available. Anybody know where I could download one for free, or for a nominal price?

Thanks for you help in advance. Gary
macaltec
07-09-2007, 12:17 PM
Check out the info in this thread http://www.audiokarma.org/forums/showthread.php?t=109834
Welcome to AK too.
Fred Longworth
07-10-2007, 02:44 AM
I sincerely doubt that the solenoid is responsible. More likely, either the pinch roller arm assembly is sticky, or when the solenoid latches it trips a microswitch, which permits it to hold in latched mode -- but the microswitch has gone bad.

Fred Longworth
gsauther
07-10-2007, 10:13 AM
I sincerely doubt that the solenoid is responsible. More likely, either the pinch roller arm assembly is sticky, or when the solenoid latches it trips a microswitch, which permits it to hold in latched mode -- but the microswitch has gone bad.

Fred Longworth


Thanks for the help. This is a terrific forum. I will check into it.:thmbsp:
Strangeband
02-20-2008, 05:23 PM
And welcome to the broken Akai GX-280D club. Mine doesn't work and a fellow AKer a short distance from here has another broken one.
cbrworm
02-21-2008, 07:41 AM
I believe there is a separate circuit for the lower 'hold' voltage for the solenoids.

When it first engages it will pull it into place with ~100 Volts if I remember correctly, then after a delay it will switch to a different power circuit and hold it with about 30 volts.

The delay is created by a microswitch with a spring and some sort of damping - you could have a broken wire in the lower voltage path, or a bad microswitch. In my deck it is labelled QT Switch4. On my deck it is very straight forward - straight from the transformer (through a fuse possibly?) to the timed microswitch (QT-4) that switches between 30/100 volts into a full wave bridge and on to the play/ff switch relays. In this case if it is initially latching and then releasing I would think most of the circuit is good and you are just missing the 30 volts.


I also understand that the interboard connections are problematic on the 280's.