Seeburg STD3 "Scans Twice" Problem

So, I was listening to my Sunstar the other day when all of a sudden
it stopped tripping at my selections.

I've had the "scans twice" problem before and I've always been able to
fix it. First it was bad 27VDC and another time it was a dirty detent
timing switch. This time, though, I am having trouble figuring out
and maybe someone can help point me in the right direction.

I have Tony Miller's Black and Gray Boxes book (a very good book as
well as invaluable, by the way -- helped me correct problems I was
having with the boxes as well as my previous "scans twice" problems).
So, I have been following his troubleshooting directions for this
particular problem. The 27 and 13 VDC voltages look good. On the
Read Load terminal, I get ~115VDC. Following his troubleshooting
method, I've narrowed down the problem to the trip section. The weird
thing is this -- I plug the Sunstar in and measure ~115VDC on Read
Load. I put the mech into scan, I hear the trip relay on the DCC
activate and Read Load drops down to 4-5VDC and never comes back up to
~115VDC. I checked the detent timing switch and it was good. I
checked 2M1 and 3M1 -- 2M1 was dirty (cleaned it and verified it was
working) and 3M1 was good. I am still having the problem, though.

What's even more weird is when I hook up an analog multimeter up to
ground and Read Load, and I set the meter to 10V, I see the needle
wiggle, as if the detent timing switch was doing it's thing, just
moving between 4V to 5V instead of 60V to 125V. When I unplug and
plug the Sunstar back in, Read Load goes back to ~115VDC.

Any ideas? Thanks...

Tony

On Oct 8, 9:36*pm, Tony wrote:
So, I was listening to my Sunstar the other day when all of a sudden
it stopped tripping at my selections.

I've had the "scans twice" problem before and I've always been able to
fix it. *First it was bad 27VDC and another time it was a dirty detent
timing switch. *This time, though, I am having trouble figuring out
and maybe someone can help point me in the right direction.

I have Tony Miller's Black and Gray Boxes book (a very good book as
well as invaluable, by the way -- helped me correct problems I was
having with the boxes as well as my previous "scans twice" problems).
So, I have been following his troubleshooting directions for this
particular problem. *The 27 and 13 VDC voltages look good. *On the
Read Load terminal, I get ~115VDC. *Following his troubleshooting
method, I've narrowed down the problem to the trip section. *The weird
thing is this -- I plug the Sunstar in and measure ~115VDC on Read
Load. *I put the mech into scan, I hear the trip relay on the DCC
activate and Read Load drops down to 4-5VDC and never comes back up to
~115VDC. *I checked the detent timing switch and it was good. *I
checked 2M1 and 3M1 -- 2M1 was dirty (cleaned it and verified it was
working) and 3M1 was good. *I am still having the problem, though.

What's even more weird is when I hook up an analog multimeter up to
ground and Read Load, and I set the meter to 10V, I see the needle
wiggle, as if the detent timing switch was doing it's thing, just
moving between 4V to 5V instead of 60V to 125V. *When I unplug and
plug the Sunstar back in, Read Load goes back to ~115VDC.

Any ideas? *Thanks...

Tony
POWER UP MACHINE=PUT DC VOLTAGE METERS CLIP LEAD TO THE RIGHT SIDE OF
DETENT SWITCH. LOOKING AT THE PARTS IN FRONT OF KEY BOARD.
THE VOLTAGE SHOULD CHANGE WHEN ROTATING THE MOTOR DRIVE SHAFT IN THE
SCAN POSITION,= AND MAKING THE MOTOR SCAN ONE INCH, MOVEMENT, ON THE
RACK, WILL CHANGE THE DC VOLTAGE READING ON THE METER, 400 VOLTS PLUS,
TO 4 TO 5 VOLTS. MOVE SOME MORE, 400 VOLTS TO ZERO. WHAT HAPPENS????
LOOK AT THE PRINT, I THINK IT SHOULD HAVE A LARGER VOLTAGE THAN 125
VOLTS.

Hi Dr. Fix,

Thanks for the suggestion. The issue might not be in the detent
switch. When I manually put the mech into scan, the trip relay (on
the DCC) energizes about a second later. In fact, the trip relay
stays energized until I power off the jukebox. It's strange because I
don't know why the trip relay is energizing even though I didn't
select a record. I would expect the trip solenoid to fire when the
trip relay energizes, but it doesn't. I can manually trip the mech so
it plays a record and the reject trip works to place the record back
in the magazine and put the mech into scan.

Tony