SMC Jukebox

I have a SMC jukebox that will reject a record upon needle drop. I know it isn't mechanical because it will play through with the mechanism plug out of the amplifier, but I have no schematics (coming soon in the mail I hope!) to let me get further with this. I also know it's not the switch to the left of the arm, it measures open unless the arm is near the end of a record. I'd appreciate any tips or advice anybody has to give me.

Thanks, Don.

EDIT: I also repaired the amplifier and have verified that it is fully operational in another jukebox.

Hi Don,
If you have any schematics from the LPC- on up--that circuit is the same---
Try the following:
Unplug the the amp AC, make a selection. Allow it to begin playing and insert that plug. If the mech trips, at this point, check switch 1M3--must be open in play, or check the switch on the back of phono, or remote switch if used. It does not trip, , adjust switch 1M3 to open prior to 1M4 closing. Switch contact sets are counted from the bottom up--these are on the first set of switches, up top on the switch-plate. Ron Rich

It trips when I plug it in. I have a page that has the contacts and what they do, of course they're letters instead of numbers. Would MB be the equivalent of 1M3 and O the equivalent of 1M4? If so, they are as you said they should be.

Don,
If you are looking at a "100" selection, pin-bank style mech, adjustment procedure, it would be shown as the "MB and "V" contacts.
Try the following, after being sure the MB's are open in play--
Remove the mech/mute plug from the amp. Make a selection and allow it to play. At this point, determine if the trip relay in the amp is energized, or not. If NOT energized, plug the mute/trip connector back in, while watching the relay. If it energizes now, you have a short in the reject circuit. If it does NOT energize, but trips off anyway, the relay contacts are "shorted", within the amp. BTW--that relay is supposed to be "specially adjusted"--See my "Seeburg MicroLog Trouble Shooting guide" for info.

I've got a 160 select one for a LPC according to the pages. When plugging the cable in I can see the relay closing, and unplugging the mech cable has it opening. DId these have any "usual suspects" that would cause this more often than others? I'm digging throughall the pages I have for a schematic.

I believe it's the same on the LPC schematic--anyway, it's the "V" for sure, and the one directly below it.
If your relay is energizing when the mech is in play, and the MB is open, V is closed, that is telling you that one (or more) of the end record switches, is closed, or the wiring is "shorted"--somewhere--most likely near the volume control ( black and white wires).
Ron Rich

I'm back, "stuff" got in the way but I should be good now. So you said it's telling me that one of the reject switches are closed or there is a short in the wiring somewhere. I assume that unplugging the volume control gets rid of the rear switch, leaving me with the mechanism and the amplifier. The amp is proven good, and the tone arm switch is proven good, so that leaves me with the short somewhere in the mechanism or wiring correct? I have recently cleaned and degreased and relubed as detailed in your mechanism guide Ron, so now it's just finding the short.

Question, the trip coil is always hot and only trips when grounded right?

Hi Don,
Yes-sir, you are correct--
On SMC's only there is an added "Autoreject" board in the CPA switch box--you can pull the plug on that switch box, and the phono should still run (provided credits were established)--try that, as you may either have a shorted PCB, or switch in the switch box. Ron Rich

Ron, thank you very much for your help! You just saved me at least a few hours poking around on the mechanism! I'll have to get around to fixing that later, but for the time being will it harm anything running without the CPA?
Again, thank you Ron.

Hi Don,
No problem--glad I remembered ! ( You CAN, put a check in the mail ) Other than the fact that no one can use any of the switches contained therein, it can run "forever" as long as the contacts on that plug do not "short-out". Ron Rich