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Couple of questions about Orthophonic machines; first, is it possible to adjust the sensitivity of the auto shutoff mechanism? My copy of 'Low Down Rhythm' was pressed off center so it naturally trips the mechanism before the end of the record, but I have a few other records that really aren't that much off center and it's tripping before the end all the time. On almost all other records in my collection it doesn't do this, but it seems that the slightest bit off-center and it trips. Any ideas on this? My turntable isn't damaged nor do I have a bent center shaft - like I said it works fine with almost all other records. Low Down Rhythm is REALLY off-center; others aren't that bad but it still trips on those.

Also, does anyone know the size and thread for the limiting screw on the reproducer? I thought I had an extra in my shop but can't locate it.

Thanks!

Try a little grease on the teeth of the shutoff section, if that doesn't work, you can loosen the spring that puts tension on the teeth a tad. I've had good luck with both things but a really off center disc isn't going to play without shutting off unless you disengage it just when you play that particular disc.

Hope this helps,
Sean

My trip mechanism was the opposite recently because of a WAYYY loosened and unscrewed tonearm trip rod - thus it was too INsensitive, records began to simply not trip, period. Tightened, fixed.

Come to think of it, maybe you could add some *slight* play to your tonearm trip rod.
A smidge of looseness would allow greater lateral needle movement before it would trip. Perhaps some experimenting with the adjustment nuts on the rod, if this slight looseness could be set to be permanent. (Once mine came loose it just ended up unscrewing itself more and more.) Hmmm, or adding some very cushy soft material where the rod mounts to the tonearm, and not tightening it real hard, so has just a tiny bit more give at the trip fork.

OR - maybe some adj. or mod to the fork that the rod sits in, so that it doesn't completely close snuggly around the end of the rod but instead has a very slight amount of play. Not the most brilliant or correct suggestions probably, but hey I'm an 'if it works, it works' lazy dope. Good luck. : )

Mark

My trip mechanism was the opposite recently because of a WAYYY loosened and unscrewed tonearm trip rod - thus it was too INsensitive, records began to simply not trip, period. Tightened, fixed.

Maybe you could add some *slight* play to your tonearm trip rod, that would allow greater lateral needle movement before it would trip. Perhaps some experimenting with the adjustment nuts on the rod, if this slight looseness could be set to be permanent. (Once mine came loose it just ended up unscrewing itself more and more.) Hmmm, or adding some very cushy soft material where the rod mounts to the tonearm, and not tightening it real hard, so has just a tiny bit more give at the trip fork.

OR - maybe some adj. or mod to the fork that the rod sits in, so that it doesn't completely close snuggly around the end of the rod but instead has a very slight amount of play. Not the most brilliant or correct suggestions probably, but hey I'm an 'if it works, it works' lazy dope. Good luck. : )

Mark

I think I've finally solved the problem using all of your suggestions. I did grease the ratchet and the left arm of the fork was very tight so I got that lubed. Then I remembered that after rebuilding the soundbox, I also checked the entire tonearm and readjusted the U-tube swivel joint (it was loose and shouldn't be) which was providing extra 'play'. I did end up loosening the trip rod as well and now it's not hypersensitive. Going for the completely airtight sound path and doing so has brought up these other issues. Machine sounds really good now. Thanks for helping out.