Garrard Zero-100 speed control problem


My Garrard Zero-100 International idler wheel turntable won't slow down to proper speed. The Synchro-Lab motor in inscribed with the usual international blessings for 120 V/60Hz and 240V/50Hz, and the power cord inputs have little copper wire jumpers (what used to pass for a fuse in Britain) with guidance diagrams -- hence the International designation. Everything worked fine in England where I acquired it, but now that I have finally gotten around to unpacking it and coverting it for North American use, it is playing too fast.

With one neglible exception, everything is still original on this unit, including the magnificent plastic-&-cardboard plinth. The only change I have made is to attach the 60Hz strobe pattern donut to the underside of the platter. This paper donut sticker originally came with the unit, and was given to me by the original owner when he gave me the turntable. It just goes over the original 50Hz strobe donut sticker already on the underside of the platter.

I was about ready to start the tweaking and new plinth building process, but I did not expect to encounter problems with the speed after moving the voltage jumpers (fuses) to their correct positions. I have checked underneath to make sure the minor speed control adjustment is able to travel as far as it physically can, and it is functioning as designed. But even with it set as low as it can go, the speed is too fast, with both 33.3 and 45 rpm settings.

My suspicion is that while this International version only requires a fuse re-positioning to accomodate voltage changes and a change to the pattern for the strobe images, it requires a different wheel somewhere in the drive system to overcome the power supply cycle difference. Maybe this came with the unit when new, like the strobe pattern replacement donut, but was forgotten about by the time the original owner gave it to me decades later.

If this is actually the case, which wheel needs replacing? Do I need a smaller idler disk, or do I need a bigger version of the wheel attached to the motor shaft (the wheel which actually spins the idler disk which is contact with the platter)? Is either one of these easily available? I am not relishing the thought of either grinding down the idler wheel or putting tape on the outside of the motor spindle wheel pulley.

I confess that I have not yet actually measured the voltage inside to verify that it is indeed now 120V, so it is possible that maybe something is goofy with these wire jumper fuses. They are very short lengths with each end looped to fit over one of the four terminals available. When configured for 240V, the two jumpers BOTH sat on terminals 2 and 3. For 120V, the diagrams on the housing indicate that terminals 1 and 2 be joined together, and then 3 and 4 be joined together. I had thought that the different arrangements were only affecting whether the circuit was a parallel or series flow, but maybe there is more going on. Maybe I need TWO fuses on each leg of the 120V arrangement, since there were two on the one leg in the 240V configuration. I guess I could just wrap some more wire around the terminals and see...

I am open to all pearls of wisdom.

-BS


brett44
The Garrard Zero-100 is capable of excellent results when mounted in a solid plinth: I know, I've done it and lived with it, though I subsequently sold it. I'm not sure whether it it the motor spindle which is machined differently or the wheel. There are several sites which sell idler wheel replacements or even manufacture them, you could start by contacting www.turntablebasics.com, and also Technical & General in England. But the fact is that these particular Garrards are considered valueless by "the Man", and so I think it would actually be cheaper to bid on one on ebay, where they show up quite frequently, and use it for spare parts. Good Luck, this thing really boogies: I sold mine to an acid jazz freak who was happy as a clam (though it's difficult to imagine a happy clam)...
What you really need to do is raise the dust cover and put a new turntable under it.

The Garrard was a fine turntable but I was still in High school.
Hi

This is purely a cycles per second problem - the speed needs to reduce so you will need a smaller motor pulley. The decks were supplied with two pulleys - the alternate frequency one packed in a plastic bag, easy to lose/discard. Turntable Basics may help.

Afaik the copper links are just that, not fuses unless they have some rating stamped on them like car fuses. The coils are wired parallel for 120v and series for 240v.

hth

Regards
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