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That's such a useful yet not so obvious tip. Thank you sir!Loud Ticking Quartz Alarm Clock Repair
This describes a quartz alarm clock movement repair that is posted here to avoid losing it in the Clock Repair forum. Several YouTube videos to quiet a noisy quartz clock had inappropriate information such as using petroleum oil on plastic, taking action not needed such as oiling more parts than needed or installing a new conventional or a sweep movement.
The high quality clock, a Sharp Model SPC126 has a large 4-3/8" dia. white face with black hands for good visiblilty, an ascending volume and frequency four stage alarm and a snooze feature, all to make it worth repairing. The clock had an annoyingly loud tick audible for more than 10 feet.
Opening the clock case revealed the proprietary movement's enclosure. Removing the enclosure cover permitted lubricating the armature and first gearwheel plastic pivots with a tiny bit of silicone oil. After assembly the movement was nearly inaudible at a very close distance.
This is addressed to both sections of your post.That's such a useful yet not so obvious tip. Thank you sir!
Hello Les. How did you get on? I am waiting to hear! What an interesting movement. It looks to me as if the there is no rack to count the strikes but I do see a rotary switch with increasing lengths of printed contact. That's very likely to be the equivalent of a mechanical counting wheel with detents that counts out the number of strikes. When it runs and the contact falls off the edge it should stop. The switch that sets it off needs to be found. It will likely be on the minute shaft and operated by a cam. I'll bet if that is so that its in permanent contact making it run all the time.So I have a few new pictures as I progress, I see nothing that causes this malfunction! number 3 front Plate and hour gear, 4 is the time movement 5 flip side of time movement. Since things seem sticky electric cleaner and then clock oil on pivots?
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I like to call it an electronic balance because it has a (solid state) transistor but is NOT a quartz. Nor is it an "electric" balance. Its a resonant motor in the sense that it provides the power to drive the train and pointers but unlike a normal mechanical balance that absorbs power - this one redistributes the power it gets from the battery in very precise steps to the train. Really novel, (in its time), and can be uncannily accurate too. It seems to demonstrate to me that if the impulses are of consistent weight, isochronous action will be much better. No jewels; often a nylon train; clumsy but fast balance, yet accurate. I'd go further and conjecture that if the power level from the battery was held constant (not seen one that has a regulator), the performance would be outstanding and get very close to a quartz - positional errors excepted. All IMHO of course gentlemen. BerryGRe: The best quartz (fake) torsion pendulum drive that I have seen.
Pulses are timed by the swinging magnet in most of these cases.
As the magnet swings into the coil, a tickler winding caused the transistor to turn
on. This causes a feedback loop that increases the feedback holding the current
through the coil and causing the swinging magnet to increase speed. The initial
feedback is limited in time by a capacitor ( usually ), timed such that it can only
start the transistor. Once the magnet begins to move out of the field, a reverse
voltage is picked up by the tickler winding. This causes the transistor to turn off
and wait for the next passage of the magnet.
This is very similar to the way the ATO clocks work, with mainly slight changes to
allow it to work with silicon transistor, instead of germanium.