Help hacking a quartz clock...I'm so lost.

Thread Starter

holychachi

Joined Jul 13, 2010
7
Hello all,
First let me say I'm new here and very very new when it comes to the world of electronics. Surprisingly electronics is seeming hard to crack into. So much to learn, electronic components, programming, and on and on. It's overwhelming to say the least. But it seems to be a great hobby with the almost limitless directions you can go and things you can create.

As for the problem at hand...you guys will probably scoff at this but when you are done calling me a noob and ROFLing at me, I would appreciate any advice and direction you guys can provide. I'm trying to build a clock where the minute hand moves once per minute in a swift motion like the second hand. I know I could do this by using some type of stepper motor, which i am interested in how you would do that, but I would really like to do it by hacking a quartz clock. I found an interesting article at http://josepino.com/circuits/one_second_timebase, which kind of inspired my idea. I'm wondering if there is a way to turn that 1hz pulse into uhhh 1/60hz...? In other words turn that once per second pulse into a once per minute pulse. This, it seems to me, would essentially turn your second hand into a minute hand.

So if I can just find a way to get the minute hand to move in pulses 6 degrees at a time once per minute, then I will be happy. Then of course I can follow this thread up with a 'Need help getting an hour hand on a clock to pulse once per hour' thread. Sorry if I dumbed down the forums too much, but hopefully one day I can be the one answering the silly beginners questions. Thanks in advance for all your help, can't wait to see what you guys come up with!

Charlie
 

SgtWookie

Joined Jul 17, 2007
22,210
I'm afraid you have it backwards; instead of 1/60 Hz, you'd need 60Hz if you wanted the minute hand to sweep all the way around in 1 minute.

However, the clock Jose' Pino hacked used two 30Hz signals that alternated; ie: one pulsed high and then the other pulsed high in order to attract and repulse the rotating magnet using the coil.
 

ErnieM

Joined Apr 24, 2011
8,006
Charlie: I actually like your idea for the minute hand and think it would look pretty cool, but what about the hour hand? At 3:59:59 is it still going to be pointing directly at 3 for one more second? someone might mis-read that. *I* might misread that. Just a question, it's your project. :p

I don't think the electronics is that difficult (but that's what I do) but i would find hard is getting all these hands to move up thru the same shaft: both (or all 3) hands on a clock go thru the same hole. Are you good with gears and such?
 

KMoffett

Joined Dec 19, 2007
2,770
....However, the clock Jose' Pino hacked used two 30Hz signals that alternated; ie: one pulsed high and then the other pulsed high in order to attract and repulse the rotating magnet using the coil.
No. The quartz clocks output two ~30mS wide, 0.5 Hz pulses, 180° out of phase.

Ken
 

CDRIVE

Joined Jul 1, 2008
2,219
How does that PNP turn on? It would seem that a resistor from the base to GND would be needed to forward bias the base while either clock output is low. Am I missing something?
 

Thread Starter

holychachi

Joined Jul 13, 2010
7
Do you know programming or anything concerning stepper motors
Unfortunately no and no, but I am interested in learning both.
Stepper motors really fascinate me as does programming. I'm thinking about trying to Learn C++. Would also consider any suggestions.
 

Thread Starter

holychachi

Joined Jul 13, 2010
7
I'm afraid you have it backwards; instead of 1/60 Hz, you'd need 60Hz if you wanted the minute hand to sweep all the way around in 1 minute.

However, the clock Jose' Pino hacked used two 30Hz signals that alternated; ie: one pulsed high and then the other pulsed high in order to attract and repulse the rotating magnet using the coil.
No, I don't want the minute hand to go 360 degrees in one movement, I want it to move 6degrees in one sweep. I basically want the minute hand to step like the second hand does but once per minute.
 

Thread Starter

holychachi

Joined Jul 13, 2010
7
Charlie: I actually like your idea for the minute hand and think it would look pretty cool, but what about the hour hand? At 3:59:59 is it still going to be pointing directly at 3 for one more second? someone might mis-read that. *I* might misread that. Just a question, it's your project. :p

I don't think the electronics is that difficult (but that's what I do) but i would find hard is getting all these hands to move up thru the same shaft: both (or all 3) hands on a clock go thru the same hole. Are you good with gears and such?
I have no real experience with any of it including gears but I have been playing around with gear trains and ratios on Algodoo. I don't know how I could get them built but I'll cross that bridge when I get to it.
 

Thread Starter

holychachi

Joined Jul 13, 2010
7
Could you alter the counter so instead of counting to 32xxx it counts to 60 times that before emitting a pulse? Does that make sense?
 

THE_RB

Joined Feb 11, 2008
5,438
No, I don't want the minute hand to go 360 degrees in one movement, I want it to move 6degrees in one sweep. I basically want the minute hand to step like the second hand does but once per minute.
Then it is a mechanical issue primarily. You need to remove the first set of 60:1 gearing between the solenoid escapement and the clock gears and attach the escapement (ratchet thingy) direct to the minute hand not direct to the second hand where it is now.

Once the mechanical mod is done you drive the solenoid with a +/- pulse every 30 seconds, or better still every 59.5 and 60 seconds if you are using a microcontroller.
 

CDRIVE

Joined Jul 1, 2008
2,219
How could any one hack it and post it with pictures when it is wrong?
The bigger question is how long has he had it up there and not noticed his error or not received a wakeup call from a reader? Hey, people create web pages all the time and don't care to even spell check it!
 
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