Vintage neon clock running fast

[Solid Gold Amusements]

Hello!
I am new to this forum and cannot find anything that is the same problem I have.
I was fortunate to fine a nice advertising neon clock from the 1950's at a flea market last year and installed it on the side of my building. The clock runs and the neon works fine. However, after a few days I noticed it was three hours fast. I reset it thinking maybe it lost power during the week for some weird reason. But it has done it again twice now but only the hour hand. The minutes seem to stay within reason. Any ideas?? Thanks!! Bob

 

[barry]

So, if the clock was exactly 2 hours fast, wouldn't the minute hand look 'correct'? How do you know the "minutes stay within reason"? Maybe this clock was designed to run off 50Hz, and you're running it off 60Hz. Here's a test: run the clock for 5 hours. If the clock has advanced 6 hours, that's your problem.

 

[albbg]

Just an idea.
These type of watches usually generates its internal reference clock from the main supply frequency. Possibly you are supplying it from a 60Hz main supply instead of a 50Hz main supply.
In this case I expect a 60/50=1.2 ==> 20% faster running, but since the dividers are designed to generate an integer number of pulses with 50 Hz, using a 60 Hz the non integer part of the division is lost, slowering a bit.
But as I said, is just an idea.

Sorry Barry, I was writing when you posted. I just realized I've posted the same idea you posted

 

[Solid Gold Amusements]

Thanks guys. I am doing a test and will check tonight. I did check the second hand and it is right on to the minute. Wouldn't it move faster? I reset the clock an hour ago so let's see what happens. I will post tomorrow. Bob

 

[Gorgon]

If this is a vintage clock, I suppose it is driven by an async motor from the grid frequency. You should see that the clock is too fast on the seconds hand, if the frequency is wrong.

If the problem is only related to the hour hand, there may be a mechanical problem, like missing teeth on a cog wheel or something in that area.

 

[KlausST]

Hi gorgon,

I suppose it is driven by an async motor from the grid frequency

I´m sure you meant "sync motor"

Klaus

 

[Solid Gold Amusements]

Good morning everyone!
Well. I checked the clock at 6:30 and 9:30 last evening and it was right on. I checked it this morning at 7:00 and both hour and minute hands were perfect. I am baffled at this now. So, I will update later tonight. If all of a sudden there is a change, then I agree with Gorgon that maybe a bad tooth on the hour hand section. Again, thanks everyone. Bob

 

[Gorgon]

Hi gorgon,



I´m sure you meant "sync motor"

Klaus

I did, got an A too much there

 

[Solid Gold Amusements]

Well, I have been checking this clock every few hours and right now it is 100% on time!!! I have come to three different conclusions.
1. It's possessed.
2. This was just my imagination or I am going off the deep side.
3. My 83 year old Mother in law next door is sneaking over here in the night changing the time to drive me crazy.
Anyway, until it does something funky this will be my final post for this subject.
Many thanks to those of you who posted your thoughts on this.
Bob

 

[barry]

The time is now: 12:61