US GE Clock 60Hz
 

I have a 1950s American GE electric clock, 117VAC/60Hz. Very ordinary, but it has strong sentimental value. I attach a photo.

Obviously it won't work here in UK, even with a voltage transformer. It will run slow because of the difference in mains frequency.

Can anything be done? Are these movements standard enough that I could replace the original movement with one from a vintage UK clock? Could one perhaps even just change one gear for one with a different number of teeth?

I have not opened up the clock yet so no idea what it looks like inside.

Thanks!

Re: US GE Clock 60Hz
 

Hi Martin,

I think an external frequency converter is your best bet, if funds permit:

http://www.electric-clocks.co.uk/Fre...cyconvert.html

Re: US GE Clock 60Hz
 

Thanks, that's cool. I knew that these converters existed, but the only ones I had seen before were for larger applicances and were both physically bulky and expensive. The one you have linked to, while not cheap by any means, seems like the perfect solution for my issue.

Re: US GE Clock 60Hz
 

One gear wouldnt be enough - at least two would be needed.
Have a look first! Nick's link seems good if funds allow.

Re: US GE Clock 60Hz
 

You could also just build your own driver box. You need an accurate 60Hz sine wave, some sort of power amp (like a class D output chip) and a mains transformer wired 'backwards' to create the necessary 117V drive signal. It would make an interesting project if you enjoy practical tinkering.

Re: US GE Clock 60Hz
 

Yes, see here:

https://www.vintage-radio.net/forum/...d.php?t=171888

I liked the sound of Hamid's suggestion in post 8, which sounds like what Mark Lines' unit does.

Note that I haven't heard from the friend who owns the clock for ages, so nothing's happened yet.

Re: US GE Clock 60Hz
 

This problem comes up quite often. How to run an imported clock on a different mains frequency? There are several solutions. The commercially available frequency converter as mentioned above is the easiest answer - just plug and play - but it is expensive, costing considerably more than most electric clocks are worth. (Of course, if the clock is of sentimental value, you may consider the cost of the converter to be a price worth paying.)

For a DIY approach that requires only a few parts costing a fraction of the price of a commercial converter, I found this:
http://www.romanblack.com/one_sec.htm
Near the end of the page, it describes a crystal-controlled inverter and a mains-locked 50Hz to 60Hz converting inverter exactly like the commercially available frequency converter from electric-clocks.co.uk
I've attached the circuit diagram. The source code for the PIC chip is here:
http://www.romanblack.com/onesec/ZE_SineConverter.htm
This will follow your local mains frequency for good long-term accuracy.
There's also a crystal-controlled version which will be as accurate as a quartz clock. It can generate 50 or 60Hz depending on the crystal, so you could change it to use a British clock in the USA if you needed to. Here's the source code but no circuit diagram: http://www.romanblack.com/onesec/ZE_SineInverter.htm

Re: US GE Clock 60Hz
 

Thank you everyone. For the moment I have adopted the solution suggested by Nickthedentist and purchased the converter he suggested.

I am indeed a tinkerer/builder. My ham station is entirely homebrewed from 1950s/60s designs. I'm British but lived in the USA for a long time and moved back to UK three years ago. The clock is my shack clock from America and is essentially identical to the one in the photo on the cover of ARRL's book, "How to Become a Radio Amateur" from 1968 (see attached photo). Hence the sentimental value....

Re: US GE Clock 60Hz
 

I love tinkering and building too but sometimes an off the shelf bit of kit is the right choice. For example I got a "digital delay/lip sync" box from Scotland, OK I could have made it for less than a tenner and hours of programming, 60 quid and it works a treat. https://www.js-technology.com/store/...roller=product I am still wondering why I need one though.

Re: US GE Clock 60Hz
 

So I went ahead and purchased one of the suggested voltage/frequency converters to run my American AC clock in the UK. It works beautifully in terms of running the clock, which is keeping perfect time.

However, the clock is in a ham radio shack and the "system" (converter plus clock) is generating considerable RFI on the ham bands. I have tried several things, including putting the converter in another room and running a cord to the clock, but that made no difference. I also tried placing ferrite beads on the cords, but that also made no difference.

I attach a photo of the clock below (bog standard American GE from the 1950s). Does anyone know how feasible it might be to remove the mechanism and replace it with a battery mechanism, thus eliminating the risk of RFI altogether? If so, any suggestions for the best "donor clock" to cannibalize from?

The clock is a "glow in the dark" model (constant very low level lighting from a bulb inside) but, in the event of conversion to battery power, I don't mind losing that feature in the interest of longer battery life.

By the way, in the photo, the clock is literally on top of my radio receiver, just to make a nice picture. During the RFI tests, the clock was not in that position, but was actually about a foot away on the table to the left.

Thanks!

Re: US GE Clock 60Hz
 

Ferrite beads on the mains cable to the converter and at both ends of the cable to the clock?

David

Re: US GE Clock 60Hz
 

Yes, exactly. Plus, a few more midway along the two longest cables.

Re: US GE Clock 60Hz
 

In a brief browse on Amazon, I found several modern analog battery clocks (with quartz movements) that are about the same physical size as my GE. I suppose the question is how easy it would be to mount the movement and attach the (original GE) needles on the new movement, plus, whether a difference in the weight of the needles (compared to the original clock) could cause it to run slow or fast. I would imagine it would run perfectly (because of the quartz movement) or, not at all.

Re: US GE Clock 60Hz
 

The converter will have lots of switching electronics inside, so it's not surprising that there's an RFI issue. The first thing to try is putting it in an earthed metal box or even wrapping it in kitchen foil (watch out for shorts though).

It should be easy enough to fit a quartz movement, but that's heresy to many here. If you choose to take that route you can buy them new, or scavenge them from clocks bought from car boots, charity shops or flea markets. Seiko and Actim use good movements - in fact any brand that you've actually heard of should be OK. Watch out for movements with overly loud ticks.

The weight of the hands won't be an issue.

Re: US GE Clock 60Hz
 

I understand that. I own a lot of vintage radio and test equipment (mainly from the 1950s and early 60s) and usually try to restore them sympathetically back to their original condition. This case is a little different for me. You will find hundreds of clocks like this one at American "garage sales" but this one has sentimental significance as my "shack clock". It needs to work, not generate RFI, and look the same as the original. The option of installing a battery movement makes sense for me. I could go on trying to eliminate the RFI, but *any* RFI is bad news inside a ham shack so the battery solution is a good one.

Edited to add: It will be functionally almost identical to the original ... it's not as if I'm turning it into a cocktail cabinet.

I thought so, but thank you for confirming it!

Re: US GE Clock 60Hz
 

OK done. I've ordered a Seiko movement that will fit inside the original case. Hopefully the hands from the GE will slot onto the Seiko shaft. The rest should be easy, I just need to cut a small aluminium mounting plate for the new movement.

Re: US GE Clock 60Hz
 

Good luck with it.

I have a Seiko wall clock in the kitchen which keeps near perfect time (less than 5 seconds drift in 6 months - that's the setting interval for summer/winter time).

Re: US GE Clock 60Hz
 

I've always liked Seiko timepieces. I had a Seiko analog quartz wristwatch for decades but somehow I lost it, not that long ago. It, too, kept almost perfect time.

Re: US GE Clock 60Hz
 

I've obtained the donor clock, a Seiko. It will be a good fit to go inside the original GE case.

However, the holes on the hands of the donor clock are smaller than the original hands and I need to mount the original hands on the new movement.

See photo.

What is the best approach?

• Try to find bushings the fill the gaps (tricky because they would need to be very thin). If this is viable, what is a good source for these bushings?
• Cut the hands and glue the old ones onto the stump of the new ones (the old hands are metal, the new ones are plastic). Probably doable, possibly fragile, possiby ugly if not done really carefully leaving a minimum of stump from the new hands? Also, a couple of the old hands protrude on both sides of the shaft, and I would have to use only one side, thus changing the appearance of these vintage hands.
  
  I have measured the thickness of the hands with a micrometer: the old hands are only 0.4mm while the ones on the donor clock are 0.7mm. This is good, it means that the old hands will fit on the new movement without jamming each other.
  

Re: US GE Clock 60Hz
 

I would use the hands from the donor movement to mount the original hands. You should be able to modify both sets of hands to make a neat job of it. Superglue should make a decent enough bond.