ATO Gebruder Junghans ato help

[Kelly H]

I just picked up a Gebruder Junghans ato. From what i have read it takes a 1.5v.When i got it , it had a 9v oh it. works ok bet the pendulm hits the coils.
But when i put a 1.5 to it, it wont run. I am using new battery's. Eany ideas?

 

[Jmeechie]

Hi,
Have you tried reversing the battery? Also, what size battery? The AA doesn’t have enough to run one of these. It’ll take 3 AA in parallel to achieve enough amps to energize the coils.
The only other issue besides someone screwing up all the adjustments is the contacts are dirty. You can check for resistance with a meter. If they need cleaned be careful as they are rather delicate and can be damaged easily.
Cheers,
James

 

[whatgoesaround]

If run on 9v the contacts could be pitted. Also, the gap between the contacts might need a slight adjustment. You could try a bit of electronic spray cleaner on the contacts or gently rubbing them with something like denatured alcohol, but be careful not to bend them out of position and not to leave any debri. The side contacts can often be flipped to expose the other side. I have the same model running on a C battery.

 

[Kelly H]

one D size will not run it. 2 C size in series and its still running the pendulum is not hitting the sides. This would give the clock 3v?
But how far is the pendulum suppose to travle side to side?

 

[Jmeechie]

The travel of the pendulum is based on adjustment factors. Primarily point at which the point close, which should be at as close to dead bottom of the swing. The advance arm should not drag across the tooth on the return swing.
Did you try reversing the battery polarity? These clocks are polarity sensitive as the flow of voltage determines the polarity and the magnet is a fixed polarity!
I just finished an ATO I picked up that was “good for parts” and was 2 Do’s in series 3v and wired backwards! Long story, higher voltage will grab the opposite magnet in the swing and I’ve watched it, wobble or bounce the pendulum in mid swing! This poor clock had everything screwed up, dirty contacts, advance arm driving deep into bottom of tooth to advance, points closing post dead bottom swing, and battery(s) wired backwards! and, movement drowned in WD40!
By the way, the contacts barely touch to make connection! Have you tried to clean the contacts yet?

 

[Kelly H]

This is my first clock so I am going slow. The - is to the coil either way was is the same. I would say the coils are good because it ran with a 9V that it was set up for. I have wiped off the contacts. But not cleaned or oiled the clock. Was trying to get as much info as i can first.
Is there any reference material out there I can get?

 

[Jmeechie]

Here’s the thing, ATO movements are battery polarity sensitive. The pendulum is a North / South magnet being attracted by the magnetic polar pull of the coil.
I believe there is manuals available in the lending library. ATO made his design available for all to use so i know there’s plenty of companies like Junghans, Hettich and such used this design and I believe Junghans produced a service manual in German for servicing these clocks.