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  1. #1

    Default Junghans ATO ???

    I bought a Junghans ATO clock at a garage sale. I don't really know much about clocks, but this looks pretty cool. The problem is it works intermittently. It looks like an anniversary clock with a pendulum of sorts and is battery powered. I think the pendulum swings through an electro magnet. The only identifying data are the words "Junghans ATO" on the clockface and a number, 315261, stamped on the vertical piece of the clock. The clock has a brass base, about 8" in diameter, with a glass globe and a white face with arabic numberals. It looks like the original battery box has been replaced with something that was cobbled together from another device, although it is enclosed in an original housing so it looks ok. The clock runs great, then stops and will not resume operation -- until it is willing to do so. I can give the pendulum a push and it may come back to life, or it may not. It has been running for 36 minutes now since the last push! I am finding precious little info about this clock on the internet, but this site seems to have some info about these clocks. Anybody know what I have, or what I might do to get it to run continuously? Thanks.

  2. #2

    Default Re: Junghans ATO ??? (RE: Dan)

    Dan: Welcome to the message board. I'm going to move your thread to the electric clocks forum so it can get better exposure and the answer you need.
    “If one tells the truth, one is sure, sooner or later, to be found out.” - Oscar Wilde

  3. #3

    Default Re: Junghans ATO ??? (RE: Dan)

    Well given serial number of 315261 It may or may not be one of two variants. The older (and in my opinion more collectible) variant has a second hand above the main hands in a wheel of its own (latter models do not have this). I don't know when the production switch was made, but I have one with serial #307000 what still has the second hand. You may notice that the general gear layout is very similar to the Kundo electric models, this was the design from which that clock was based. Also, the second hand "ticks" 75 times in a minute, which is a bit odd to watch.

    Second, this is likely to be a mechanically switched unit (not a magnetic trigger and a transistor as per latter ATOs and Kundo units). You will see the switch to the right of the works,see below picture of this. Most stop-start problems are due to this switch not making proper contact (it only has to pulse for an instant). The two contacts can become pitted and this is more of a problem to fix. Another common problem is the suspension being bent, if you see any side-to-side wobbles consider replacing it (it uses the same suspension spring as a Kundo, ten bucks from the normal sources).

    The hobble together battery is common and not a big deal as long as it is being driven by a 1.5 volt batter (you will also often see two in parallel- but not series! ) The original battery used as a rather odd ball type called a "size 3" which is hard to come by and offers no benefit other then appearance. Most people use a simple modern battery, but I have seem some people get one of the old type 3s and then hollow it out and put a regular c-type in the space, others justs hid it in the brass shell that covers the back.
    Attached Thumbnails Attached Thumbnails ATO switch close view.jpg  
    Last edited by DC Kelley; 07-12-2009 at 04:54 PM. Reason: typos

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