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    American IBM Simplex US Capitol Clock

    The circuits are 4000 series CMOS, Low power and tolerant of a wide range of power supply voltage, so good for this sort of applications. I'm pretty sure the date codes are 1984-1986 -- and I note the PCB itself has the code 8817 which might mean it was assembled in 1988. The web page I...
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    American IBM Simplex US Capitol Clock

    Yep that would be the area of interest. Integrated circuits of the era had date codes of the form YYWW YY being the last two digits of the year and WW being the week. Also the part number (and the type of logic circuits) will also give a clue as to the date.
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    American IBM Simplex US Capitol Clock

    Only took a few seconds of googling to find the explanation of what the lights are for: Bells, Buzzers, Clicks and Clocks
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    American IBM Simplex US Capitol Clock

    "Architect of the Capital, Electronics Engineering Division"... So whatever it is, it was likely made in small quantities probably using an off-the-shelf simplex movement as the basis. From the overall construction techniques and appearance it is no older than the mid 1960s, and more likely...
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    Making a new WW bearing dust cap

    Yes ssl certs can be a pain. I followed the link and the cert presented is what I assume is the old one expired August 29, 2019 -- I note that it was created on May 31, 2019, so pretty short expiration time. For whatever reason your HTTPS server (Apache?) has not picked up the new cert.
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    American Majestic Electric Clock; how to update/protect for safety?

    If the coil is in good condition then the danger is pretty low. If the clock has a metal outer case then I might consider a 3-wire plug instead of 2-wire as that will provide shock protection, but not much protection from a potiential fire. As for a fuse, a thermal cutoff is series with and...
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    Limiting Strike Hours

    Nothing complicated about it it's the same system, just automated. The linear actuator pulls the same rope pulling at whatever hour the chimes should stop and lets it go the following morning. There's probably dozen's of other way to implement it as well.
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    Limiting Strike Hours

    Indeed you could probably build something with off-the-shelf parts for most of the complicated bits. A linear actuator to actually engage/dis-engage the hammer from the bell, a controller of some sort and a timer.
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    American st electric motor question

    The easiest way is to count the teeth on all the wheels and pinions and then do the calculations. I have found that the easiest way to count teeth is to photograph the wheel and then in photoshop (or similar photo editing program) mark every 5'th tooth around the wheel (which is easy to do...
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    IBM clock set time It is similar in operation an SCR. A voltage on the trigger connection starts a mercury arc that then allows the tube to conduct until the current goes to zero and the arc quenches. The trigger needs ~ 70-100 V to trip. The transformer and...
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    Rotary table set-up

    The part you want is the #3701 "Right Angle Attachment". There is also the #3750 "Tilting angle table"
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    "Warning" vs. "Arming"

    There is no engineering reason for the warning to have any sort of precision. As you have observed is is a gentle slope on a slow-moving cam that at some point trips the mechanism to go to the "warned" stated (for lack of a better term). What matters is that the strike happen on the hour, and...
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    Need advice for upgrading a slave clock setup

    Indeed it would be sad if they shutdown WWV. There are alternatives: GPS modules are now typically $20-30 and can provide extremely accurate time as long as they can receive the satellite signals. If there is internet connectivity, then computer clocks synchronized from the Web can also...
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    "Warning" vs. "Arming"

    I believe that the warning state is a mechanical necessity. Consider that the strike mechanism is triggered by a cam on the relatively slow turning minute hand shaft. If you implemented a mechanism where the hi-point of the cam means "start the strike" then the cam lobe has to be narrow enough...
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    Rempe self-winding - questions on electrics

    That is indeed a well-written article, and I agree that the back-to-back zeners is a good approach, I like the fact that it is a polarity in-sensitive, meaning that someone with less electrical knowledge is less likely to get wrong. One option the poster doesn't explore is a diode plus a...
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    Thread Pitch on 8mm Chuck

    I created this page in our "encyclopedia" some time ago: There are both 40 TPI thread and 0.625mm pitch (40.64 TPI threads), and also 0.75mm threads on the new ones from the Orient.
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    torque meter wanted

    I you are trying to measure the torque capability of a running motor as speed then indeed as you have seen the available instruments get pretty pricey pretty quickly. The easiest mechanism is some sort of adjustable brake and then measure the torque on the static side of the break (for which...
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    Precise Watch Timer

    Most small Neon lamps take about 90V to start conducting, but once they do the current must be limited (typically with a resistor). Can you post a picture of this particular lamp? If is your common NE-2 bulb you can test it by connecting it directly to the 120 V AC mains with a 200k resistor...
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    American Simplex 2850 Transmitter Manual

    Certainly looks like it has a decent chance of working. Do you have an oscilloscope so that you can check that the replacement is working properly and not oscillating?
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    Unusual Data Time, Inc, digital clock???

    I'd be interested to see the internals... Is is a mechanical? (clock motor driving rotary switches), or digital electronics?

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Ptolemy's Course of the Planets displayed by CLockwork by Tom McIntyre