I collect US Military clocks, and have several IBM masters in my collection. Here's some pic's of both a US Navy and a US Army Air Forces model 35 IBM master clocks.
This is a Model 35 master clock that came out of one of the Naval Aircraft Factory buildings in the Philadelphia Navy Yard in the 1960's . It's pretty much a standard Model 35 with an Invar pendulum except the pendulum and weights were finished in Silver/Grey wrinkle paint. There's no power supply components or relays inside the case, the contacts are all wired to terminal strips on the top of the cabinet.
This is a US Army Air Forces Model 35 Master with a Mercurial pendulum. The only difference is that they overprinted the dial with red 13-24 numbers. I've seen 3 others like this with the standard cams and contacts to drive a slave system. What make this clock interesting is that this clock isn't actually a Master, It doesn't have any of the necessary contacts or cams. There are no holes in the case or any evidence of any wiring ever being installed. It appears that it was built as a very accurate wall clock. (The pic of the paper label on the back is from the Ebay ad when i bought the clock, I have the clock rated down to about 9 seconds /month so I don't want to take it down for a better picture)
This is a Model 35 master clock that came out of one of the Naval Aircraft Factory buildings in the Philadelphia Navy Yard in the 1960's . It's pretty much a standard Model 35 with an Invar pendulum except the pendulum and weights were finished in Silver/Grey wrinkle paint. There's no power supply components or relays inside the case, the contacts are all wired to terminal strips on the top of the cabinet.
This is a US Army Air Forces Model 35 Master with a Mercurial pendulum. The only difference is that they overprinted the dial with red 13-24 numbers. I've seen 3 others like this with the standard cams and contacts to drive a slave system. What make this clock interesting is that this clock isn't actually a Master, It doesn't have any of the necessary contacts or cams. There are no holes in the case or any evidence of any wiring ever being installed. It appears that it was built as a very accurate wall clock. (The pic of the paper label on the back is from the Ebay ad when i bought the clock, I have the clock rated down to about 9 seconds /month so I don't want to take it down for a better picture)
