I am in the process of getting an old Telchron Model 700 Electroalarm running. I have posted it about a month ago on this board.
It seems to have a bad B2 rotor and a bad coil. Rather then get the rotor restored I thought I would search the local flea markets, yard sales and junk stores for a working Telechron with a B2 rotor. It took me a week to find one, a Warren Telechron mantel clock for 5 bucks.
It ran, but noisily. I took it apart, removed the rotor from the stator frame, and compared it to the B2 rotor from the Electroalarm. They appear identical. Since I now had a know working coil, I figured I would test the rotor from the Electroalarm with it. This rotor worked as well.
However, when I put the mantel clock back together, after disassembling, cleaning and oiling the movement, the clock ran in reverse. I thought I had switched polarity on the coil wires, so I reversed their connection to the leads. It still runs in reverse. There is only one way to put the movement in the case, due to the cut out for the interuption disk on the dial. The movement is not in upside down, which was my first thought.
My only clue is this: I think I took the rotor out of the coil with the current still on. This would be the same action you would use to demagnetize a watch - place it near the demagnetizer with the current on then move it away from the magnetic field. Is it possible that this somehow switched the magnetic field of the rotor?
I'm puzzled, but like the man says, "I'm learning all the time."
It seems to have a bad B2 rotor and a bad coil. Rather then get the rotor restored I thought I would search the local flea markets, yard sales and junk stores for a working Telechron with a B2 rotor. It took me a week to find one, a Warren Telechron mantel clock for 5 bucks.
It ran, but noisily. I took it apart, removed the rotor from the stator frame, and compared it to the B2 rotor from the Electroalarm. They appear identical. Since I now had a know working coil, I figured I would test the rotor from the Electroalarm with it. This rotor worked as well.
However, when I put the mantel clock back together, after disassembling, cleaning and oiling the movement, the clock ran in reverse. I thought I had switched polarity on the coil wires, so I reversed their connection to the leads. It still runs in reverse. There is only one way to put the movement in the case, due to the cut out for the interuption disk on the dial. The movement is not in upside down, which was my first thought.
My only clue is this: I think I took the rotor out of the coil with the current still on. This would be the same action you would use to demagnetize a watch - place it near the demagnetizer with the current on then move it away from the magnetic field. Is it possible that this somehow switched the magnetic field of the rotor?
I'm puzzled, but like the man says, "I'm learning all the time."
