by Rob-NYC »
Sat May 23, 2015 3:44 am
Here is a brief rundown of Seeburg stepper sequence:
First latter pulse pulls down the latter clapper and closes the two sets of contacts that ride on top of the clappers. One of these charges the hold magnet, the other charges the transfer relay which will remain down until the interval between latter and number pulses.
When the transfer relay falls out at the interval it transfers the next pulses to the number clapper.
Once again two sets of contacts on that clapper act to keep the hold magnet energized. The other set pulls down the two timing relays. After the last pulse one timing relay falls out while copper rings hold the other for a fraction of a second. In this instant the write-in pulse is applied and, on Tormat machines, the scan assembly is pulsed to start.
On the old electro-mechanical machines scan is accomplished when the selection lever is moved to the selected position. This part of the operation is the same from either the keyboard or the stepper.
---You need to check that the selection pin is being moved completely to the selected position when a stepper selection is made.
It is possible that dirty contacts on the stepper wheels or write-in contacts on the timing relays are weakening the pulse and not moving the pin all the way. Then, when the moving contact block's "dresser" comes by it moves the pin all the way to the selected position.
Rob/NYC
"If we believe absurdities, we shall commit atrocities" -- Voltaire