[GreenKeys] Smoke and Fire

[Michael Zahorik]

Well...... it seems like only a few hours ago, I was talkingabout how well my ASR33 unit was working. This evening I was reading a papertape into my PDP8E and half way through the read, I noticed smoke and fire insidemy ASR33. Turns out the distributor trip magnet caught fire. Looking at thecircuit I find that it is very simple. This coil is 120 VAC, protected by a 3amp slow blow fuse (which did not blow) and the only control that I see is thetape tight/out or reader switch off contact. I have removed the coil and itappears to have burnt in mid coil, I can see red wire at the top and bottom.This coil reads open and I see no short to the core. This magnet has a numberon it, 1800853. While the magnet is out, re energized the unit and there are noproblems, smoke and/or fire that is. I can read 120 VAC at J4 pin 11 & 12,when the unit is in either local or line and there is paper tape in the reader.If the tape is removed or the Local/Line switch is turned off the 120 VAC goesaway. I'm betting the coil somehow shorted internally either to itself or thecore (ground). What are my options on finding a replacement magnet? Thanks forthe help. Mike Zahorik (414) 254-6768
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