sundance-communications.com/forum Forums Other TDM Phone Systems 1A2 and Comkey Telephones & Systems Dangers of 1A2

Recently I was trying to pull a line card out to fix the "Pulse Dialing Causes 1A2 to Ring" https://www.sundance-communications.com/cgi-bin/ultimatebb.cgi?/ubb/get_topic/f/35/t/000209.html issue, and I forgot to unplug the KSU, and since the line card didn't have the gray grip where the company label goes, I tried to grab the line card from the back.. I got a good scare and a painful shock and burn on my left middle finger :read: I would prefer to avoid another shock! Thanks.

We would never unplug a KSU to pull a card, but never grab any electronic device by the "traces". You probably got bit by ringing current - It won't ever do any worse then what you got hit with that time, but it's still not fun. Just be careful.

I once heard that "the only lessons you learn are the ones you pay for".

You paid for that lesson. I doubt that you'll forget it.

Sam

There's a reason they call it Hertz. We've all been there at one time or another.

Was there a hole in the top side front; put a small piece of wire in there and puuuuull

Or, a TYWRAP. It won't conduct and give you another "dose".

You need to have familiarity with the equipment you're working on. If you plug and unplug electrical equipment powered with 100 volts AC, you need to be aware that components, especially on 40-year old circuit boards, can explode. You have eight fingers, but only two eyes.

If it's subscriber equipment, the equipment stays powered up, unless it's after hours. On hobbyist equipment, just power the stuff down.

Play safe!

Arthur's advice is excellent!
1A2 is one of the few systems that you can pull SOME cards with power applied and get away with it. I should have mentioned that in my first post. Shame on me! John C.

It was an ITT KTU, and there was no gray label holder thing or a twisty tie so I was just trying to find a way to get it out. Normally I remember to unplug it and I wait for the click sound.

After the Atomic War, 1A2 will take over the world,
Phone Men will Rule!!!! :banana: :banana: :banana: :db: :db: :db: :db: :db:
I am going to practice Diode Matrix ringing and the set up some Busy Lamp Fields, maybe even punch down Fifty 50 pair cables and then Amp them. Might be hard without an Amp tool.

Even harder without the AMP connectors. I don't know about you, but I have made a few terminations on an AMP connector with a teeny-tiny screwdriver. Wasn't proud of it, but, sometimes 'ya gotta do what ya gotta do'! By the way, who still sells them. I used to get mine from North Supply. I've still got a few left, but the time will come, maybe. John C.