[GreenKeys] Current limiting

[Ralph Mowery]

----- Original Message ----- 
From: "Chris Elmquist" <chrise at pobox.com>
To: <greenkeys at mailman.qth.net>
Sent: Tuesday, January 20, 2009 8:33 AM
Subject: Re: [GreenKeys] Current limiting


> I'm a little green on current loop fundamentals-- having grown up in
> the RS232 age...  but is the high voltage really neccessary if you are
> not running a long distance with the loop?
>
Others have given a good explination of why you need the high voltage 
because of the large inductance of the coils.

One other thing is it keeps the oil and dust burnt off the contacts of the 
keyboard.