[GreenKeys] Far OT: audio inputs

[pdwills at cedarknolltelephone.com]

I've seen 600 and 900 ohm for wire and cable at voice
frequency.  Most of my transmission equipment is designed to
terminate at 600 ohms.

I believe 135 ohms is the impedance seen by carrier
frequencies.

PDW


----- Original Message Follows -----
From: Jim Haynes <jhhaynes at earthlink.net>
To: gil at baudot.net
Cc: greenkeys at mailman.qth.net, eugene at hertzmail.com
Subject: Re: [GreenKeys] Far OT: audio inputs
Date: Mon, 16 Feb 2009 14:44:54 -0600 (CST)

> The impedance of an open-wire pair runs around 600 ohms as
> well.
> 
> I have see 135 ohms in some telephone test equipment, but
> I don't know what kind of circuit has that impedance.
> 
> 
> jhhaynes at earthlink dot net
> 
>