[Asterisk-Users] OLD PA system.

[Thomas Kenyon]

John Novack wrote:
>
>
> Bob Chiodini wrote:
>
>> You might put 600 ohm/600 ohm matching transformer to isolate the
>> port and the amp.  Should also maintain loop current if needed.
>>
>> Bob...
>>
> FXO ports do not  generate loop current, they detect loop current from
> the Central office.
> Think of an FXO as  a controllable switch and matching transformer.
> An FXO port will give Asterisk/Zaptel a red alarm without loop
> current, so that probably won't work for a PA system that doesn't
> supply battery.
> What's wrong with using the (usually) unused sound card built into
> many machines?
>
> John Novack
Mostly it uses the wrong impedance, and I know I can probably get an
impedance matching transformer, but I'm not allowed to spend any money
that I don't need to.
(Otherwise I'd have replaced the amp in the first place with one that
didn't fall from the arc).