Wish someone had told me that when I was trying to build a ring circuit.

Oh well I guess I know now. :-)


- Mike

"Dave D" wrote in message
...

"Michael Kennedy" wrote in message
. ..
there are little circuit boxes that immitate the phone line, last I saw
one about 60 bucks

Thats the way to go... Getting the operating voltage (48vdc) isn't that
hard just hook up 4 12 volt batteries in series with an 800 ohm (If I
remember correctly) reisistor on the end. Getting a 20hz ringtone is the
difficult part since the wall current is 60hz.. I never figured out an
easy way to make my phones ring.

- Mike


There's several easy ways to generate a 25Hz at 96v, one is an old
fashioned multivibrator driving a 120V/12V transformer secondary, (ie a
25Hz inverter) and adjusting the multivibrator's supply down to get 96V.
It's rough and ready but there's no reason why it shouldn't work, and it
uses a few standard, off the shelf components.

Dave