Phone line as SW antenna [12-Jul-06]
On 04/10/2014 02:55 PM, George Cornelius wrote:
On 04/01/2014 03:00 AM, William Mcfadden wrote:
You mention that a .01 capacitor blocks "voltages". You mean
DC voltages, of course, because the whole idea is to have it
pass high frequency voltages through. A quick calculation is
that if this is a 600 ohm circuit the time constant is
.01 uf x 600 ohms or 6 microseconds. So switching transients -
like going off-hook, pulse dialing, etc., especially with older
relay-based telco equipment, could still pass through as
relavitely tall spikes - spikes that are ballpark of, say, 2-
20 micro-second duration.
If the spikes are 50-100V (wild guess based on old data).
Then your receiver must be capable of absorbing these without
damage. I suppose a well designed receiver can do this, but
who knows with the cheaper stuff.
Haha. Somebody replied to the the Billbot.
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