[HCDX]: RE: hard-core-dx V4 #460

[Bob Foxworth <bob@xxxxxxxxxxxxxxxx>]

Quoted from:
> hard-core-dx           Friday, March 6 1998           Volume 04 :
> Number 460
> ------------------------------
> Date: Thu, 5 Mar 1998 10:46:17 -0500 (EST)
> From: w a merriman <merriman@xxxxxxxxxxxxxxxxxx>
> Subject: [HCDX]: Another Noise Source - Revisited
> 
> After sending my initial message yesterday I've done some more
> experimenting with this unit.  First, some info about the unit
> which someone asked for:
> 
>         Radio Shack Wireless Phone Jack System, 43-160
>         States that it complies with Parts 15 & 68 of FCC rules
>         FCC Reg Number:  AAOMLA-24509-RJ-N
>         Also, whatever this means  REN: 0.7B
> 
This means, Ringer Equivalence 0.7 Bell.  A standard bell (series L-C
circuit
resonant at 20 Hz to operate the dual chimer) placed a certain load
across
the line. Too many bells paralleled across the line and the CO could not
guarantee enough current to ring them all. When electronic phones were
invented, an equivalency value for the pseudo-bell was created. You are
supposed
to notify your telco when you add these things to your line but no one
ever seems to. You shouldn't exceed about 3 B, I believe.  In the bad
old
days of the Bell System when individuals were prohibited from owning
their
own phone sets, the Telco found illegal extensions in your home by
placing
a step current on your line and measuring the inductive kick back from
all
the bell windings in parallel so what you had to do was disconnect the
spade lug to the bell winding from the L1 terminal on the hybrid coil.

>         Unit was made in Malaysia
> 
> End of hard-core-dx V4 #460
> ***************************
> 
Bob F
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