Terry Streeter wrote:
> [EMAIL PROTECTED] wrote:
>> I haven't connected more than two handsets so I am not  exceeding the
>> magic 4 REMs (whatever they may be).
>
> It's actually REN not REM.  Stands for Ringer Equivalence Number - and
> is used to calculate the loading on the line.  When there is an
> incoming call, the exchange sends an AC signal (can't remember what
> voltage, but may well be in the region of 30V to 50V) down the wire.
> In the good old days this activated an electromagnet which caused the
> bell in your telephone to ring.  Too many phones connected caused too
> much loading to the line and there wasn't enough signal left to make
> the phone ring reliably.  One old phone had a REN of one, and the GPO
> set a maximum limit of four phones allowed to be connected to any one
> line.

50V IIRC.  Also with Broadband the bell wire (No.3) is superfluous.  The 
lines coming in from BT, go to 2 and 5.  In the master scocket there's a bit 
of circuitry to make the bell signal on line 3.  The microfilter does not 
use line 3 at all.  Each one has it's own "No.3 generator" for the phone 
outlet socket built into it.  So if you have your extensions wired up with 
lines 2, 3, and 5 - then you actually add more noise to the line as the 
third wire acts like an aerial.  I disconnected line 3 and got a 30% speed 
increase.

Ron Jones
Process Safety & Development Specialist
Don't repeat history, unreported chemical lab/plant near misses at 
http://www.crhf.org.uk
Only two things are certain: The universe and human stupidity; and I'm not 
certain about the universe. ~ Albert Einstein 


Reply via email to