Bt Connections / Telephone Extension / Phone Fault Bt Info

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Grandad?

Anyway, although there should only be one master socket per line, you'll find depending on line conditions you can run more than 1 quite satisfactorily. I have on many occasions for one reason or another.

 
Yes, boy? Are you sniffing around for more money again?

Fax is a great step up from teletype (paper ribbons with 7 punched holes in - anybody know what I`m talkin` about?)

I wouldn`t be without a fax mate - business wise, it can save a lot of hassle, AND speed up payment!

 
Older cables 2 = Blue.

3 = Green.

4 = Brown.

5 = Orange.
Some conversions to 431/631 jacks were wired that way, but you'll also find green & brown the opposite way round.

In the GPO days, blue & orange from the incoming line were B & A respectively, with green being used for local earth where required for party line operation or PBX recall. Hence green was often used on 4 for local earth to PBX extensions with the new jacks, and brown for the bell feed/shunt on 3 for domestic extensions.

These days, many people are totally unfamiliar with the older color code, so it's not unusual to find the wiring completely mixed up from the old standard where somebody has tried to add an extension in more recent times.

BT Dropwire comes with 2 pairs of cores.Pair 1 is WHITE & ORANGE

Pair 2 is BLACK & GREEN
Larger sizes can also be found in some domestic properties. 4-pair is not that unusual:

Pair 1 - Orange / White

Pair 2 - Red / Slate

Pair 3 - Blue / Brown

Pair 4 - Green / Black

BT line voltage is -48v DC wrt earth across pins 2 and 5, supplied at 40mA.
The line current will depend upon the resistance of the loop, which is largely dependent upon distance from the exchange. On long loops, you may see a considerably lower current, down to about 25mA.

On the 48V vs. 50V issue, these are the nominal voltages which are specified on opposite sides of the Atlantic. In North America the nominal battery voltage is always shown as 48V, but in the U.K. it's always been 50V.

 
Yes, boy? Are you sniffing around for more money again?Fax is a great step up from teletype (paper ribbons with 7 punched holes in - anybody know what I`m talkin` about?)

I wouldn`t be without a fax mate - business wise, it can save a lot of hassle, AND speed up payment!
i do i do sir

crypto ;)

 
quick brown fox on a loopthey were the days
ryryryryryryryry......... :)

^^^^ - Should be all caps, of course, but the forum software doesn't seem to want to allow it!

 
'J' Bell's as well as RYRYRYRYRYRYRYRYRYRYRYR? or is me brain going senile again?

:|
Yes, BELL was on the figure-shift of "J" in the I.T.A. No. 2 alphabet. There were other 5-element teletype codes which had it in a different place though.

The "RYRYRY" sequence was used as a test, since it resulted in a stream of 01010101...... over the line, which could be used for testing the response of certain parts of the machine, and for tuning where FSK radio transmission was employed.

 
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