According to the Leviton "Requirements Beyond Jacks and Cable:An Installation Guide 3RD Revision" it is regarding 66 Blocks and wiring 25 pair wiring to them

[gregg dot drwho8 atsign gmail dot com]

Hello!
On Pages C-2 and C-3 they describe how to make use of an RJ21X connector and the 25 pair bundle and how to punch the bundle down to a 66 Block termination array.

The illustration on C-3 shows one bundle punched down on the left, and the same on the right. There are empty terminals in between them.

Now the question, what happens when the installer needs to make connections between the right and left handed bundles?

Yes I was asked this by a customer of mine several days ago. I described what's seen inside the Leviton book, since (I hope) that particular book is a part of most system installer's libraries.

The customer was watching me install a system that would make use of one of the supposedly dead pairs on that bundle.
-----
Gregg gregg dot drwho8 atsign gmail dot com
"This signature isn't here."

[Doug McIntyre]

Post by gregg dot drwho8 atsign gmail dot com
On Pages C-2 and C-3 they describe how to make use of an RJ21X connector and the 25 pair bundle and how to punch the bundle down to a 66 Block termination array.
The illustration on C-3 shows one bundle punched down on the left, and the same on the right. There are empty terminals in between them.

I don't have that book, so I'm just guessing what you are asking.
Only found references to it online, but no sources online.

I assume you have the varient of a 66 block that has 4 pins across,
with the left two pins solid, and the right two pins solid.
(ie. a split 66M) that is most common.

Most people aren't using bridge clips now-a-days to make a connection
from left to right, as done in the ancient days of telco-dom.

But usually they just use both sides of the 66-block to terminate wires of
the same function.
As the come inbound, they'd be located on the outer pins on both sides.

Then to connect to it, you'd run cross-connect pair from the inner
pins of the solid two (from whichever side) off to the block/wires
you are cross-connecting to on the inner pins.

Ie. lets see if I can make an ASCII picture.

Cross Connect
|------------------|
+=========+ +=========+
pr1| + + + + | pr1 | + + + + | pr26
pr1| + + + + | pr1 | + + + + | pr26
pr2| + + + + | pr2 | + + + + | pr27
pr2| + + + + | pr2 | + + + + | pr27
| + + + + | | + + + + |
| + + + + | | + + + + |
| + + + + | | + + + + |
| + + + + | | + + + + |
| + + + + | | + + + + |
| + + + + | | + + + + |
| + + + + | | + + + + |
| + + + + | | + + + + |
........... ...........
+=========+ +=========+
O I I O O I I O
Co Trunks Stations


So, you have your stations punched down on the outer pins of the
station block down both sides, and you have your trunks punched down
on the Outer pins of the CO block. You'd cross connect pr1 on the
Inner pin to say the Inner pin no the station block of whatever pair.

If this doesn't help, maybe the site
http://www.homephonewiring.com/blocks.html
can show you better.

[Retired]

Hello! On Pages C-2 and C-3 they describe how to make use of an
RJ21X connector and the 25 pair bundle and how to punch the bundle
down to a 66 Block termination array.
The illustration on C-3 shows one bundle punched down on the left,
and the same on the right. There are empty terminals in between
them.
Now the question, what happens when the installer needs to make
connections between the right and left handed bundles?
Yes I was asked this by a customer of mine several days ago. I
described what's seen inside the Leviton book, since (I hope) that
particular book is a part of most system installer's libraries.
The customer was watching me install a system that would make use
of one of the supposedly dead pairs on that bundle. ----- Gregg
gregg dot drwho8 atsign gmail dot com "This signature isn't here."

Use what are called "bridging clips"

http://www.amazon.com/Leviton-40067-BC-Bridging-Phosphor-Polybag/dp/B0009KIMXS
to make a connection from one side to the other

or punchdown a wire connecting the left and right pins if the
connection is not 1:1 between cables.