Re: Type 66 Block

[Lewis Gardner <lgardner@xxxxxxxxxxxxxxxxxxxxxxxxxx>]

> My question is this - why would someone use that
> method (looping your way down the block to distribute
> to multiple locations) instead of a bridged 110
> punchdown module. such as this one -
>
> http://www.hometech.com/techwire/lvtp.html#LE-47603110
 > ...
> Can you shed any light on why my method may be wrong
 > or what the advantage is of the 66 block besides
> being able to pull the jumpers to isolate a line?

The problem with these "bridged" type blocks is how they are
implemented. If you refer to the above drawing you will notice that the
station wire going to the jack is punched to the bridged block. This is
only useful in the most simplistic installations. In the drawing there
is a fax. If the fax line is line 2 then either a special line cord,
single line jacks or swapping pairs at the punchdown would be required
to connect the fax to the proper line. The same problem would present
itself for office or kid's phones that came in on lines other than line
1 and needed to be connected to single line phones or other devices.

The whole idea of punchdown terminations is to terminate all the station
wiring in a logical and permanent fashion while allowing easy Moves,
Adds and Changes. The proper way to utilize a "bridged" block would be
to terminate all the station wires on standard 110 type blocks and then
crossconnect to a bridged block.

For me the easiest way to handle phone lines is illustrated in these links:

hi-res
http://xs.to/xs.php?h=xs30&d=05214&f=phones3.JPG
http://xs.to/xs.php?h=xs30&d=05214&f=phones2.JPG

low-res
http://www.pix05.com/t/phones16129.jpg
http://www.pix05.com/t/phones26294.jpg

Four lines enter from the NID in the four port surface mount box at the
top center and are broken out to single line jacks. From there line 1
goes to a DSL filter and on to the DSL modem and the blue pair on all
the regular station jacks. Line 2 is the fax line and goes to a Stick
http://www.multi-link.net/products/stick.asp and on to the center pair
at the fax and modem jacks. Line 3 is a rollover from line 1 and goes to
the orange pair on all the regular station jacks.

At the station jacks the blue and orange pairs are terminated the the
left top jack and the green and brown pairs are terminated at the top
right jack.

I find this method to be fast, easy and simple to understand. Any
configuration of line X on pair X can be implemented easily and without
disturbing the permanent wiring. If the customer decides to upgrade to a
phone system that can be done without disturbing the permanent wiring.
If you need to convert the phone wires to network wires (VoIP) then all
you need to do is rewire the wall plates. If you look closely you will
notice that the wires at stations 14-17 are not punched down so those
jacks are not "hot" but ready to go. Easy and flexible.

The only advantage of 66 blocks over this method is the ability isolate
individual station jacks by removing the bridging clips. This is fine
for "phone guy" types but I don't want to have to go onsite to solve
that sort of simple problem.

The troubleshooting method I usually employ is:

1. Unplug the jacks at the surface mount box above the 110 block and
check for dial tone. Sometimes you have to wait a minute or two for dial
tone to return if there is a defective phone. No dial tone = check at
NID and usually call the phone company.

2. If dial tone returns with the 110 block disconnected then I have the
customer unplug all the phones and other devices from their wall jacks.
Reconnect the plugs to the surface mount box above the 110 block and
check for dial tone while reconnecting each phone one at a time. Usually
when one of the phones is reconnected dial tone will drop and that phone
is defective, usually the victim of lightning.

3. If all of the above fails I will go and troubleshoot. This is almost
never required. Even if I have to replace the loop wires on the 110
block it takes at most 10 minutes.


My feeling is that 66 blocks are an "old" technology that cannot meet
current specifications for twisted pair installations. Not really a
problem for POTS (Plain Old Telephone Service) but if you have installed
cat5 or better cable why not terminate it in the best possible way?


Caveats:

Not installed (yet) in the picture is a surge suppressor that will be
mounted to the right of the surface mount box.

DO NOT use stranded wire on punchdowns. Stranded wire may work for a
while then cause problems.

When crimping plugs onto solid wire BE SURE the plugs are designed for
either solid wire or both solid and stranded wire. Close examination of
the plug contacts will show either or both a "spike" for stranded wire
or a "saddle" for solid wire.