1

66 blocks are prevalent in the telecommunications industry

Today they are used primarily for phone applications only

BASIC TELCOMMUNICATIONS 66 BLK

66 block

2

There are many variations of 66 blocks we’re going to focus on the two most commonly used type of 66 block which is the 66B for CAT 3 and 66M for CAT 5 applications

BASIC TELCOMMUNICATIONS 66 BLK

3

The 66B/M is a split block that provides the capacity to terminate a 50 pair cable or (2) 25 pair cables or (12) 4 pair cables

BASIC TELCOMMUNICATIONS 66 BLK

4

66 blocks come with a separate mounting bracket that is labeled for a specific orientation

BASIC TELCOMMUNICATIONS 66 BLK

5

The 66 bracket provides a stand off from the back board so that cables can be passed behind the blockThe openings on the side are provided to route cables and pairs from behind the block up to the termination point on the face of the block

BASIC TELCOMMUNICATIONS 66 BLK

6

Here is an example of 4 pair cables fanned out from the sides of the block and terminated on the front of the 66 block

BASIC TELCOMMUNICATIONS

7

All multi-pair cables are terminated on the first row of a 66 blockThe adjacent column is used for cross wiring.

BASIC TELCOMMUNICATIONS 66 BLK

8

Here is an example of cross connects between 66 blocks, note the wires that are stretched diagonally across the blocks that is an example of what not to do.

BASIC TELCOMMUNICATIONS 66 BLK

9

We are going to build a link similar to the one below, however we will concentrate on only the wall jack to the 66 block by the end of the course we will install this same system from beginning to end.

BASIC TELCOMMUNICATIONS

10

You will mount a 66 block on the backboard and run a quad cable to a biscuit jack also mounted on the backboard.

BASIC TELCOMMUNICATIONS

11

Any time you terminate a communications cable onto a screw terminal device in the telecommunications industry it is automatically considered a category 3 device

As you recall a POTS line is considered category 1

We will go through the steps of terminating a POTS line onto a CAT 3 jack and the other end will terminate to a 66 block

BASIC TELCOMMUNICATIONS

12

Components and tools needed for wiring a basic phone link:

BASIC TELCOMMUNICATIONS

13

Preparing the wire ends for termination onto screw terminals

It is important not to wrap the wire around the screw, it will break when the screw is tighten down

CORRECT INCORRECT

BASIC TELCOMMUNICATIONS