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66 Block Wiring - Need Help Now!

I'm, for the first time installing a punchdown, as I have a new phone system, and need one.
I have the manual to the pbx, and it shows me the pairs, and where to punch down the 25 cable.
My question is, where on the punch down do I punch the incoming lines and the jacks for the extensions.
Im assuming across from the pair of wires on the 25 cable that correspondes with line 1, line 2 etc.
My problem is, which clip, the second, third or fourth clip? I've read about bridge clips, and just dont really understand. Any help would be nice!
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1 Solution
a 66 block is nothing more than a conductor block for the incoming receive (R) and transmit (T) pairs from both the PST (POTs lines) and the internal telephone wall jacks.  On a 66 block by convention the left side of the block will contain 2 jumpers.  One for Receive and the other for Transmit for the incoming POTs line.  There are at least 2 ways to do this, however I find that the best way is done without the need for bridging clips.  I will try to draw a diagram below:

    PSTN    Wall Jack
         |         |
         |         |
        V       V
          -       -        <--- Blue Stripe
         +       +       <--- Blue Solid
          -       -        <--- Orange Stripe
         +       +       <--- Orange Solid
          -       -        <--- Green Stripe
         +       +       <--- Green Solid
          -       -        <--- Brown Stripe
         +       +       <--- Brown Solid

From the diagram, you can see that in this case, the 66 block is punched "downward"  The left column is used for punching down PSTN (POTs) lines and the right is for its corresponding wall jack or FXO port or device such as alarm system, paging system, credit card machines....etc

Consider for a moment just the "Blue" pair going downward, you have to punch the "Tip" or positive (blue w/white stripe) in the first column and just below it, the negative or the "Ring" with (negative) again under the 1st (or PSTN) column.

Just next to each of loop conductors, punch down the corresponding wall jack extension in the same polarity (positive for positive, negative for negative (or tip for tip and ring for ring...etc).  The 1 caveate I'd like to explain about the extension side is that you'll have 4 pairs (using cat 3, 5 or 6 cabling).  I typically use the same pair as I would the PSTN side...so that if I used the blue pair on the pstn side, I use the blue pair to correspond on the wall jack side.  this allows the blue pair to be punched onto a wall jack at the end-users office.  If they need 2 jacks, then use the blue first, then the orange....and so on....but make sure to punch them down onto the appropriate PSTN pair.

This will complete your full duplex loop on 1 circuit.  Follow the same methodoology for the orange, green and brown pairs in that order as to follow ITU standards...If you have more than 1 cable (4 pairs) then repeat the color order from the top and keep looping until all is complete (blue, orange, green, brown...repeat....repeat...etc)
This should get you more than started.  Let me know if you're unsure of anything at this point.
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