sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring TESTAR Adapters

Yes, you will notice the name of the product is TESTAR, not Telstar.

These are designed to be put on a block and TESTing the connection.

With a set that does not function properly, you can slap one of these of the distribution block off the phone system, and see if the set works there; then go to any sub-terminals, and test again, eliminating wiring errors all the way to the jack. The point of the wiring patterns has to do with the type of system you are testing. Merlins require the Testar wired 568-B, while typical 2-pair electronic phones need 2-pairs, wired Gree/Red/Black/Yellow. But when you run into an Intertel/Premier 3-pair, you need the 1st pair's polarity swapped.

I have several varieties in my test kit, all labeled for their use.

That name is deceptive.

Returning to the USOC/568A/568B subject, I may have misspoke.

For 568B, the color code is:
Jack pins 1+2=white/orange+orange=66 block pair 2
jack pins 3+6=white/green+green=66 block pair 3
Jack pins 4+5=blue+white/blue=66 block pair 1
jack pins 7+8=white/brown+brown=66 block pair 4

For 568A, the color code is:
Jack pins 1+2=white/green+green =66 block pair 3
jack pins 3+6=white/orange+orange=66 block pair 2
Jack pins 4+5=blue+white/blue =66 block pair 1
jack pins 7+8=white/brown+brown =66 block pair 4

For USOC the color code is:
Jack pins 1+8=white/brown+brown =66 block pair 4
jack pins 2+7=white/green+green =66 block pair 3
Jack pins 3+6=white/orange+orange=66 block pair 2
jack pins 4+5=blue+white/blue =66 block pair 1

Not 100% sure about the polarity.

As you can see above, all blocks are the same for pair 1. USOC and 568A are the same for pairs 1 and 2.

Point is that there IS a difference between 568A and 568B electrically.

You have to go by the part number:

• Testar 8 = 568B
• Testar 8T = 568A