atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services T1's, CSU's and DSU's T1 Yellow alarm

I am having a problem and I'm not sure if it's my cross connects or a hardware problem. Here's the configuration,,(Customer Prem)Router(T1) --> DS3 Mux --> Router.. At the Cust Prem I came out of the serial port on the router into an 8 pin Bisquit.I used Pin 1(Bl/Wh)..Pin 2(Wh/Bl..Pin 4(Wh/Or..Pin 5(Or/Wh)-->200' Cat5e cable to another Bisquit..Then used a patch cord into the NIU..I am receiving a yellow alarm at the Customer Prems Router. I wanted to make sure my cable connections are not initiating this Yellow alarm. Any ideas? Thanks

On one customer site with prob. I made loopback plug for t1 router,then called vender{AT&T}to have them look for return signal,it was ok there so i moved plug to end of wire cat5e and tested again by calling vender,again ok.Customer router was the problem.------------John

Good advice, just loop your equipment back to itself at the last point before the LEC. If you sync you're good, if you get AIS (red) you're connection is bad some place, just keep working back until you find it.

You receive a yellow alarm when the far end does not see your frame signal. One simple check is to take jacktels advise, put a loop on the ckt at the NIU and ask the carrier if they see it. If they do move the loop to the extended jack and test again. Another quick check is to change the framing on your equipment; both ends need to be using the same framing sf or esf.

Yellow alarm means the far end is not seeing your transmit signal. You are receiving OK. Check your wiring, make sure it's straight through all the way with a wiremap test if you have a cable scanner.

Check the RLOS LED on the smartjack, but don't trust it 100%. RLOS typically goes out when the NIU sees the CPE. However, it only needs to see one wire of the pair to go out.

Take a banjo and a multimeter. Plug the NIU in, test from the far end. You should see about 10 ohms resistance between pins 1 & 2. Check again on pins 4 & 5. You can plug the CPE in and test from the other end as well.

Somewhere in there you mention 200 feet of Cat5e cable. Might try changing any gain settings or Line Build Out at one or both ends....