T1 Line Measurements in Cell Base Stations

If you are referrng to testing the copper T-1 used for backhaul, then the T-Bert is the name of the test set. There are several manufactorers of T-1 test equipment. It tests for signal level (Voltage Peak-to-Peak), frequency (1.544Mb/sec) BPVs (bipolar Violations), timing slips (if you have a timing reference), framing errors and if the line is optioned for SF or ESF and AMI or B8ZS.

I forgot to mention, if you put a known test signal ( all ones, all zeros, qrss, 3 in 24, 1 in 8 and 55 octet are a few I use) on the line it can test for bit errors.

Thanks

That was the info I was looking for. I wikid it and learned a little about it properties. I just wasn't sure if the testing was done on the line or the equip it is connected to.

Greetings! I'm a retired telecom engineer, and the lingo we used can be more than a bit confusing. First there are two families of test devices that essentially do the same thing but are spelled a bit differently. They are the T-BERT and T-BERD. Both are T-1 testers, either a bit error rate tester or a bit error rate detector. No real difference between the two. Original testers did only T-1 testing, but newer models will also test xDSL, DDS, some have TDRs, and maybe even some fiber optics test capability. To use one of these properly, I suggest you get acquainted with the physical parts of your T-1 transmission path, or you run the risk of making a small problem much worse. The physical path pieces include CSU/DSUs, fault locate filters, repeaters, etc. Learn enough about T-1 to know what AMI is, what loop up/down codes are, what the actual bit error rate is telling you (original T-1s only had to meet 1 error in 1000 bits, but today it is not unheard of to beat that by a factor of 1000 or more), whether your T-1 is std T-1, PRI ISDN or fractional T-1.

If you can get your employer to get you a copy of ANSI T1-403 (the T-1 spec), you will learn quite a bit about T-1. To really understand, and therefore quickly and accurately troubleshoot T-1 facilities, a thorough knowledge of AMI, B8ZS, ZCS, etc.(I'll leave these acronyms for your learning pleasure!) will greatly enhance your T-1 skills. Mac

Thanks Mac

I'll get to work on that. You've given me alot of useful knowledge and direction to look. I'll look in to getting the ansi spec.

thnks

J> floyd