T-1 Tester 1

[annacat]

Wondering if anyone has suggestions for T-1 testers. Looking at gl communications and acterna 2209, or others?. Want to try to determine strange problems (echo, dropped calls, locked channels, etc.)at sites between CLEC, ILEC, PBX. Anyone have pros and cons of these units
Thanks

 

[ISDNman]

If you are using PRI you'll need one that includes an ISDN (Q.931) protocol analyzer if you are troubleshooting dropped calls and stuck channels.

In that case consider the Network Communications Corp Network Probe. There are veritable swiss army knives. They come up on ebay periodically, you can get them often in the $300 to $500 range. Just makes sure they have the ISDN option (all units have the ISDN jacks so don't be fooled). The NP7300 always has ISDN. The NP7100 only has ISDN if it has the letter "I" at the end of the serial number.

These have extensive physical layer testing.

In the meanwhile you can do a lot of physical layer toubleshooting by

1) Substitute a smart CSU for the exisitng CSU so you can look at the error stats.

2) If the smart jack is actually an HDSL (e.g. HTU-T) or HDSL2 (e.g. H2TU-T) unit then you can use a serial terminal to get lots of information on the status of the system. Adtran has job aids you can get off thier web site that cover this.

Good luck

 

[annacat]

Thanks ISDNman, 1.We generally use the adtran csu ace (basic)units. What I need to do is connect into a network that has a problem without taking it down (which is what I would have to do if I wanted to temporarily put in a smart csu during testing). A lot of times resetting the T-1 or PBX clears the problem for awhile (sometimes months). Ideally I would like to determine where/who is causing the problem at the time it is occuring at various sites. I will have to look at the smart csu units to see if they would show enough info and what the price difference is.
2. I have connected into the 9pin connector on the smart jack and left pc onsite to monitor remotely via pc anywhere berfore, but Verizon tech didn't like seeing my equipment connected to their unit. I will look at the units you described and any others that are recommended. I saw a unit from gl communicatins that is an external box that connects to your laptop, it has a lot of features, but pricey.

 

[ISDNman]

annacat

The trick is not to get caught!

Actually you can connect and check all the error registers and then disconnect so as not to get caught.

I always check before calling them. That way if they clear the reigsters and say there were no errors I know if they are lying.

Intermittent problems are a pain!

You did not clarify if the problems are on ISDN lines. If so it you will get a LOT of data if you monitor continuously. A PC based system is beneficial there.

Be aware that if the pod connects to the PC with a serial cable you need a very fast connection or you will get bufffer overflows when the D channel is busy. It can get bursts up to 64 kbps.

Best of luck.

 

[Avidcomm]

Annacat
You might want to look at an Adtran atlas 550 it is a CSU/DSU/DAX with a lot of visibility. You can monitor The t-1 and identify which side the problem is on. you can Attenuate Line build out on the fly. You get alarms and stats from the last 24 hours. You can Install it temporarily in place of a csu or in line between Carrier and CSU. When it Burps I can see more than many T-berds will show.

 

[ISDNman]

For a really easy to use alternative to a T-berd the T-Com units are great. I believ ethey were bought up by AVO.

 

[SYQUEST]

One thing to be awhere of when dealing with any HDSL T1 is that the facility can go to pieces and you will never get any T1 alarms! And the only time you will get one is when a loop fails and the HTU-R loses power! Doublers can go to sleep, L1 or L2 can be shorted but as long as there is power you won't get a T1 alarm caused by the HDSL. I experienced these situations and more back in the 1990s working on T1s in Pacific Bell land. I'll take fiber or the old 'repeatered' T1s any time! HDSL is cheap!!! As long as the copper is good you won't have any problems.....

The utility might not like you looking at the error stack in the HTU-R, but they can't stop you. You or your customer are paying the bill for the ckt, so they really don't have any say, looking won't make a ckt stop working!

By the way, the ACE lock those mountings use, all use the same key, and you can get them from the suppliers anyway.

....JIM....