T1 running hot

[namesrhard2pick]

Anybody body hear the phrase T1 running hot and need to be padded? Refers to T1 being very sensitive to noise, etc. I had some new PRIs installed by Paetec and I am having some issues. Paetec engineers suggest the PRIs are running too high and should be padded.

 

[SYQUEST]

How do you have the equipment configured? CSU / SWITCH / IAD?

What distances are the cables?

Are you using the proper DS1 cables?

You do need test equipment like a T-Berd to measure levels and run tests.


....JIM....

 

[skip555]

sounds like typical CLEC BS

so isn't it Paetecs responsibility to correct it ?

 

[SYQUEST]

Well, until you have known values to present, etc. how do you know they are hot? Since Paetec mentioned the possibility, I would put the pressure on them to send their tech to the site with the appropriate test equipment. In addition to the items I raised above.

....JIM....

 

[pbx2sip]

Can you give some better details as to what you are talking about. Sensitive to Noise? Are you saying on a phone call, the phones are sensitive to background noice, echo, clipping, or what?

How are the T-1's terminated. Does Paetec provide the termination to an IAD, or do you terminate them on a local CSU? If they say padding is needed, then they must know what they are being delivered to you at, what DB are they being dropped off at? Or are they just guessing on the issue and have not done their required testing.

Any carrier that is credible, should be able to put a meter on the end of the T-1 and provide the engineering specs, and make test calls without this noise they blame on a lack of padding.

Get all the liars in the same room - and talk about the issue - without all the facts, your only guessing as to the issues, which could be many.

 

[4946]

namesrhard2pick,

The running hot reference usually means that either the circuit level from the carrier or from the switch is being delivered with too high a db level for the particular installation. Most of the time if the levels are too high you will have echoes on one side of the conversation or maybe both. If you are experiencing noises, popping sounds, or static, there may be a timing issue between the switch and the circuit,or the levels may be too low.

If you can adjust your switch circuit interface, first make sure that the timing for your switch interface is set to clock off of the incoming circuit or another incoming circuit if there is one already in operation. Then set your line levels for the problematic circuit to 0db, and work down in the settings to see what effect that has. If your switch does not have the settings in db, it will probably refer to line length, start with the longest line length and work down.

Hope this helps

 

[SYQUEST]

We are talking about two different levels here!

You have the DS1 (digital) level and you have the levels of the individual channels. They are distinct and separate, and to identify them or the equipment used would be one way for us to intelligently discuss what you have @ hand or what the problem is...

....JIM....

 

[donb01]

This is a question coming of of my own not knowing, and not a statement of advice - I'm hoping to understand better...

On the T1/PRI circuits I use I'm familiar with the loop length/attenuation switches/jumpers that are usually associated with the CSU and/or smart jack for the level of the whole circuit, but unless you are using a channel bank how much control do you have on the individual channels? I know in my Siemens stuff when I configure a trunk (which would be a B-channel in this case) there is a parameter for attenuation type, but that is pretty much a one size fits all setting (either CO or TIE in my case) for this kind of stuff. I wasn't aware there was any more adjustment beyond that??

 

[SYQUEST]

donb01.

Typically, that is the case the "audio" levels are fixed for the channels on either end depending on the equipment provided or used: PBX, MUX, IAD, or DACS. Everything is at unity gain. But some manufacturers provide some padding or other programmable adjustments. In the case of a channel bank, the levels are left to the channel units to make the appropriate level sets between the analogue and the digital. They all have their specific operating levels.

Unfortunately, I have seen folks confuse the DS1 (the pipe) digital operating levels with individual channel levels. I don't think they understand or see the difference because the term "dB" is attached to both types of specifications and not having a channel bank, don't realize things are done in a codec or software these days. Sometimes the manufacturer's documentation or description is not as clear as it should be. So when folks read it, they are confused or get a different picture of reality.

Hope this helps!

....JIM....