Networking Volume Problem! 2

[killbox]

Has anyone encountered a volume problem on 2 networked magix systems over a point to point T1? I believe they're release 2.0.

Scenario
All calls come through point A over pots lines. When calls come in, they're either transfered by the reception or auto attendant. When the call is on point A the volume is fine, but when the call is transfered to Point B, you can here them, but Point B can barely here caller. I've had telco there, and I'm 99% sure it's not them.

Should I upgrade them to 2.2?? Should I swap the processor out on the low volume side or swap a line card out at Point A side? People I know heard of this, but don't know a fix or a cause.

Thanks,
KILLBOX

 

[merlinman]

No, I do not think so.

Let's re-examine your alphabet.

Point A is the ORIGINATOR, Point B is the place that POINT A Calls and POINT C is the end point that receives the call, FROM A thru B to C.


I think it's like this:


A - - - - - - - - B - - - - - - - - C

Caller - - - - MAGIX 1 - - - - - MAGIX 2

So, you are faced with the TOTAL LOSS of transmission from A to B - THRU B - and from B to C.

These things are measurable (if you have the right stuff)

Transmission loss is expressed in DB's the higher the number, the lower the volume.

In a nutshell, here's how it happens.

A to B (on a good day) Should only be about 4 DB (Decibles).

Thru B (Loss in the Magix) can be up to 2 DB.

From B to C is again, about 4 DB.

(But these values are not always that GOOD, sometimes they are GREATER, NOT GOOD)

So, the caller at A to B hears only a 4DB LOSS, but all the way to C it adds up to about 10 DB. QUITE A DIFF !

The most likely suspect is the Loop Start Lines.

Not that you can fix them, you see, but you have to insure that you are not adding to the loss, with REVERSES and stuff.

Changing the HARDWARE or softare versions most likely will not have any affect, but you may be able to tweak the "LINE COMP" under LINES/TRUNKS, TT/LS/DS1 (SLOT NUMBR) and see if that helps.

It might.

But then again......

(It starts at 1 and you can bump it to 5, but TEST IT to see what affect it has.)

Of course, your vendor may be able to help you if they can do an overall transmission loss measurement.

But then again......

 

[killbox]

It's only 2 magix's. When a call comes in on the pots lines at Point A and then gets transfered to POint B, Point B can barely here the caller. I'm the vendor for this. I took this account on. How do I tweak that DB in Line Comp??

Point A <-> Point B

Networked with a point to point T1.

Thanks,
KILLBOX

 

[jinxs]

Killbox, is there low volume with inside calls over the UDP? What is your line comp setting under LS/GS/DS1? This is the comp between the switch and the CSU/DSU. I don't think that would matter all that much but it is something to check? If your CSU is between 1-133' is should be set to one. As well, what is the distance between the two facilities? Is your switch settings correct? If you do a print of the General trunk set-up, it would be the last colum. They as well should be different between the two switches? Just some food for thought.

 

[killbox]

Hey, they're only about a mile apart. Intercom calls are fine. The line comp is set to default on both sides.
Switch settings? What should they be??

KILLBOX

 

[merlinman]

Again, you are looking at the loss from B to C, not A to B to C. Right?

They start at 1, I'd just experiment and see what happens with each different value. They only go from 1 to 5.

I gotta go eat turkey now.....

 

[killbox]

From Telco (A) to Point A (B) it's fine. Only when it goes to Point B (C) where the loss is.

 

[merlinman]

Yes, but isn't (By my Alphabet) B to C OK as well?

Again, I think you are seeing the result of the ACCUMULATED LOSS, 4 + 2 + 4, or more, once they all get added together.

 

[jinxs]

you switch identifers are as follows:

1-20 Legend/magix to legend/magix more than 200 miles away
21-40 Legend/magix to legend/magix less than 200 miles away
41-50 legend/magix to non-legend/magix more than 200 miles away
51-60 blah blah blah less than 200 miles.

where do you change these? good question.

sysprogram-->exit/start-->lines/trunks-->more-->udp-->trunk number-->and I think you can figure out the rest.

As well, they need to be different at each system. Normally 21 and 22.

Good luck

 

[killbox]

MerlinMan,
What do I do to compensait this.

Jinx,
Well it's less than 200 now. They're at 21 and 22. What should I change them to? What is this doing actually?

Thanks,
KILLBOX

 

[merlinman]

OK, we are kinda' talking about 2 different thnigs. I was talking about what JIJNXS was when he asked &quot;What is your line comp setting under LS/GS/DS1?&quot;.

Like I said, I'd play with it. Again, starts at 1 goes to 5, with 5 having the most &quot;COMPENSATION&quot;.

I can't gaurantee it'll fix it, after all, your tweaking something that in theory shouldn't be tweaked.

But I think its worth a shot.

Of course, you can always ask the T&R Vendor to give you TRUNK CLASS Service which in the &quot;OLD DAYS&quot; meant you were gauranteed 4 DB's or less on those kinds of trunks.

Heck, you may have 6 to 8 Db in there now.

 

[jgideon]

Killbox:
I'd bet they have the same volume problem if point A conferences two outside lines also... sounds like classic trunk-to-trunk low volume. I can't speak to the compensation options discussed above, but if that fails, maybe you can convince them to put in a T1 card--if you're going all digital into pointA, you shouldn't have any problems.

 

[merlinman]

I agree, ALL DIGITAL is better.

 

[killbox]

Well, they only have 7 pots lines in A. They won't change to a T1. They don't like change. I've already tried.

Now I'll try and go into the line comp and bump those up. What about the switch settings? I have 21 and 22 now. Jinx said they go from 21 - 40. What does this do for me? I've never got too into these.

I've had telco out there a couple times now. When they test at the RJ, the test fine. They tested DB, grounds, etc. No problems and all lines are fine. Conference on the 1 side is fine jgideon.

Thanks,
KILLBOX

 

[jinxs]

Your on the money with your switch settings killbox. No need to change those. You could change your line comp...maybe it will help. The Network reference said to change to an all digital facilitie. No help there with your case. DO you know what the co measured your lines at?? They are allowed up to 8db without having to make a change...unless you are in Canada which I don't know what is and isn't allowed up there. I know you can buy attenuaters from Sandman to lower the db level. good luck.

 

[merlinman]

KB, to tellco, almost anything is fine.

Get them to tell you what &quot;FINE&quot; is.

-6DB, -10DB or WHAT

I would almost bet they don't have a clue about what a DB is.....

 

[SYQUEST]

Hi everyone,
Interesting subject matter! The line compensation you are discussing has to do with the T1 only! This equalizes the T1 waveform to match the cable length between the CSU module and the Telco NIU. That is all it does! It has NO effect on anything that 'rides' the T1 facility. T1 is essentially a lossless medium, being in the digital domain. Now the level issue seems to be concerning the local analog loops. This is probably were your problem is. You say Telco came out and tested the lines. What measurements did they perform and what were the results?.. Anything longer than a -4.0dB can be a problem in this type of setup. The losses are always additive. If that is the case there are alternatives. Not knowing the loop makeup or the service provider, I would have the lines changed to PBX class of service and request that VF repeaters be added to the loops to get levels of -3.0dB to -3.5dB at the MPOE or demarc terminated at 600 ohms. If this is not an option then you could have a local T1 put into the system and the lines moved to it, but you mentioned they only have 7 lines so that might be hard to cost justify. Do they have any data ckts presently? It is possible if they have a T1 for data that was not completely used that channels could be used for voice and split off to the Magix to a DS1 module? If so that is something to try.

Another option is changing service providers. Alot of CLECs these days bring the service in on a T1 and mux it to analog at the prem so you have minimal loss at the MPOE or demarc.
This could be an advantage to force the LEC to 'put out' or you go to the competition for better service!

One last suggestion would be to add VF repeaters at the prem. There is a company that makes this type of device but I will have to get back to you with the info as I don't have access to it at the moment. Teltrend used to make one but that product got sold to another company. That's what I have to find.

Hope this helps!

....JIM....

 

[killbox]

I was away for a couple days. Thanks everyone for the help! Ok, I definetly would like to get the info on the VF Repeaters because I have a customer that has some real bad luck with this system in the past, and bad luck with carriers. They just changed from the LEC to a CLEC (Verizon to Conversent). They just brought it right in over Verizons facilities though. They no way will change again and spend the money for a T1 card. The only choice I have is to fix this problem myself somehow. What a disaster!

So, my switch settings are fine, and I don't need to change the line comps. I guess my only resort now, especially with this difficult customer, is to get the repeaters.

Just a small bit more of info. I found out that the previous vendor swapped out one of the processors because the T1 card was reseting on its own and this fixed it, but it didn't help the volume. Also, the side that is the far end, where the volume problem is, they were hit by lightning 2 years ago and the T1 card had to be replaced.

Thnaks,
KILLBOX

 

[SYQUEST]

Hi KILLBOX,

Sorry for the delay, the company that makes the loop repeater is ENGINUITY COMMUNICATIONS @ 800-980-3266, on the web

http://www.enginuitycommunications.com/

The repeater is called the CYBERBLOCK LR4002 series. They have an engineer that you can talk to about your application. This was originally a TELTREND product, then WESTELL acquired TELTREND and spun off several products to ENGINUITY, the CYBERBLOCK was one of them.

Did you ever find out the level loss on the local loops? Before spending anymore of the customer's money I would really lean on the CLEC to get the levels up to where they should be. I would think that the CLEC has a colocation with VERIZON and the lines are connected to a channel bank or mux at the CO. The channel units have level adjustments on them or are programmable via software. So there is NO excuse for bad transmission levels at all!! If you don't get cooperation from the CLEC repair after escalating up the ladder, I would contact the state PUC to get involved and have some sort of resolution. Sometimes you have to go to this level to force some action for your customer.

One last thing, not knowing the 'make up' of the local loops, are these pairs 'loaded' or do they have any 'bridge taps'? Load coils improve voice transmission on long loops and bridge taps can act like capacitors so to speak.

Hope this helps!
....JIM....

 

[killbox]

Wow! Thanks for all the info. I should be working on this after XMass. I will hound the CLEC on the DB loss and what not. If all is good though, I'll look into the repeater. Now as far as long loops or bridge taps? I don't know what this is? I actually have 1 of the &quot;SideKick&quot;'s that verizon uses to test pots lines, but I don't know how to use it. If I did, I'd test the DB myself.

Thanks,
ALex