atcomsystems.ca/forum Forums TDM Business Telephone Systems Avaya - Lucent Telephones & Systems loud buzz in Partner 18d phone

I am having a bear of a time trying to troubleshoot a buzz on my Partner 18d phone. I just installed an ACS 7.0 proccessor and have 4 phones installed on the system. The wiring is cat5e cable and was installed throughout the house during a recent rehab. Two of the phones have no problems. The third phone has a slight but annoying buzz. The fouth phone has the worst buzz, Very Annoying. I have done various swaps with each phone to see if it is a phone problem. Every phone I put on phone line #4 has the buzz on it. I take the phone down to the basement to the ACS and plug it directly into the unit and the sound is clean, no buzz. So, obviously it's in the wiring. I "assumed" that cat5 cabling would be a good choice for any emf issues, I guess I am an "ass". Anyway, after many hours of frustrating troubleshooting I am at a loss on how to get rid of this buzz. Before you ask, it is difficult to run any new lines to this part of the house without breaking walls. I already have a second cat5 cable in the same wallbox but that does the same buzzing. I was wondering if the was some kind of a choke that would work.
Any thoughts would be appreciated. Dave

Sounds like EMF to me, especially since you said you've used a different cable same results. Assuming there is no physical cross between the talk path and the data pair, kill the power at the breaker panel except for the phone equipment and turn them on one at a time until you find the one causing the problem. Then you'll have to work on those outlets/lights to see which ones causing it. Normal house wiring shouldn't cause this and I'm assuming you know the phone is not close to anything that would cause it. There are chokes, but this problem should be fixed if possible instead of covered up. One thing on EMF the longer the wire the more the noise, so the source could be anywhere. So make sure you don't have anything close to the KSU that could be causing this also. You may try grounding the unused pairs also, but this probably won't fix it.

Before you condemn the wire have you got the pairs correct and the jack wired correctly? How have you got the "CAT5" connected to the port on the ACS?

Now I'm a little confused by- Every phone I put on phone line #4 has the buzz on it.

Are you saying that if you pick up CO line 4 on phones at these two locations you hear a buzz but you don't hear it on lines 1, 2 and 3? Also, when you plug a phone directly into those same extension ports on the ACS there is no problem?

-Hal

I assumed he ment the 4th station port. I also assumed correct wiring with no crosses. I know what assuming does and it won't be a first.

Make sure it is 568B --- and justbill is correct about the grounding of unused pairs. This is "ass-u-me"ing it is on a block and cross connected -- not with a plug crimped on the end.

If both cables are "humming" the power issue that justbill suggested will assist you in finding the problem but if the wiring is not properly installed it will not help you much. Not run in the same holes drilled for electrical, run over lights with ballasts, or pinched / in tight turns.

Good luck,

KLD

Exactly. Usually problems like this are not caused by the wire itself unless possibly it was skinned or nicked and grounded somewhere.

I had a problem like this once that was caused by a cat urinating on the jack.

I would be almost positive that this is not an EMI problem but rather something you did.

-Hal

I'm guessing that it's not wired 568-B or even USOC 2-pair, and you're hearing the "data" on the 2nd pair bleeding into the voice pair.

Y'all are probably right about bleed from the data pair. I'd think if it were EMF he'd describe it as a hum more than a buzz. Guess I'd have to hear it to know. One thing if he kills the AC he'll know for sure, especially if he has a UPS on it to isolate all power. I've only had one where the data pair was interfering it was obvious and I could see a cross between the pairs.

Right. The cat urine left a residue in the jack that bridged the data pair and the T/R pair with enough resistance that the data bled over to the T/R.

-Hal

Hey guys thanks for the replies, I didn't explain my system enough to you before so I will correct that now. I am a facilities manager and am pretty competent with the Partner Phone Systems. The house that I installed this new Partner ACS 7.0 houses 4 priest with seperate private lines to each suite/bedroom and also one phone in the kitchen. They all have their own private number and line. Line 4 is the one that is giving me fits. I have taken the phone from the problem wall jack(#4) and plugged it in directly to the ACS downstairs. There is no buzz on line four at that point. Line 4 is used strictly as a point of reference. I have swapped
all the phone company lines with this cable going to the problem wall jack and the problem does not change the buzz/hum stays no matter what phone line I put on the cable.

I did some more troubleshooting today and ran a new cable, Cat5, thru the house directly from the ACS to the phone jack. The buzz was not there. Which of course tells me there is a problem with both cat5 cables in the wall. I stated in my first log that it is difficult to run a new line through the walls with out major wall holes. The house was rehabbed in the last year and is looking pristine. Is there any thoughts on using the existing wires. Thanks again for the responses. Dave