Noisy Phone

[silver987]

I have a customer with a MICS 7.1 & CP100 3.1. Two phones in a shop area with 2 desks and 1 T7316E on each desk. There is a loud buzz on both phones, I put a long cord on the phones and moved them away from the desk area and the buzz quit. Does anyone make a filter of sorts? I know they are not going to move their desks. I said I would research the problem.
Thanks for any suggestions.

Wayne T

 

[misseditbythatmuch]

I would suggest further review of the potential source of the noise. Is there a fluorescent lamp with a dying or old ballast in close proximity to the phones? Is there an old CRT on the desk near the phone? Is there a power feed laying next to the regular line cords? If there is a space below them, is something mounted to the ceiling below that is electrically noisy?

What and how you filter will be based on the type of source. I have seen induced noise as the result of a dying CRT acting on the handset cord as an antenna. I have seen line cords parallel to large amp draw cabling that induced noise that needed shielding more than filtering.

At the risk of being too commercial, I will add this link to some good devices and a thoughtful write-up and diagnostic flow chart. It covers both CO lines and Digital KSU/PBX lines.

http://www.sandman.com/rfbull.html

 

[silver987]

Thanks for the info. It's a lot to take in...But I really appreciate it.

Wayne T

 

[ironhorse17]

Had some with long handset cords picking up interference from lights, switch to short handset cord.

 

[allworxguy]

If you can't eliminate the source, you can try wrapping the line cord around a ferrite donut.

Marv

http://www.telemarv.ca

 

[joelunchpail]

how many conductors in the line cord.
check the jack to see if there is a connection to the second or third pair.
or just use a 1 pair line cord.