sundance-communications.com/forum Forums General General Telephone & Systems Information radio interference

We use the Lucent Z300A.

Has always worked for us. One time I had to stack two back to back to get all the noise out.

But have had good luck with them.

You may also want to ground any spare pairs in each cable to the earth ground the telco uses.
Also, it may not be a bad idea to call the radio station and ask for their help.

We used to use a little white block made in Florida. We got them from Graybar, and they cost us about $15, as I recall. Can't remember the brand, but maybe this will jog somebodies memory. They were only good for AM, but they killed ANY AM problems! Sometimes, 1 at demarc and 1 at/in the phone, but they always worked. We had one so bad, you could pick up the station with a buttset with a 9 volt battery, NOT connected to anything. And not just in monitor. These things fixed it. As I recall the part number was PORFF.

Capacitor connected to ground and the line, I forget the size. I think .5 mfd.
Or Mike Sandman.com

Do you have the radio interference at the demarc? If you do, I'd contact the local telco. Have you tried a different type of phone. I've seen cases where one model picked the the radio and another didn't. Sandman has a good flow chart for radio interference. He also has different types of filters. You need to know if you're dealing with AM or FM.

Does anyone know where I can get some of the older 1542A RFI units. I have one but would like more of them to try eliminate AM RFI. I tried three of Sandman's AM RFI units. If I can't locate the 1542A units, I may try wire meshing the Partner cabinet. Has anyone ever tried the conductive type spray paint?
Thanks, DT

Target Distributing stocks them. They are the Suttle #SE-1542AM-50. Their number is 800-873-5528.

We've had a similar issue. We put in some kind of shielded cable and it has helped some. My wiring guys can take a toner and put it on any metal pipe in the building and hear the local am station as well. I get it in my headset on the switchboard console but I don't notice it through my handset.

A lot of good answers, let me throw in a couple of my own.

The 1542a was the filter we used in the Bell System days. A great product of Bell Labs Research.

Later, for LINES we got the Z100A filter from Bell Labs as well.

My preference would probably be the one I used first, the 1542a.

A word of caution about Ground Spare Pairs, it was our experience that if you grounded BOTH ENDS, you made an even better antenna.