sundance-communications.com/forum Forums TDM Business Telephone Systems Vodavi Telephones & Systems Feedback issue on cordless paging

Lately, I have been having a real problem with Feedback anytime someone makes a 700 all call page from one of the cordless phones I have on my Vodavi DVX Plus II phone system. This is a recent development and am not quite sure how to handle it. I am using QTY of 2 VALCOM Model VP-2024 Power supplies to push my paging out to multiple POT controled VALCOM paging horns. One side of the building is on one Power supply and the other side is on another. Now, while I have the same paging output from the phone system connected to both Power supplies, one side of the building does seem much louder than the other which is where I think my main Feedback issue is coming from. This additional Power supply has been in place for over 4 years and has not had a feedback issue until this year. This only happens with cordless phones out on the floor, never from digital desk phones. Any suggestions on how to troubleshoot this?

Don't bother to troubleshoot it, just get rid of the feedback with a Viking feedback eleminator.
Part number FBI-1a.

Thanks for the advice Derrick! This should help a great deal.

In a non-telecom parallel universe, I am a musician... Feedback is caused when the business end of a microphone (or in your case, a cordless phone) is placed in front of, or 'pointed at', a speaker (in your case, a paging horn). The amplified output of the speaker feeds into the input of the mic which is sending its signal to the speaker to be amplified, and they continue to regenerate (very quickly) & get louder until you hear the screech. This becomes especially a problem when a person with a wireless mic (or in your case, a cordless phone)ventures out in front of the band, and the mic is unavoidably pointing right at the speakers. Ouch!

They may be able to get rid of the feedback by simply standing somewhere else when they page. Maybe they moved a desk or something, and the phone user is now in front of the horn??

I have also found that turning down the 'send' volume on a (digital or analog) cordless phone, even one single notch, greatly improves the feedback issue.

Of course, the feedback eliminator that Derrick mentioned (& I was not aware even existed) sounds pretty sweet, & simple to install/use. Unfortunately, sweet & simple usually cost money.

Thanks for the detailed explanation on Feedback GreggM. That's got to be one of the best explanations on Feedback I have heard. I had tried many of your suggestions already with not much luck. No problem. I just ordered the feedback elimanator Derrick suggested. Cool device. Hopefully, that will do the trick. Thanks for the good advice guys!