Talkgroup 50480 (WC Fire Ops 35) Background noises

[KA9AHQ]

Washington County
I hear in the background machine like noises squealing ?, sometimes almost like shaking a tray of broken glass.

Also on 63888 (WC SO Tac1)

Any Ideas on this ?
Its popping up on some others.
I have moved the scanner (pro 2050) I still hear it.

tnx
73 de KA9AHQ/7

[PMJ2kx]

I've heard it intermittently on all Ops channels, including dispatch.

There's also a whining noise from time to time (not the normal one from the engines, mind you).

[pdxbofh]

I assume you are not talking about feedback.... The fire folks don't use ear pieces like the most of the cops do, so they tend to key up next to each other and give dispatch a nice ear-full of feedback quite often. That's the only thing I can think of.
WD
Ke7LRB

[Fix_It]

I'll assume you are familiar with the buzzing sound that any modern cell phone or nextel unit can introduce into an audio circuit and that THAT isn't what you are hearing. That can be introduced into a microphone audio circuit during transmission from a field subscriber unit. I have also heard it being introduced on outbound transmissions, presumably from a dispatcher's personal cell.

Now, if what you are hearing is truly "in the background" as you say, then from the description of "a tray of broken glass" could it be tire chains while a mobile unit is in motion? I must say I've never heard anything on the air like what you said, but lastnight when I heard an officer going as fast as he safely could to a call, I did hear a similar sound and I am certain what I heard was chains.

A mystery!!