Radio bleedover

[Stephanie.]

Hey everyone,

Was wondering how many other agencies have issues with radio bleed over from other services. One of our fire channels is constantly getting tone outs from a service several counties away. Its really annoying, but I guess the only way to fix it is to reprogram all the radios and change channels. Bummer.:wacko:

 

[abckidsmom]

We have a school bus system in Maryland. "HEY BOB? Can you head over to route 72? Jenny was late again this morning."

It's pretty annoying.

 

[nakenyon]

Not so much now that we've gone to a P25 system. But in my county (Dauphin PA) we used to get a lot of bleed over from Adams County EMS.

 

[Stephanie.]

Yea one of our tactical channels gets CB bleed over.. Bubba is always lost on these backwoods county roads.

 

[yyc_ranger_4x4]

I don't believe that your dept's would have to change complete channels as getting frequencies is hard enough as it is, rather put a tone on the channel. What this does is your radio could receive a transmission let's say 462.675MHz, but unless it's also getting the correct tone, then you wouldn't hear anything. The tones are inaudible, and there are also some digital codes that act the same way depending on the radio's used.

I've programmed many radio's this way to stop this kind of bleed over. Frequencies are usually shared, but usually they are given out to areas that shouldn't overlap. But it happens. I know that alot of services don't like using tones, and I never could figure out why.

 

[socalmedic]

we do, actually a company IN THE SAME COUNTY (Los Angeles is kinda big) has the same Fq that we have. usually no problems, but if it is overcast we can hear them clearly, something called atmospheric propagation or so i am told. this will resolve next year when we change to a digital trucked system. but untill then there is nothing we can do.

 

[eynonqrs]

Many Factors here.

There is many factors for bleedover:

All radios have PL tones. In order to not hear the bleed over, your radio should be set up that the PL is on TX and RX. We have the same problem in my neck of the woods. The county Fire CH had to go to PL being that we heard Broome County NY fire. Also for my private service that I work for, our dispatch channel is also a ch for Monroe County, we have PL on TX and RX and we can see the id come across our screens from Monroe County. Our VHF channel is shared with a school district. And yes, when the bands open up, you can hear other services, hundreds, maybee thousands of miles away, especially if on low band [33 Mhz area]. There is not much else you can do. The bands are crowded. It's rare that you can get an exlusive channel. The problem with digital is that your either heard or not heard. Kind of like DTV that was mandated, you get the signal or you don't. Trunked systems are good for flat end areas, but if you are in the mountains, you will get dead spots. Remember the higher the frequency the more "line of sight", lower freq tend to bounce off the atompshere. You have a better chance of hearing other service far away on 33 Mhz than 400 Mhz.