Interference on county fire

[Bullmax]

I am wondering if anyone can help me with interference on a couple of frequencies I have on my feed. These are the middlesex county fire ones. 154.7250 & 150.7250. Every couple of minutes I can hear whats sounds like static and almost like a radio station. Just wondering how I can fix it. I am using a 396xt and was using the stock antenna. I switched to the home made dipole antenna and it does give me better reception but now I hear this interference.

London EMS, Fire and OPP Live Scanner Audio Feed

 

[sirsmiley]

bad ground causing induction of the radio band? double check all your cabling and make sure the cable is properly shielded as well (quad shield rg6 or what not).

 

[Forts]

Are you using PL tones on these channels or just carrier squelch? I find that band is bad for getting trampled on from US stuff, which is why they changed the frequency from the old 154.3700 a handful of years back. Using the PL tones should certainly help.

 

[Bullmax]

Thanks for the replies.

Forts - Just using the basic squelch. I have no idea what you mean by PL tones. Is this a setting?

 

[mikewazowski]

I find that band is bad for getting trampled on from US stuff, which is why they changed the frequency from the old 154.3700 a handful of years back.

Wow!

The Simcoe County Mutual Aid frequency is 154.3700Mhz and I hear Michigan calls on it all the time.

I can't imagine how bad it must have been down in the London area.

 

[krokus]

Wirelessly posted (BlackBerry8530/5.0.0.973 Profile/MIDP-2.1 Configuration/CLDC-1.1 VendorID/105)

My guess would be cable TV leakage, possibly radiating from a TV or VCR.

 

[gary123]

most fire depts here use 107.2, the usa likes 136.5

 

[Forts]

Yes, it's a per channel setting. Try this: Spin the dial and call up County Tac 1 on your 396XT. Press E then scroll down to Set Audio Type and hit E again. Scroll to Analog Only, hit E again. The next screen will already have CTCSS highlighted. E one more time. Now spin the dial until you get to 91.5Hz and hit E. Do the same for County Tac 3. Basically what this will do is the scanner will ignore any transmissions on this frequency that don't use a subaudible tone of 91.5Hz. You should find it will dramatically cut down on the noise you hear.

Most conventional repeater channels use CTCSS or DCS (same idea, different format). You can look in the database to get these tones, or the scanner has a CTCSS/DCS search mode you can use to find them yourself.

 

[Forts]

Wow!

The Simcoe County Mutual Aid frequency is 154.3700Mhz and I hear Michigan calls on it all the time.

I can't imagine how bad it must have been down in the London area.

It was awful... I don't know how many watts St. Clair County puts out, but it would just trample everything in it's path around here.

 

[mikewazowski]

most fire depts here use 107.2, the usa likes 136.5

I think it's generally a radio shop standard.

One shop will put all it's departments on one tone while another shop will use another tone.

192.8hz used to be pretty standard in Simcoe County but over the years, almost every department uses a different tone now.

 

[Bullmax]

Yes, it's a per channel setting. Try this: Spin the dial and call up County Tac 1 on your 396XT. Press E then scroll down to Set Audio Type and hit E again. Scroll to Analog Only, hit E again. The next screen will already have CTCSS highlighted. E one more time. Now spin the dial until you get to 91.5Hz and hit E. Do the same for County Tac 3. Basically what this will do is the scanner will ignore any transmissions on this frequency that don't use a subaudible tone of 91.5Hz. You should find it will dramatically cut down on the noise you hear.

Most conventional repeater channels use CTCSS or DCS (same idea, different format). You can look in the database to get these tones, or the scanner has a CTCSS/DCS search mode you can use to find them yourself.

Thanks Forts, seems to have done the trick.