CloseCall range

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arctic

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I have tried to test the range of CloseCall on my new BC125AT by using a FMR UHF radio.I found out that the detection range is around 10 yards for 0.5 watt. I then got my 5 watt 70cm ham radio, and the range was now around 20 yards. My BCT15 x has a range on UHF on around 40 yards for a 5 watt handheld. I know that CloseCall works OK on my BCT15x, after all it detects aircraft in the AM 118-136mhz band a mile away. But after the UHF test i am wondering what the range is on the police VHF band.
 

arctic

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Feb 24, 2012
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OK, i have done a test of my own. I started by testing my new BC125AT.

I placed the scanner on the roof on my car in the dark so i could see the display blinking.
Her is the results :

The range to detect an UHF 5 watt hand held is around 30 yards :( The scanner is able to detect a 5 watt VHF handheld (2 meter band) at 100 yards I also tried a 27mhz handheld 4 watt, and the scanner detected the transmission on a range of only 20 yards.

I also tried a dual band magnetic antenna on my roof, it did not help at all on CB and UHF
but the range on VHF was increased to around 150 yards.

The bottom line is that the Close Call on the BC125AT isn't useful. I was hoping that the system could detect a traffic control or some other activity. But the range is so short that i don't understand that it can be useful.

I am going to make another test of my BCT15X in a few days. But i have used this receiver to listen
in to handheld VHF at much longer distances.
 

scanningisfun

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Jun 29, 2010
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I have tried to test the range of CloseCall on my new BC125AT by using a FMR UHF radio.I found out that the detection range is around 10 yards for 0.5 watt. I then got my 5 watt 70cm ham radio, and the range was now around 20 yards. My BCT15 x has a range on UHF on around 40 yards for a 5 watt handheld. I know that CloseCall works OK on my BCT15x, after all it detects aircraft in the AM 118-136mhz band a mile away. But after the UHF test i am wondering what the range is on the police VHF band.

This might be helpful:

Uniden Close Call - The RadioReference Wiki

Here is an excerpt:

"In general, a 1W portable will be captured up to around 100' (30m). 4W portable around 250' (75m), 25W mobile up to a half mile (805m) or more, and 100W base stations up to several miles/km. Other signals will affect Close Call range due to the nature of nearfield reception."

Jacob
 

UPMan

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Go out to the middle of the desert, and that .5W radio might be detected from over a mile or more. Detection will depend on the level of all other signals in the band. To be detected, the signal needs to be at least 18 dB higher than any other signal in that band.
 

parnass

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Jan 13, 2003
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Location
northern Illinois
Here are a few data points for the range of a BC346XT Close Call using the stock antenna:

Outdoors in a rural neighborhood:

162.4 MHz NOAA transmitter, 300 watts - 10 miles

133.5 AM aircraft - altitude unknown

Inside an enclosed shopping mall:

467.925 MHz FM sales staff HTs - at least 150 ft.
 
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