For those whose agencies have encrypted what, if anything, are you doing to find out if police might be lurking around your area? I have close call enabled and haven't really paid much attention to it, and I'm wondering whether it's a valid and reliable means for alerting you of any nearby police activity? I live in a quiet neighborhood and am not super close to any towers but will occasionally pick up CC hits from aircraft flying over. But that's about it.
Close Call
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jonwienke
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Close Call is only going to pick up handhelds within a few hundred feet. Possibly less, depending on the RF noise floor in the area. You'd be better off having a RTL dongle + SDR# doing band scans looking for activity on unknown frequencies. If you set up the scan plugin right, you can scan bandwidth at 8-10MHz/s.
You could scan repeater inputs for conventional repeaters...
For a trunked system, scanning the system input frequencies is an option.
And depending on the scanner, trunked system talkgroups can be set for a specific LED color, blink pattern, and/or audible alarm.
You might try these options in addition to attenuation in order to receive only "strong signals"
Of course the best way is to look for red and blue lights....
For a trunked system, scanning the system input frequencies is an option.
And depending on the scanner, trunked system talkgroups can be set for a specific LED color, blink pattern, and/or audible alarm.
You might try these options in addition to attenuation in order to receive only "strong signals"
Of course the best way is to look for red and blue lights....
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Spitfire8520
Might be slightly less clueless! =)
The drawback of Close Call or looking at the input frequencies on a trunked radio system is that it will let you know when anyone on the system near you. Depending on your local situation, you may end up getting someone other than an officer in most cases like public works or a bus passing by.
This method of monitoring also uses the assumption that the nearby officer is talking up a storm, which is unlikely unless something major is happening. If they are using that much airtime, then you will probably hear the sirens before you find out by monitoring the input. It would probably be more effective to use a radar detector.
This method of monitoring also uses the assumption that the nearby officer is talking up a storm, which is unlikely unless something major is happening. If they are using that much airtime, then you will probably hear the sirens before you find out by monitoring the input. It would probably be more effective to use a radar detector.
Also if the trunked system is Phase-2 TDMA close-call will not trigger or detect the emission. It needs a continuous wave carrier.
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Couldn't a talk group be used in a programed band plan in a scanner for all the repeater inputs and thus when that TG and frequency fires up you'll know who it is instead of getting the spurious bus or public works truck, etc?
I could have swore I did this once with a dedicated bank in my BC296D with just talk groups and repeater inputs. But it's been years and I can't remember.
It should work because if you monitor a voice channel in DSD+ you get the TG and RID. But those are in fact repeater outputs. Then again, repeater inputs would have the TG data anyway, right?
I could have swore I did this once with a dedicated bank in my BC296D with just talk groups and repeater inputs. But it's been years and I can't remember.
It should work because if you monitor a voice channel in DSD+ you get the TG and RID. But those are in fact repeater outputs. Then again, repeater inputs would have the TG data anyway, right?
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And this may solve the FBI/Russia metadata radio hack just recently. Though, I'm sure some good TSCM equipment could be deployed for TDMA.
I have never had close call pick up any aircraft going over my apartment building I have a discone antenna on my fourth floor balcony and the planes coming into Buffalo NY never set off the close call. on my 396t scanner or my new SDS100 Scanner. what setup are you using on close call ???
Steve
I have tried it with all bands on and also just the air band with no luck,
Steve
Steve
doctordialtone
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When I first got into scanning and radio in general I had my own version of "close call." It was that Radio Shack 25 MHz-2400 MHz frequency counter. I connected it to my Radio Shack discone and I was then able to get the frequency the train was using just down the road every time they passed on by. At the time I had no idea what frequency they were using. But the frequency counter confirmed it.
Ubbe
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Close Call needs to see a huge difference in strenght from the signal from all other signals in the air. If I can see and hear the airplane I get a hit but if I use a FM broadcast trap filter I can't even hear the aircrafts that Close Call picks up. The difference are dramatic. The more narrower filter you can use to filter out all other transmissions the better Close Call will work.
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Wouldn't be great if SDR software supported close call? Maybe SDR# has a plugin-in I'm not aware of?
Ubbe
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Isn't there a mode that makes you listen to the strongest signal in the spectrum? I'm almost sure there was one in the scanner plugin.
The close call in scanners, at least up to recently, use a dedicated and industri standard frequency counter chip.
/Ubbe
The close call in scanners, at least up to recently, use a dedicated and industri standard frequency counter chip.
/Ubbe
TailGator911
Silent Key/KF4ANC
I live about a mile from the main gate at Wright-Patterson AFB right in line with main runways and those big C-130s come pretty darn close sometimes and I have CC enabled (airband) on my BC125AT but no hits from overhead aircraft - ever.
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