Close Call vs. Input Frequencies

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Dave_D

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Hi all,

Which is better for detecting highway patrol vehicles (or other "nearby" mobile interests) -- Close Call or input frequencies?

I've had minor success with input frequencies on my BCT15, but then somebody tells me I'm going about it all wrong. To limit my reception range, I turn the squelch to max and employ the factory antennna, unextended (i.e., under the dash). Despite its concealment, the antenna receives plenty, but rarely a visual confirmation.

I'm told, "get a vehicle antenna and, for police/hp, use Close Call in VHF High and 800 MHz."

Is this right?! With a proper exterior antenna, won't I extend my range to receive even more false alarms?

Any advice is greatly appreciated.

Dave
 

DickH

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Dave_D said:
Hi all,
To limit my reception range, I turn the squelch to max and employ the factory antennna, unextended (i.e., under the dash). Despite its concealment, the antenna receives plenty, but rarely a visual confirmation.
Any advice is greatly appreciated.
Dave
Try removing the antenna. That will limit the range.
 

fineshot1

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Dave_D said:
Hi all,

Which is better for detecting highway patrol vehicles (or other "nearby" mobile interests) -- Close Call or input frequencies?

I've had minor success with input frequencies on my BCT15, but then somebody tells me I'm going about it all wrong. To limit my reception range, I turn the squelch to max and employ the factory antennna, unextended (i.e., under the dash). Despite its concealment, the antenna receives plenty, but rarely a visual confirmation.

I'm told, "get a vehicle antenna and, for police/hp, use Close Call in VHF High and 800 MHz."

Is this right?! With a proper exterior antenna, won't I extend my range to receive even more false alarms?

Any advice is greatly appreciated.

Dave

Dave - you sure seem to be going about it in the correct manor in my view and I have been scanning since the late 70's. You may even want to put a small BNC dummy load on the portable with the close call to limit your input freq receive to an even shorter range. I use an optoelectronics scout model 40 freq counter with a dual band rubber duck which works out well. For input freq detection the close call feature seems over sensative and the dummy load may help in that regard.....
 
D

DaveNF2G

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If you're having success with your methods, then they are not wrong. :)
 

Concrete1

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With Close-Call & an underdash antenna you are only going to reveive signals within 50-200ft or so, sounds like that's what you are looking for .... Even with an underdash antenna, the "regular receiver" will still pick some transmissions up that are miles away ...
 

ocscan

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If your looking for a "COP" detector while driving I would suggest more notice / detection range is better. Input frequencies will be detected further than Close Call. Other wise you might not detect the officer early enough and end up in a adverse situation....

That could end up costing you...like in insurance and stuff...
 

Dave_D

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Concrete1 said:
With Close-Call & an underdash antenna you are only going to reveive signals within 50-200ft or so, sounds like that's what you are looking for .... Even with an underdash antenna, the "regular receiver" will still pick some transmissions up that are miles away ...
This is exactly what I've been experiencing, except that at 200 feet, you'd expect more visual confirmations. Yes, the range of the "regular receiver" was several miles, adding to my confusion. To remedy this, I segregated the input and repeater frequencies into separate banks (er, "quick keys") so that I could run normally for recreational listening, or "optimized" for HP detection. Audible alerts tell me one from the other without glancing at the dash. Input freqs are prioritized. A downside to this is that there's virtually no CB reception.

I might not have been clear in my original message. The advice I received was to give up on input frequency scanning altogether, employ a legit antenna and rely solely on Close Call in the high VHF and 800 MHz bands. To be clear, I was not told to employ Close Call with a defeated antenna.

In fact, 200 feet is not enough warning and I'd really like to monitor CB. Heck, I've got an antenna and might as well put this to the test.... I'll letcha know what I find.

Thank you, everyone!

Dave
 

Gilligan

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I've actually set up a system on my 246T w/ just input freqs and high-priority outputs. I have been monitoring emergency vehicles transmitting up to about 1.5 miles away w/ it. Before EMSA pulls out around the corner, I know it. When the PD makes a traffic stop nearby, I know it. Inputs are the way to go. Close Call has proven extremely unreliable for me. If you are using your scanner solely as a detector (and not actually listening to the comms), just add Close Call in the background as you scan. I set my system up w/ each input followed by the output. The outputs are locked out. When I hear something, I just press hold and turn the knob one click to the output. Then I hear both sides of the conversation and I know they're close. It's been working out real good. One problem I've seen so far is scanning our highway patrols 800 Motorola system inputs. Too much data on the freqs makes it annoying so I don't bother with them. Just scan their conventional simplex channels instead. Hope this helps!
 

kb3hfp

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I'm not sure either would work reliably - Close Call usually picks up nearby police cars really well for me (heard a PSP unit right in front of me the other day, kinda cool to hear where they were going), but a lot of the time they won't be transmitting anyway, so either way it won't be a reliable way of telling who's nearby.

Input freq's could also be a problem since a *lot* of public safety agencies use pretty high power on the input...
 

hotdjdave

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Remember, while driving 60 MPH, you are traveling about 88 FPS (feet per second). Since the range of the Close Call feature is about 1000 feet, you would not have but more than a few seconds after hearing the transmission before you are actually at the transmission location.

If you program the mobile extender frequency instead, you will have up to a three mile range. This is how Bearcat BearTracker works.

What I have done on my BCD396T is program in the mobile extender frequencies, assign them as priority channels, and assigned them a tone alert - VOILA, I got BearTracker.
 

Gilligan

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kb3hfp said:
a lot of the time they won't be transmitting anyway, so either way it won't be a reliable way of telling who's nearby.
If a nearby unit replies to dispatch when assigned a new call, or when making a traffic stop, you'll hear it if they're close.
 

Dave_D

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Gilligan said:
Inputs are the way to go.... I set my system up w/ each input followed by the output. The outputs are locked out.
Sounds like my setup, almost exactly. Do you use an antenna?
 

Gilligan

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hotdjdave said:
Where I live (in The San Fernando Valley, Los Angeles, CA), CHP uses the portables (154.905 MHz) all the time to talk unit-to-unit.
So I guess they're pretty limited on range, then, right? And I'm sure they just love having to pull out their handhelds from their duty belt while driving around...been there before and it's a pain.
 

Gilligan

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Dave_D said:
Sounds like my setup, almost exactly. Do you use an antenna?
Yes, I actually have an Optoelectronics DB32 I saved from my Scout. If I set the radio on the desk then I'll put on the 6-inch stock antenna. But the 1-inch DB32 does the job just perfect.
 

hotdjdave

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Gilligan said:
hotdjdave said:
Where I live (in The San Fernando Valley, Los Angeles, CA), CHP uses the portables (154.905 MHz) all the time to talk unit-to-unit.
So I guess they're pretty limited on range, then, right? And I'm sure they just love having to pull out their handhelds from their duty belt while driving around...been there before and it's a pain.
For the most part, I hear CHP units using them for traffic breaks, coordinating with the other CHP units involved; when there is an accident and on party is at one spot on the FWY and the other party is down the road aways, and the CHP units talk to each other; or one is on the side of the road watching traffic and communicating with another unit down the road of what he/she has seen; and stuff like that. I think they do it to stay off the normal CHP channels.

So, yes, they are limited on range...probably less than an mile. However, in Los Angeles freeway traffic, a mile is a long way.

And before someone asks/comments: yes, the CHP officers are usually in their cars when I see/hear them doing this; I do believe they are using their mobile and not the car radio - although I could be wrong. I guess my point is why would I hear them (both) on the mobile extender frequency (154.905) when both of them are in their cars? Wouldn't they just use the car radio, instead? Hence, my premise that they want to communicate locally with each other without using the car radio/CHP system.
 
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kb3hfp

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Gilligan said:
If a nearby unit replies to dispatch when assigned a new call, or when making a traffic stop, you'll hear it if they're close.
Yep, that's what I hear the most on Close Call... just saying that it's not a reliable way to detect nearby LEOs.
 

Dave_D

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Dave_D said:
I've got an antenna and might as well put this to the test.... I'll letcha know what I find.
Okay, I've operated the antenna in Nevada for a couple weeks and then took a road trip across northern California (sans antenna -- different car). As promised, here's what I found -- and much of it corroborates what has already been said:

CLOSE CALL PERFORMANCE (CITY): ~50 FEET
Even with the antenna, Close Call appears to have a range of about 50 feet in Reno. For example, when driving through the airport, I'll pickup taxicab dispatch when I drive by their coral. But then, parked in line-of-site, only 500 feet away, nothing. Similar performance was verified by airport security, both vehicular and handheld. Surprisingly, the airport security handhelds were setting off Close Call when within 20 feet or so, whether the officer was talking or not. Do those handhelds repeat?

CLOSE CALL (RURAL): ~200 FEET (?)
I live up in the Sierra Mountains. After two weeks of Close Call Only mode, I bagged only four Close Call hits. Three of these had no visual confirmation. The fourth was a Sheriff performing a traffic stop 100 feet away. Of the unconfirmed hits, one almost certainly came from the police station, 200 feet away.

INPUT FREQUENCIES (CALIFORNIA, NO ANTENNA): 500 FEET
Switching back to input frequencies, my BCT15 showed a marked improvement in California, no doubt from the mobile extenders employed by CHP. Of a dozen or so hits, 75% were visually verified; typically within 300 feet or so. Not included in this count were a dozen or more "Lime 5" hits, of which none were visually verified. Now, if only Nevada Highway Patrol would employ mobile extenders....

CONCLUSION
In California, input frequencies rock! With a proper antenna, I would expect CHP detection to rival that of a radar detector, both in range and accuracy. In Nevada, however, where mobile extenders are not employed by NHP, input frequencies are much less reliable. Nonetheless, it is better to receive something from three miles away than nothing at 100 feet. Again, input frequencies win.

In its defense, Close Call is an excellent option for the house. At 200 feet, it just extends to my immediate neighborhood.
 

wolter

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hotdjdave said:
And before someone asks/comments: yes, the CHP officers are usually in their cars when I see/hear them doing this; I do believe they are using their mobile and not the car radio - although I could be wrong. I guess my point is why would I hear them (both) on the mobile extender frequency (154.905) when both of them are in their cars?
Maybe you're hearing someone else's active extender?

All traffic of that particular channel is simulcasted over the extender. Sit on the extender freq for any length of time and you'll eventually hear other units as well, ones that clearly are not using the extender. Or their extenders may be active for whatever reason. But, this doesn't mean they are using their handhelds. All radio traffic of that particular channel will be broadcasted on the extender freq, even if the officer is not using his handheld.

CHP offices will oftentimes broadcast all channel traffic over the extender freq for officers that are out on foot while at the office, either in the parking lot or wherever. All of my local offices do this. It may be what you are picking up.

hotdjdave said:
Wouldn't they just use the car radio, instead?
The probably are, using channel 2 that is used for car-to-car. This will also go out over an active extender.
 
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