Digital Scanning Question

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TheCoolMatrix
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Digital Scanning Question

Post by TheCoolMatrix »

Hi all!

With all the agencies that have gone to P25 on the south shore, and many that are going to be moving to P25 or are in the process of going to P25, I am looking at ways to listen without missing transmissions. I primarily will be listening to Hingham, Weymouth, Braintree (still analog), Scituate, Cohasset, Quincy (in process of moving to P25), Milton (analog), and a handful of others. I have a BCD325P2 and while it does the job, I have noticed some missing transmissions (could be the location of the unit when trying to listen). Would a XTL 2500 or 5000 work for something like this (RX only of course)? Or am I better off getting a 996P2?

Any help is appreciated!

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ecps92
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Re: Digital Scanning Question

Post by ecps92 »

Scanners, in both Analog Mode and P25 Mode would likely need to ensure "DELAY" is on, for each of those channels, otherwise when the transmission ends, it begins scanning again
vs a hang/dwell/delay to hear the next transmission.

what makes you think or know you are missing transmissions ?
TheCoolMatrix wrote:
21 Nov 2021 22:00
Hi all!

With all the agencies that have gone to P25 on the south shore, and many that are going to be moving to P25 or are in the process of going to P25, I am looking at ways to listen without missing transmissions. I primarily will be listening to Hingham, Weymouth, Braintree (still analog), Scituate, Cohasset, Quincy (in process of moving to P25), Milton (analog), and a handful of others. I have a BCD325P2 and while it does the job, I have noticed some missing transmissions (could be the location of the unit when trying to listen). Would a XTL 2500 or 5000 work for something like this (RX only of course)? Or am I better off getting a 996P2?

Any help is appreciated!
Bill Dunn N1KUG
Cruise Ship Frequencies
http://scanmaritime.com

"The tougher it is to find a frequency, the more it makes me want to work to find it. - I've learned to use the SEARCH Button"

ScanBoston
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Re: Digital Scanning Question

Post by ScanBoston »

If you'd like to pay less money in my opinion Whistler scanners do a better job with P25 than Uniden. https://www.bestbuy.com/site/whistler-d ... =212&loc=1 No P25 Phase 2 with this but I don't think you need it for what you have mentioned.

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W1KNE
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Re: Digital Scanning Question

Post by W1KNE »

TheCoolMatrix wrote:
21 Nov 2021 22:00
With all the agencies that have gone to P25 on the south shore, and many that are going to be moving to P25 or are in the process of going to P25, I am looking at ways to listen without missing transmissions. I primarily will be listening to Hingham, Weymouth, Braintree (still analog), Scituate, Cohasset, Quincy (in process of moving to P25), Milton (analog), and a handful of others. I have a BCD325P2 and while it does the job, I have noticed some missing transmissions (could be the location of the unit when trying to listen). Would a XTL 2500 or 5000 work for something like this (RX only of course)? Or am I better off getting a 996P2?
An XTL2500 or 5000 is overkill for what you're accomplishing. The 996P2 is the same scanner as the 325P2, so if you miss transmissions on a 325, you're going to on a 996. You could be suffering from a number of items.
We don't know your location, so some of this is assumption. But you may be near another strong UHF transmitter? When it comes up, it overloads your front end and you don't receive what you want.
Some users have had good luck turning off the NAC decode and switching to "search", so the scanner picks up P25 transmissions regardless of the NAC.

And still, sometimes officers don't reply by the radio but rather through messaging programs on their in cruiser laptops.
Mike Fitzpatrick
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jbella
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Re: Digital Scanning Question

Post by jbella »

If it's for your car, an XTL may be a better option as far as Rx, but it's a long step and if you're not programming it yourself, much more cumbersome.

TheCoolMatrix
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Re: Digital Scanning Question

Post by TheCoolMatrix »

I appreciate all of your responses. I am going to be installing into my vehicle. I have heard that the XTLs work well with P25 in the conventional manner and if the brick is put in the trunk, there isn't much in the way. I will be sure to send pictures of my finished product once it's complete.
ecps92 wrote:
22 Nov 2021 06:33
Scanners, in both Analog Mode and P25 Mode would likely need to ensure "DELAY" is on, for each of those channels, otherwise when the transmission ends, it begins scanning again
vs a hang/dwell/delay to hear the next transmission.

what makes you think or know you are missing transmissions ?
I thought that something was missed one day when one agency was talking about something over the air, and I went to Broadcastify where it came out perfectly fine. It could have very well been my position at that point in time (driveway under trees between two houses).

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ecps92
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Re: Digital Scanning Question

Post by ecps92 »

or your radio [just like an XTL will] had already gone back to Scan and was already locked onto another frequency when the reply occured. [Nothing can fix that issue]
TheCoolMatrix wrote:
22 Nov 2021 13:24
I thought that something was missed one day when one agency was talking about something over the air, and I went to Broadcastify where it came out perfectly fine. It could have very well been my position at that point in time (driveway under trees between two houses).
Bill Dunn N1KUG
Cruise Ship Frequencies
http://scanmaritime.com

"The tougher it is to find a frequency, the more it makes me want to work to find it. - I've learned to use the SEARCH Button"

JBP
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Re: Digital Scanning Question

Post by JBP »

Major drawback for an XTL5000 or any ASTRO25 series radio is the scan list is limited to 16 channels. So you could only scan 16 channels at any given time compared to the thousands you could with a scanner.
Jeremy
KB1REQ (DMR-MARC: 3125125)

JohnRugg
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Re: Digital Scanning Question

Post by JohnRugg »

It’s also possible that at least some of these systems are using linear simulcast technology, which is phase modulated and not frequency modulated. I do see multiple transmitters licensed for almost all of these communities. Traditional scanners cannot decode this properly and will suffer from the problems you are having. The solution is to get a receiver that properly decodes QPSK, such as Uniden SDS, Whistler TRX, Unication pagers or P25 LMR receivers (such as XTL). Read more here:

https://wiki.radioreference.com/index.p ... Distortion

John

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ecps92
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Re: Digital Scanning Question

Post by ecps92 »

Good explaination John

So far the only Phase modulated one, still in testing is Quincy - all others come in fine [YMMV]
JohnRugg wrote:
23 Nov 2021 05:01
It’s also possible that at least some of these systems are using linear simulcast technology, which is phase modulated and not frequency modulated. I do see multiple transmitters licensed for almost all of these communities. Traditional scanners cannot decode this properly and will suffer from the problems you are having. The solution is to get a receiver that properly decodes QPSK, such as Uniden SDS, Whistler TRX, Unication pagers or P25 LMR receivers (such as XTL). Read more here:

https://wiki.radioreference.com/index.p ... Distortion

John
Bill Dunn N1KUG
Cruise Ship Frequencies
http://scanmaritime.com

"The tougher it is to find a frequency, the more it makes me want to work to find it. - I've learned to use the SEARCH Button"

TheCoolMatrix
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Re: Digital Scanning Question

Post by TheCoolMatrix »

JohnRugg wrote:
23 Nov 2021 05:01
It’s also possible that at least some of these systems are using linear simulcast technology, which is phase modulated and not frequency modulated. I do see multiple transmitters licensed for almost all of these communities. Traditional scanners cannot decode this properly and will suffer from the problems you are having. The solution is to get a receiver that properly decodes QPSK, such as Uniden SDS, Whistler TRX, Unication pagers or P25 LMR receivers (such as XTL). Read more here:

https://wiki.radioreference.com/index.p ... Distortion

John
This is exactly the problem that I am having. I appreciate your insight in this. I have been reading into the XTS/XTL series radios, and I have one question. It may be stupid, but I want to cover my bases. I have heard that non-affiliate scanning needs to be enabled on the radio in order to keep it from trying to affiliate with the system. Is that only for trunking systems? Or are conventional P25, and some analog part of that as well?

JohnRugg
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Re: Digital Scanning Question

Post by JohnRugg »

TheCoolMatrix wrote:
24 Nov 2021 19:54
This is exactly the problem that I am having. I appreciate your insight in this. I have been reading into the XTS/XTL series radios, and I have one question. It may be stupid, but I want to cover my bases. I have heard that non-affiliate scanning needs to be enabled on the radio in order to keep it from trying to affiliate with the system. Is that only for trunking systems? Or are conventional P25, and some analog part of that as well?
That is for Trunking. For conventional (analog or P25), just check off Receive Only in the conventional personality.

John

TheCoolMatrix
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Re: Digital Scanning Question

Post by TheCoolMatrix »

JohnRugg wrote:
25 Nov 2021 19:25
That is for Trunking. For conventional (analog or P25), just check off Receive Only in the conventional personality.

John
Excellent. Thanks so much for your help John! I will send pictures of the finished product fully installed in the next few weeks!

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