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Casey Lackey

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Jun 2, 2021, 12:13:23 PM6/2/21
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so do i need two dongles to listen to like local ems and fire?
or can i do it with just one?  and what type of antennas should i use? 
are the ones that come with my dongle fine? 

Sal Tepedino

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Jun 2, 2021, 12:21:17 PM6/2/21
to Casey Lackey, sdrtrunk
This all depends on the frequency bandwidth of your dongles, and the
range of frequencies that they use in their system. Most likely, yes,
unless you're using something with a wide bandwidth like an airspy.

As for the antennas, the ones that come with the dongles can work,
depending on lots of things. I'm still struggling with getting a good
signal, as I'm set up indoors and an antenna in the window just isn't
cutting it, so I'm not the best one to answer about antennas.
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Sal Tepedino

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Jun 2, 2021, 12:22:05 PM6/2/21
to Casey Lackey, sdrtrunk
That's yes, you'd probably need more than one dongle.

Casey Lackey

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Jun 2, 2021, 12:37:19 PM6/2/21
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well with just one dongle im not getting anything from my local fire or ems..  
im new to this stuff here lol ive been watching some youtube videos and im not having any luck at all 

Sal Tepedino

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Jun 2, 2021, 12:41:25 PM6/2/21
to Casey Lackey, sdrtrunk
Basically, a RTL-SDR v3 has a bandwidth of about 2.5 MHz, so if all of
your channels are within that range, then you're good. But there's a
good chance they're not. Having a second dongle will allow SDRTrunk to
use one for the command channel, and everything within range of that,
and use the second dongle to jump around to pick up other channels.

Or, you can get an Airspy, which has a 10Mhz range which will likely
cover your channel list.

Though it's hard to say without seeing which system you're talking about.
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Casey Lackey

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Jun 2, 2021, 12:46:22 PM6/2/21
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okay so what info can i share as i said im very new to this stuff 
 just to be on the safe side i did order another dongle they are cheap anyway .

Sal Tepedino

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Jun 2, 2021, 12:52:44 PM6/2/21
to Casey Lackey, sdrtrunk
If you can find your system on RadioReference
(https://www.radioreference.com/), it will list all of the frequencies
in use on your system, and you can work from there, or post it here if
you need help.
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Casey Lackey

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Jun 2, 2021, 1:01:06 PM6/2/21
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okay so here is my towns  frequency channels   
ive put the  station in but nothing   

Sal Tepedino

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Jun 2, 2021, 1:04:48 PM6/2/21
to Casey Lackey, sdrtrunk
Taylor county does not appear to be using a trunked system, so you'd
want to use a different program (such as GQRX for Linux) that will
tune to specific analog frequencies.

If you look below, Abilene is using a trunked system, which is what
you'd use SDRTrunk for.
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Casey Lackey

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Jun 2, 2021, 1:17:17 PM6/2/21
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i live in abilene which is the city of  taylor county..
we have  small commnity towns around us  

so on linux i could us GRQX ?  what about for windows?  

now for abilene ill need to use sdr trunk ive tried cple of them channels and got nothing 
that has my local police an stuff  i guess i dont know what i am doing lol 

Sal Tepedino

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Jun 2, 2021, 1:22:31 PM6/2/21
to Casey Lackey, sdrtrunk
If you look at that tables, if you want to listen to the frequencies
in the 'Taylor county' section, you'd use GQRX, or the like. I don't
use Windows, but I hear people like SDR#
(https://airspy.com/download/). If you want to listen to frequencies
in the Abilene P25 system (sub page here
https://www.radioreference.com/apps/db/?sid=11039) then you'd use
SDRTrunk.
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Casey Lackey

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Jun 2, 2021, 1:33:31 PM6/2/21
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i see the primary on Abilene ive used it and got nothing it just says idle..  
i see below there is other stuff with dec and hex codes ?  how do you tune into them  ?? 

im guessing since i cant hear nothing ill need another dongle? which i did order will be here saturday 
i may boot into ubuntu and mess with this stuff 
just curious which linux distro do you use? 

Jeff Chapman

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Jun 2, 2021, 2:02:16 PM6/2/21
to Casey Lackey, sdrtrunk
Casey,

I'm relatively new to this too, but here's some info on details that have helped me along the way.

SDRtrunk would be used on your Windows computer to listen to the Abilene P25 network.
This is an excellent starting point for SDR trunking radios: https://scannerschool.teachable.com/p/the-utlimate-beginners-guide-to-sdr

You are most likely going to need at least one additional SDR.  If the only entries you ever see in Status say "Encrypted" then you might
as well stop there.  You will not be able to decode encrypted signals.  In my area, all Police comm are encrypted but Fire and EMS are
still open and they all use the same P25 network.  P25 communications sort of depends on a strong saturation of signals throughout
the covered area.  Therefore, you should not need a lot of antenna to receive them.  If you start seeing a lot of "Tuner Unavailable" in
the Events Details column, that's a good sign you need another radio.

As for those VHF fire frequencies, you most likely would benefit from more antenna unless you are relatively close to the radio tower.
As stated, you likely would not use SDRtrunk to receive normal FM VHF/UHF signals.  I'm not familiar with GQRX but there are many
apps you can use on Windows, SDRsharp probably being the most popular at the moment.  I have not yet attempted to configure an SDR
as what we would think of as a 'normal'  scanner so I can't advise there.  But, in any case, you should see spikes for signals on the spectrum
display in the band with all those fire channels.

I hope this gets you headed in the right direction...

Regards, Jeff


Casey Lackey

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Jun 2, 2021, 3:02:15 PM6/2/21
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so ive used the signals everywhere video and i dont have a paid account for the radiorefence website. 
do i need that? ive input the frequency manual and i get nothing 

jim...@gmail.com

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Jun 2, 2021, 3:53:37 PM6/2/21
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Assuming the setup saettings are all good. Did you set your control chanel frequency to  855.2375
That is the control channel listed for  Abilene, TX  P25 phase II system.

jim...@gmail.com

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Jun 2, 2021, 4:09:09 PM6/2/21
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Also, It looks like four of Abilene's channels are encrypted. 

Jeff Chapman

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Jun 3, 2021, 8:50:41 AM6/3/21
to Casey Lackey, sdrtrunk
Casey,

The SignalsEverywhere video and the free version of ScannerSchool should get you the basics needed to get started.
I'd suggest maybe you share a screen capture of the "Now Playing" view, with the CONTROL channel selected
and the "Events" tab.  Include enough the spectrum view so we can see the signal strength.

This is a sample of my screen.  I've modified the colors of the spectrum view  Note the spikes, those are strong enough signals for me to receive okay.
That's where you need to start, you need a respectable signal strength.  That shouldn't be too hard to do.  I use the larger of the
two black antennas that came with the radio. It's sitting on top of a coffee can which is hanging from the wall.  I also use a homemade ground plane which I put on
a bracket and screw to the wall inside a closet.

image.png

dave38...@gmail.com

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Jun 3, 2021, 9:43:34 PM6/3/21
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On windows he can use sdr# with the scanner plug in and use one dongle on the Vhf freqs. Or with the same program, depending on exactly which vhf freqs, could possible get away with adding a few aux vfo's. 

Or he could buy Dsdplus fastlane and set up a scan list with fmp24 with one dongle to scan the Vhf freqs and run another instance with another dongle on the p25 phase 2 trunked system. One prog accomplishing 2 different things. 

Casey Lackey

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Jun 4, 2021, 12:02:25 PM6/4/21
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Jeffrey   
i dont have black antennas  do you have different antenna's? 

update on this stuff i still have not got my single dongle but i can now get some calls to come in on the p25 network..  
i think once i get another dongle i should be okay ..  
i also have another antenna coming as well once i get stuff working good  ill get some good antenna set ups 

Jeff Chapman

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Jun 4, 2021, 1:48:10 PM6/4/21
to Casey Lackey, sdrtrunk
Casey,

I presume you meant to say "second dongle".  Yes,  you will have better luck with P25 using a second dongle.
I thought you said you had kit antennas and I assumed they included the black ones.
I agree with dave38, if you are going to mix P25 and VHF narrow band, you may have better luck with DSDPlus Fastlane.

You ought to try receiving the VHF signals right away.  You should be able to do that just fine with a single dongle.
You can quickly test your setup by tuning to your local NOAA weather station, or even an FM broadcast.
There's a ton of stuff you can do with a single dongle.  The best place to start to play and build confidence in your setup is SDRsharp.
Start small and work up to P25.

Jeff


On Fri, Jun 4, 2021 at 12:02 PM Casey Lackey <clac...@gmail.com> wrote:
Jeffrey   
i dont have black antennas  do you have different antenna's? 

update on this stuff i still have not got my single dongle but i can now get some calls to come in on the p25 network..  
i think once i get another dongle i should be okay ..  
i also have another antenna coming as well once i get stuff working good  ill get some good antenna set ups 

On Thursday, June 3, 2021 at 8:43:34 PM UTC-5 dave38...@gmail.com wrote:

On windows he can use sdr# with the scanner plug in and use one dongle on the Vhf freqs. Or with the same program, depending on exactly which vhf freqs, could possible get away with adding a few aux vfo's. 

Or he could buy Dsdplus fastlane and set up a scan list with fmp24 with one dongle to scan the Vhf freqs and run another instance with another dongle on the p25 phase 2 trunked system. One prog accomplishing 2 different things. 


On Thursday, June 3, 2021 at 8:50:41 AM UTC-4 jeffrey....@gmail.com wrote:
Casey,

The SignalsEverywhere video and the free version of ScannerSchool should get you the basics needed to get started.
I'd suggest maybe you share a screen capture of the "Now Playing" view, with the CONTROL channel selected
and the "Events" tab.  Include enough the spectrum view so we can see the signal strength.

This is a sample of my screen.  I've modified the colors of the spectrum view  Note the spikes, those are strong enough signals for me to receive okay.
That's where you need to start, you need a respectable signal strength.  That shouldn't be too hard to do.  I use the larger of the
two black antennas that came with the radio. It's sitting on top of a coffee can which is hanging from the wall.  I also use a homemade ground plane which I put on
a bracket and screw to the wall inside a closet.


<snip> 

Casey Lackey

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Jun 4, 2021, 4:23:07 PM6/4/21
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and i did mean to say single dongle.. i can get some calls on p25.. ive got alot of help on the discord channel 
my first dongle came with two sets of silver antenna's not black ones!!
and i am running sdrtrunk on linux os  now  on one of my laptops.. 
and i am running a single dongle for now just one my second one will be here sunday..
now ive downloaded the csv file from radioref site and want to import it into sdrtrunk.. 
looks like ill need to convert i to xml ..  when i log on radio ref through sdrtrunk the. 
talk groups etc are not coming up for my county but there is a csv file full of frequencies

Jeff Chapman

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Jun 4, 2021, 4:31:38 PM6/4/21
to Casey Lackey, sdrtrunk

Casey,   Sounds great, you've come a long way from Newbie.  Good luck and have fun! Jeff

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Nick Turin

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Jun 27, 2021, 6:38:58 AM6/27/21
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Does anyone know where the author of the program disappeared?

пятница, 4 июня 2021 г. в 23:31:38 UTC+3, jeffrey....@gmail.com:

wllm...@gmail.com

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Jun 28, 2021, 8:51:48 AM6/28/21
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I can't imagine that Denny just up and decided to walk away from his creation!  I understand priorities of work and family matters and certainly hope that his absence has not been health and welfare related.

Neil Harvey

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Jun 28, 2021, 10:33:35 AM6/28/21
to wllm...@gmail.com, sdrtrunk

Did he get married, or have a child recently?  That would explain a lot.  Doing work for free is a luxury most can’t afford once that occurs.

 

Sent from Mail for Windows 10

Chance Lindsey

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Jun 28, 2021, 12:22:21 PM6/28/21
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Good news.  Denny is alive and well.

Getting concerned, I did a little bit of internet stalking and found what I believed to be a family member on Facebook that I sent a message to. She reported that other family commitments have had to take priority and Denny hopes to be back soon. I expressed how thankful we are all for his work and that we all understand, just checking on his welfare out of genuine concern.

Chance


Zach Whitaker

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Jun 28, 2021, 12:24:22 PM6/28/21
to Chance Lindsey, sdrtrunk
That is incredibly incredibly rude. 

Chance Lindsey

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Jun 28, 2021, 12:33:40 PM6/28/21
to Zach Whitaker, sdrtrunk
I am sorry if anyone felt that was rude. Unfortunately I have known of two people that were extremely active in an online community and suddenly fell ill and passed away. People who give so much, the least we can do is make a gesture back to the family. I am glad to know in this case Denny was fine. I don't care if he ever contributes another line of code to our hobby, knowing he is fine is the only matter of importance.  My only regret is waiting so long.

Neil Harvey

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Jun 28, 2021, 12:37:50 PM6/28/21
to Chance Lindsey, Zach Whitaker, sdrtrunk

I don’t think it was rude, not at all.  Zach has a strange sense of what is rude.

 

Sent from Mail for Windows 10

 

Michael Singewald

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Jun 28, 2021, 4:10:11 PM6/28/21
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If the call was to see when the author was going to update the software, that would be rude.  However, it sounds like this was a call showing concern for Denny, and I don't see how that could be considered rude.  It should actually be comforting to know someone went out of their way to check up on him.
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