SDRTrunk and CC/VC

[AngWay]

The frequencies shown in the database for the 3 Buchanan County sites are:

2 (2)	013 (D)	Honaker	Buchanan	152.6825c	152.7125c	161.875	162.000
2 (2)	017 (11)	Oakwood	Buchanan	152.8175c	161.800c
2 (2)	027 (1B)	Elkin's Branch	Buchanan	161.900c	161.9375c	161.950c

If you look at the diagrams (and other information given) in post #24, what conclusion do you reach?

i am like brand new to all of this and my math is not so great i'm sorry but i think what u are saying is i don't need the third dongle . but i never was able to connect to this new site until i put the j pole antenna up so i'm just wondering if their would be any benefit to connecting to it or will i still get the same stuff just by using the sites i was using before. and whats up with the 152 site now i can barely get a good signal on it when before it was my strongest site

 

[dave3825]

yes it is the third site i changed the freqs to 161.95000 and it locked on.

Since your a premium member here, you should be importing the sites of interest, and all talkgroups. This way you get the proper freqs associated with the system.

i can't wait until i get the j pole on the roof i'm hoping i'll get even better signal i don't believe i'll need a LNA what do u think?.

Depends on how the splitter handles the signal.

and big question here since i can lock onto 3 sites now will i need the third dongle or no?

No, third dongle not needed. Set it up in DSDPlus.

my math is not so great

Neither is mine. I talk to Google and Siri more than anyone.

Take all 152 freqs and subtract lowest freq from highest freq. Do the same for all 16X freqs. As long as your under 2.4 your good,which you are.

and how come in the picture is the freqs for state police different than the CC if u know why i'm curious.

It's a statewide system and they have many licenses. And as I suspected with the other site, there could be more freqs being used that are not listed as such in the database. Like 152.7250 (licensed to Oakwood site and not listed in the database) as seen in your screenshot. 152.8100 may pop up at some point. Remember, it's a statewide system but your county is only 19,000. Not very busy compared to my county of 1.5 million.

 

[AngWay]

Since your a premium member here, you should be importing the sites of interest, and all talkgroups. This way you get the proper freqs associated with the system.



Depends on how the splitter handles the signal.



No, third dongle not needed. Set it up in DSDPlus.


Take all 152 freqs and subtract lowest freq from highest freq. Do the same for all 16X freqs. As long as your under 2.4 your good,which you are.

View attachment 164506



It's a statewide system and they have many licenses. And as I suspected with the other site, there could be more freqs being used that are not listed as such in the database. Like 152.7250 (licensed to Oakwood site and not listed in the database) as seen in your screenshot. 152.8100 may pop up at some point. Remember, it's a statewide system but your county is only 19,000. Not very busy compared to my county of 1.5 million.

why do u say set it up in dsdplus? is it better than sdrtrunk for some specific reason? and ur saying i don't need to lock onto all three sites? because the two dongles will cover everything? so why is their that 3rd site if i don't need it?

 

[dave3825]

I meant all the county conventional freqs, put them in a scanlist and let that run too. Except for Grundy FD, says they are encrypted.

 

[RMason]

i think what u are saying is i don't need the third dongle .

Correct. The frequencies of this additional site are within the range of the existing two dongles.

would be any benefit to connecting to it or will i still get the same stuff just by using the sites i was using before.

This is something that you will have to determine. Since the three sites are in close proximity to each other, it is likely a talkgroup will be affiliated with all sites. But there is no guarantee that all talk groups will be carried on all sites. One just has to review logs and listen for a while and take note of what talkgroups are carried where to make that determination

so why is their that 3rd site if i don't need it?

Multiple sites on extend the coverage of the system. As an example - Just as you are having trouble getting a good signal on all three sites in the county, users of the the system in the northeast portion of the county may not get a good signal on a site in the southwest portion.

 

[AngWay]

Correct. The frequencies of this additional site are within the range of the existing two dongles.


This is something that you will have to determine. Since the three sites are in close proximity to each other, it is likely a talkgroup will be affiliated with all sites. But there is no guarantee that all talk groups will be carried on all sites. One just has to review logs and listen for a while and take note of what talkgroups are carried where to make that determination


Multiple sites on extend the coverage of the system. As an example - Just as you are having trouble getting a good signal on all three sites in the county, users of the the system in the northeast portion of the county may not get a good signal on a site in the southwest portion.

ok good thats what i will do. any idea on why my 152 site is so weak now that i'm using a outside antenna it was my strongest on the little antenna that came with the dongles.

 

[RMason]

No, third dongle not needed. Set it up in DSDPlus.

As an aside - I use SDRTrunk to monitor and record traffic. In parallel, I use DSD+ to explore. You can use DSD+ to gather information for a site. What frequencies are used on a site? What talkgroups are carried on a site? What is the callsign? All of this can be identified and logged using DSD+. You can start by tuning your third dongle to one of the control channel frequencies - and see where it takes you.

I realize that this opens up a whole new conversation, but it might also help to answer some of your curiosities.

 

[AngWay]

As an aside - I use SDRTrunk to monitor and record traffic. In parallel, I use DSD+ to explore. You can use DSD+ to gather information for a site. What frequencies are used on a site? What talkgroups are carried on a site? What is the callsign? All of this can be identified and logged using DSD+. You can start by tuning your third dongle to one of the control channel frequencies - and see where it takes you.

I realize that this opens up a whole new conversation, but it might also help to answer some of your curiosities.

ok sounds good . i will use DSDPlus Fastlane and see what happens Thank u very much

 

[dave3825]

To use DSDPlus on three sites you would need to run three single dongle instances of DSDPlus. But you would hear echoing if same tg is active on another site.

You could run one site and let it run a few days. That could indicate any more freqs in use not listed in the database.

 

[RMason]

To use DSDPlus on three sites you would need to run three single dongle instances of DSDPlus. But you would hear echoing if same tg is active on another site.

You could run one site and let it run a few days. That could indicate any more freqs in use not listed in the database.

Yes - use one dongle to monitor a single site at a time.....

 

[AngWay]

Yes - use one dongle to monitor a single site at a time.....

ok any idea what this is my control channel is in the middel and i always see slivers of a freqs in my feed but i never hear anything am i missing something. i circled them in red.

 

[AngWay]

To use DSDPlus on three sites you would need to run three single dongle instances of DSDPlus. But you would hear echoing if same tg is active on another site.

You could run one site and let it run a few days. That could indicate any more freqs in use not listed in the database.

alright i will try that

 

[dave3825]

Those other trails could be other agencies and might not be part of the system. Your looking at a spectrum that will show any and everything it sees, not just the stars system,

Also, lower your gain. Noise floor is very high. The J Pole is picking up much more than the sdr antenna.

 

[AngWay]

Those other trails could be other agencies and might not be part of the system. Your looking at a spectrum that will show any and everything it sees, not just the stars system,

Also, lower your gain. Noise floor is very high. The J Pole is picking up much more than the sdr antenna.

ok i'll lower it. huh i still ain't getting good signal strength on the 152 CC i did with those cheap antennas my 161 CC is alot stronger than it was before. i opened sdr++ and was going through looking for frequencies and i find alot of them but i can't hear anything on any of them i'll post a pic of one of the freqs maybe u know what kind it is.

 

[dave3825]

Turn off Tuner AGC and RTL AGC
Turn up the Gain
Select NFM, WFM is for radio broadcast stations.
Adjust PPM if red line is not dead center of signal.

 

[AngWay]

Turn off Tuner AGC and RTL AGC
Turn up the Gain
Select NFM, WFM is for radio broadcast stations.
Adjust PPM if red line is not dead center of signal.


View attachment 164517

alright i did that i was looking at signals online Project 25 (P25) - Signal Identification Wiki and i think it's a conventional signal i have several of them i can tune to but all i get is static from them.

 

[dave3825]

Set the gain to zero. Change freq to one of the cc . Slowly raise the gain, until the signal reaches its highest point, and when the noise floor just starts to rise. Then back it off a hair.

 

[RMason]

i opened sdr++ and was going through looking for frequencies and i find alot of them but i can't hear anything on any of them

Do you get audio on any of the NOAA weather stations in SDR++? (Just wanting to work with a known quantity for debug purposes)
You should be able to receive one of these in Buchanan County
Gilbert 162.475
Pikeville 162.400

NOAA Broadcasts are found in the VHF public service band at these seven frequencies (MHz):
162.400
162.425
162.450
162.475
162.500
162.525
162.550

 

[AngWay]

Set the gain to zero. Change freq to one of the cc . Slowly raise the gain, until the signal reaches its highest point, and when the noise floor just starts to rise. Then back it off a hair.


View attachment 164519

i gave that a shot and i'm still just getting static. i did like u said with the CC . i know there is a signal here i can see it don't understand why i can't hear nothing tho.

 

[AngWay]

Do you get audio on any of the NOAA weather stations in SDR++? (Just wanting to work with a known quantity for debug purposes)
You should be able to receive one of these in Buchanan County
Gilbert 162.475
Pikeville 162.400

NOAA Broadcasts are found in the VHF public service band at these seven frequencies (MHz):
162.400
162.425
162.450
162.475
162.500
162.525
162.550

yeah i get audio from the NOAA 162.500 is where i get it