SDRTrunk using RadioReference P25 Channel lists noob question

[weccwwe]

Hi all,

I have a brand new SDRtrunk setup and its working properly.

I do have a question concerning the P25 channels lists on the RR databases. I have the SDRtrunk setup up for Phase 1 and 2 and using the appropriate rtl dongle for this

The particular channel list I am looking at is this one:



1 - Do I need to input all the red and blue channels into SDRtrunk?
2 - Do they need to go to into a new separate channel each, or can I use the "tuner - multiple frequencies" option in SDRtrunk?
3 - What do I need to do with the single letter at the end of each channel?
4 - Where does the black digits information in the first three columns go into SDRTrunk?
5 - Why do I need a second RTL dongle? Or can I just use this one by itself?


My apologies about the noob questions.

 

[DSheirer]

1. You only have to put in the 'c = control' frequency. Use the P25 Phase 1 decoder. Since this is a simulcast site, use the 'LSM' (vs 'C4FM') option.

2. Use only 1 channel configuration. You can probably use just the single frequency input to start. If the primary control frequency repeater goes down for some reason, the site will automatically start using one of the 'a = alternate' control frequencies. If you notice this happens, then you can add the 'a = alternate control' frequencies using the multiple frequency input.

3. Ignore the single letter that follows the frequency. Those are just identifiers for the control and alternate control channels

4. You don't need to add this information to sdrtrunk. Use the P25 Phase 1 decoder and it will automatically decode all of these values from the control channel.

5. The minimum frequency for that site is 769.55625 and the maximum frequency is 774.91875, so the site has a frequency span of 5.6 MHz. If you're using an airspy dongle with 10MHz bandwidth, you'll only need 1 dongle. If you're using RTL-2832 dongles at 2.4 MHz sample rate/bandwidth, you'll need at least 2, probably 3 depending on how busy the site is, in order to ensure you catch every call that happens on every channel. You can use just 1 dongle to start, but you'll only be listening to a subset of the site's activity.

Denny

 

[weccwwe]

Great thank you sooooooooooo much for your help

This is exactly what I was looking for,

Wow great thanks again!

I did forget to mention this in my original post, it is a single rtl2832 dongle, and I am using my main Linuxmint laptop,

Regards

 

[weccwwe]

Ha just realized that I got my answers from the sdrtrunk creator himself, that is double awesome!

 

[weccwwe]

Actually one more question

When I get a second dongle, which frequency should I use from the list up top?

Just ordered a second one just now

 

[DSheirer]

The setup will remain the same. The second dongle will get tasked with calls/traffic channels as they get allocated by the control channel.

You'll need to make sure the serial number for the second dongle is different from the first dongle, otherwise sdrtrunk won't be able to distinguish between the gain and PPM settings for each dongle.

 

[weccwwe]

Great thank you again!

Learning way more asking you than the useless last 2 days of internet searches

 

[GTR8000]

Beware that AFRRCS is a Harris system, which means any frequency can potentially be used as the control channel. You may have to add all of those Edmonton simulcast frequencies to the file if they rotate like other Harris systems often do.

 

[weccwwe]

Good to know, Thank you GTR8000

Would you recommend me adding all the channels to the multichannel option all in the same file or create a single channel files for each in SDRTrunk?

Regards and thank you

 

[DRL-XM43]

Good to know, Thank you GTR8000

Would you recommend me adding all the channels to the multichannel option all in the same file or create a single channel files for each in SDRTrunk?

Regards and thank you

You would add them to multi channel option, if CC changes SDRTrunk will rotate through them until the active CC is selected by multi channel list. You can set the wait and see delay in seconds.

For support it is best to join the support forum

Redirecting to Google Groups

 

[weccwwe]

Great, Thank you, DRL-XM43

Cannot thank you enough all of you guys for leading me in the right direction.