P25 System has many events but no voice or calls listed?
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Prerunning
Dec 31, 2019, 4:20:46 AM12/31/19
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Not sure whats going on. Ive been monitoring for over 12 hours but yet to see any voice or calls listed in the events.
the system is small but supposed to be unencrypted P1. One event says use encryption null. Does that mean the system is encrypted? https://www.radioreference.com/apps/db/?sid=8660
Thanks
DRL-XM43
Dec 31, 2019, 12:46:11 PM12/31/19
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The system is simulcast try changing the decoder from normal.
Dean Sauer
Jan 2, 2020, 11:50:09 AM1/2/20
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On Tuesday, December 31, 2019 at 4:20:46 AM UTC-5, Prerunning wrote:
Not sure whats going on. Ive been monitoring for over 12 hours but yet to see any voice or calls listed in the events.the system is small but supposed to be unencrypted P1. One event says use encryption null. Does that mean the system is encrypted?
Theres a couple things in this....
First and foremost.. for me... I think you need to fine to the setup for the tuner(s)...
I'd like to see that these things are actually working myself for VHF I use NWR sites as a test most of this 300W-1K stations and high towers getting these and multiple ones is a good sign you have a good VHF setup.
I do this via:
rtl_fm -d 1 -F 0 -E dc -M fm -p 50 -g 19.1 -f 162.55M -s 48000 - | aplay -Ddefault:CARD=Set -r 48k -f S16_LE -t raw
Actually SDRTrunk can do this...
Setup a channel for your local NWR's.. NBFM WIDE MODE IMPORTANT WIDE MODE!!!
Then start them up one at a time to see that you get signals.... There is NO SQUELCH mode for the NBFM mode in SDRTrunk right now.. hopefully maybe soon please Santa (Hint! :) :) ;) ) so maybe just go through the 162.400-550 band one at a time testing what you get.. Get signals??? Good signals based on the stations and your location???
Which dumps out NWR to my speakers... you are using a non Linux, so I have no clue on it... but testing out the dongle(s) for operation would be a starting point for me.
Next.. SIGNAL LEVEL..
Do NOT use "AUTOMATIC" for the Master Gain.
I know you stated you tried this, but look at those screen shots compared to the one I am attaching.. see all that noise and the signal buried down in the noise.. versus mine where the signal(s) are NICE SPIKES..
I would PREFER TO SEE that... NOT THAT THIS IS the be all end all.. but as start I'd like to see NICE CLEAN SPIKES for signals not bumps barely out of the noise floor...
Set Master gain to 49.6 and then post what you get for the signals....
Next, if you posted it, I missed it some how.. Antennas? Spefically what are you attaching to this a this time?? If its anything that comes with the dongles, its likely GARBAGE! When you consider the original use of these TV (even if its DVB-T) these are signals that ORDERS OF MAGNITUDE STRONGER ie: 30-40-50KILO watts versus. 200-500WATTS thats a big difference! Your licensee is 300W.. That a 100X factor..
I know you posted your drove there and nothing changed... more on this in a moment..
Using PROPER antennas for things is a must to end all of grief and hair pulling...
What is the antenna on the roof??? Length of coax, type of coax ie: RG6... I know you stated you needed an adapter, Ebay or even amazon... while its not the most perfect way.. there are some setups which are "CABLE SPLITTERS" which take an input and divide to 2 outputs be it SMA or the MCX, since this has 2 SDR's I'd suggest to get one and with the appropriate connector for the SDR and your input...If you have to get an adapter from your coax to SMA. Less adapters the better... and I will repeat these are not best way to do this.. but for some testing they will do.
Once you got good signals.. nice spikes....
Then lets look at what SDRTrunk is doing...
ENABLE LOGGING..
Under the channel turn ON DECODED MESSAGE LOGGING...CHECK ALL FOUR BOXES! This going to LOG A LOT A LOT OF DATA! Run it for a while and then I will say what to post...
Now the part of this that makes things funky....and possibly an issue...
VHF trunking like your has NO CHANNEL NUMBERING PLAN... When 850Mhz trunking first came about the CC for Motorola said goto channel 1 the radio knew to look up channel 1 and its formula would spit out say 851.1250 (this is just an exmaple these are NOT CORRECT VALUES!) radio would tune to 851.1250 and you would hear the group... This is why REBANDING screwed over all those radios.. the CC told it to go to 1 and it went to 1, but 1 was no longer 851.1250 it was 851.2250 (again example) ... Now EDACS trunking never used this "standardized" channels they used Logical Channel Numbers or LCN's thats why you had to program then in a SPECIFIC ORDER be it scanner or real radio.. The CC told it to go to 15 and the radio/scanner tuned to memory 15.. Program it wrong, and no work!
So with that...
P25 has whats called EXPLICIT and IMPLICIT messages...
The root of your issues could be that the radios are programmed only for IMPLICIT message.. that is the radios are setup much like an EDACS LCN and they tune to channel 1...say 155.235, the CC says goto 3 and they go to 155.340 (EXAMPLES) as thats whats in memory 3.. The CC is not sending out any RFSS info about bands because the radios don't need it... they have it all programmed and know what to do...
The logging of the data will tell this...
I will let the author speak as to whether SDRTrunk can deal with only implicit V/UHF trunking setups..
BUT
The RFSS blocks really should still have data for a base frequency.. etc.. which is why I think you need to get the signals up out of the noise... then we see if you get RFSS Band etc... We want to see IDEN_UP_VU messages and data.
The one VHF p25 system I have sends data for EXPLICT grants.. BUT THE P25 standard allows for:
" This information coincides with the
information sent in the IDEN_UP message or from the internally
pre-programmed SU information"THAT OR is a critical.
What happens when you PROGRAM ALL THE FB8 channels for this system into SDRTrunk and start them?
Do you get voice decodes????
My hunch is that SDRTrunk can't deal with IMPLICIT only V/.UHF trunking???
Back to you....
Prerunning
Jan 3, 2020, 12:39:45 AM1/3/20
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I appreciate all the info. I have the logs from when i was parked near the tower and the screen shots of how clear the signal was. I had all of the options in logging selected when i was testing it. I uploaded the entire sdrtrunk log folder to my google drive.
https://drive.google.com/open?id=1Xh3p467oEKIaYyils-I52qaeXstf8Yuh
This is a link to the 2 sdr unit and antennas it came with.
The antennas are not great but its a strong line of sight signal to the house from the pole and if i remember correctly the license said 100 watts. But i ordered some adapters and cables to connect a couple of other antennas i have.
Im not sure of the brand scanner antenna i have now but it works really well. I ordered it from Germany about 5 years ago. It was about 100 bucks
When im in the house and have the antennas standing up I can pick up the weather stations just fine and the tone on the control channel sounds nearly the same. My scanner is a bit cleaner it but the sdrs are still perfectly readable.
When i was testing a few blocks from the tower i played with the gain settings to get rid of the noise floor and it still didnt find the band plan or voice channels. I have some screenshots of all that and signal strength ill upload now. The signal couldn't get much better. i believe.
When i have all of the frequencies (listed for the system on RR) in 2 groups within 2mhz of each other, it still does not find the voice channel or any of the data displayed from the control channel. From what i can see the other frequencies listed in the system never have any activity or spikes on the waterfall. I havent tried programming the extra stations licensed to them yet but i will.
Im not sure if it matters but when is set iut to LSM it loops sync lost and when i switch to C4FM it logs normally. But the system is a simulcast with 2/3 nearby towers.
I have not yet seen a voice channel pop up or seen any decoded voice data. Im interested to see if it has to do with the p25 implentation you brought up. Is there a program that can handle tghe system if it implicit?
Thanks -steve
Prerunning
Jan 3, 2020, 12:45:20 AM1/3/20
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*the 2 pics in SDR# are to show the signal stregnth using the 2 cheapo antennas inside the house.
Dean Sauer
Jan 3, 2020, 8:11:51 AM1/3/20
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The images you posted... with NICE SPIKES, MUCH MUCH MUCH BETTER!
If you are close enough which it appears you may be the included antennas will suffice.. I leave it at, NOT A FAN.
I use only LMR antennas thats the same stuff I install and you see on towers, cars, portables.
Now something that has come to my mind, is that this system just may not be that "voice active."
You WILL SEE TONS OF MESSAGES in the MESSAGES tab... That is NORMAL. The CC sends out IDEN_UP_VU etc. message 100%/24/7/365, then as traffic occurs you will grants for voice, data, affiliations, deregister, rejects etc... The CC is NEVER IDLE! EVER! Unless you have a failure... The CC is VITAL TO TRUNKING OPERATIONS, or well OPERATIONS period.
Now what you need to do is:setup IN SDTRUNK ONE CHANNEL for each of the following:
https://wireless2.fcc.gov/UlsApp/UlsSearch/licenseFreqSum.jsp?keyLoc=15968043&licKey=3485831&archive=&x=10&y=9
155.235, 155.490, 155.700, 159.2175, 159.300
With 2 SDR's this shouldn't be an issue setup the 155's on one, the 159's on another.. P25 mode for each..
What you want to see is voice grants show up... by having them all going you can see the voice grants etc.. show up. .. click on each channel and it will show you the activity that has occurred on each... in the EVENTS tab.
These are the channels you need.. the OTHERS the FX1's are the INPUTS what the mobiles transmit on..
Since if you take these outputs and look a the inputs most of these are not a easily divisible by + - for EXPLICT setups ie: RFSS sends out a base, step, and offset of say +1...
SO they are using IMPLICT where the radios are programmed with the info, and when told to go to 2-182 they know what to do.. Hence why the RFSS details has not data.. the radios have the data..
The author will need to speak to how they deal or do not deal with IMPLICT on ly trunking on P25 on V/UHF....
This system could be very lightly used... ie: used only when needed and cell phones maybe used in place.. although I thinking that may not be a big option out there.. but in areas close back to towns it might be an option... But BIAPD's probably are not that active... so it may be awhile for a grant to show up.
Now that you got the signal up out of the noise let it run, with the other channels active and see what you get. It might be awhile....
As for other programs... really can't help... OP25 or SDRTrunk is all thats out there, as I am 100% Linux only. There have been other programs out there in the past for DOS etc.. which may/have evolved to be something more in the NON Linux area... If it don't run on Linux, I don't care. Have not touched anything else in 20+ years.
There may be gyrations and band aids to get some of that junk to run on a real OS via things like WINE layers etc.. Well the whole point of not using that stuff is I don't want the risks of that virii on my stuff, for one thing...
I am an OS snob, and I make no bones about it. There are 2 things I have no use for msloth and "that other" site.
So setup the voice channels, turn on the loggig, sit tight and see what shows up....
Prerunning
Jan 5, 2020, 3:30:41 AM1/5/20
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I let it run overnight listening to all 5 channels. There were several call events listed on the control channel history and i did see it switch from the CONTROL channel to CALL for just a couple seconds(on the same channel programmed to 155.235) but still no voice or any activity on the individual voice channels. The other 4 channels have 0 event history/and looping sync lost. Screen shots with calls/events
The low activity makes it a challenge to follow a call log on the control side and try to match it to any activity on the other 4. When im listening to all 5 channels, I can see a different system accurately keying on and off along with my base scanner but yet to see any activity on the voice channels.
I did find a few things in the logs that may be of interest. I updated my google drive with the full log folder but ill copy and paste the few lines i think may be important.
0191230 144320,FAILED,NAC:1802 TSBK3**CRC-FAILED** ID:0 OFFSET:-3879000 SPACING:53875 BASE:16111429925 FDMA BW:4000
20191230 144320,FAILED,NAC:1802 TSBK3**CRC-FAILED** VENDOR:V220 UNRECOGNIZED OSP OPCODE MSG:90DC0580FDBF8050B300F854
20191230 144320,PASSED,<-> SYNC LOSS - BITS PROCESSED [374]
20191230 144321,PASSED,NAC:1802 TSBK1 SYSTEM LOADING MOTOROLA MSG:89900000000000000000D289
In the Command Console that launches with SDRTrunk, the last line is this;
00:30:50.291 DEBUG i.g.d.m.d.p.p.P25P1DecoderState - Unrecognized AMBTC Opcode: ISP_AUTHENTICATION_QUERY_OBSOLETE
Also, this event doesn't look familiar. Im not sure if i just missed it before or possibly 1st time it has logged in the system.
QUEUED: OSP RESERVED 1 REASON: RESERVED INFO: 20600
I really like linux as well but compatibility is usually my issue and dealing with dependencies and root gets a bit old but my laptop always has a pen testing flavor with all the wifi goodies. I can switch to linux software and try again but not sure it would help anything with this issue. op25 was the end goal based on comments in the forums, but i figured itd be best to play with sdrs in windows before diving into the linux config.
Unrelated question you may be able to answer for me. Im trying to listen to an analog dispatch channel. It uses a ctcss tone. Im able to see it in the waterfall but yet to hear it. When i was using sdr# it was able to detect the correct tone but i was never able to hear anything except static. Possibly a software limitation or bad config maybe bandwidth? Not sure if you can shed any light on that.
Thanks again for helping. Its much appreciated! -steve
Dean Sauer
Jan 5, 2020, 6:41:00 AM1/5/20
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On Sunday, January 5, 2020 at 3:30:41 AM UTC-5, Prerunning wrote:
I let it run overnight listening to all 5 channels. There were several call events listed on the control channel history and i did see it switch from the CONTROL channel to CALL for just a couple seconds(on the same channel programmed to 155.235) but still no voice or any activity on the individual voice channels. The other 4 channels have 0 event history/and looping sync lost. Screen shots with calls/events
In THIS system there is NO NEED for the CC to used for voice traffic... They have 4 channels for 4 voice...or data calls... CAN you do this? YES. Its something that EDACS did/does called SCAT - Single Channel Trunking. Low, like really low volume sites in rural areas would get ONE tower with one channel it pumped out CC till a unit was in the area and needed to do a voice call... You can do this with P25 too.. it makes no sense with 4 other channels... Could you still do it? Sure... why? If in the case of something loading wise you needed it .. sure...
This is actually a SIGN of A PROBLEM.. for you... more in a minute...
The low activity makes it a challenge to follow a call log on the control side and try to match it to any activity on the other 4. When im listening to all 5 channels, I can see a different system accurately keying on and off along with my base scanner but yet to see any activity on the voice channels.
See your screen shots.. units registering and affiliating...and stuff.. This along with the snippet below is an issue...
I did find a few things in the logs that may be of interest. I updated my google drive with the full log folder but ill copy and paste the few lines i think may be important.0191230 144320,FAILED,NAC:1802 TSBK3**CRC-FAILED** ID:0 OFFSET:-3879000 SPACING:53875 BASE:16111429925 FDMA BW:400020191230 144320,FAILED,NAC:1802 TSBK3**CRC-FAILED** VENDOR:V220 UNRECOGNIZED OSP OPCODE MSG:90DC0580FDBF8050B300F85420191230 144320,PASSED,<-> SYNC LOSS - BITS PROCESSED [374]20191230 144321,PASSED,NAC:1802 TSBK1 SYSTEM LOADING MOTOROLA MSG:89900000000000000000D289
You don't want to see CRC FAILED! EVER. Sure a few sporadic ones now and then its RF, it happens.. no big deal..
This is a good sign of two things...
You need to LOWER THE MASTER GAIN a little and/or MOVE POSITION OF Antenna's.. Especially in a simulcast system...
BUT BEFoRE YOU do that..
If you switch from C4FM to LSM with the signal as a nice spike does the CC drop out ie: no longer decodes still????
How far away are the other sites from you? air miles not driving.
In the Command Console that launches with SDRTrunk, the last line is this;00:30:50.291 DEBUG i.g.d.m.d.p.p.P25P1DecoderState - Unrecognized AMBTC Opcode: ISP_AUTHENTICATION_QUERY_OBSOLETE
Not something you want to see...
This and the data you are seeing on the CC indicate ****** >>>> to me <<<<< **** that maybe there are some variances in the CC packets for V/UHF that SDRTrunk is not setup for yet... the author will need to address those.
I think this thing is using IMPLICT ONLY thus the SDRTrunk needs to know that channel 2-182 is 155.235 etc.. and I don't know of a way to do that??? Author will need to reply...
Coupled with there may be signal issues you need to deal with and missing options in the CC data decoder for this setup...
Also, this event doesn't look familiar. Im not sure if i just missed it before or possibly 1st time it has logged in the system.QUEUED: OSP RESERVED 1 REASON: RESERVED INFO: 20600
Ditto.
I really like linux as well but compatibility is usually my issue and dealing with dependencies and root gets a bit old but my laptop always has a pen testing flavor with all the wifi goodies. I can switch to linux software and try again but not sure it would help anything with this issue.
Switching in re SDRTrunk will make little difference...
I think there may be some issues with IMPLICIT ONLY trunking in SDRTrunk and that will have to be addressed by the author...
I also think that some fine tuning is needed on YOUR SIDE to get the signal optimized to ensure non CRC errors etc...
I looked at that link you gave.. and while interesting especially v. the Hydra 4 SDR units at $150! I have to wonder if the mods are not making things worse?? I actually might get one just to see what they do around here... The marketing schtick.. I am not fond of! SCREAMS SCAMMER! Again PERSONALLY the antennas on those things are JUNK... I rather take a nice VHF mobile with a ground plane kit or even stuck on a PIZZA PAN with an NMO Mag mount than those junky things.. AGAIN PERSONAL PREFERENCE. If you are close enough, which if your are able to drive to the actual site, then you probably are.. then it shouldn't make a difference unless your home has issues, ie: HIGH POWER VHF traffic nearby, home construction ie: concrete walls, UV coating on windows, metal roofs etc.. I'd definitely if possible want this near a window... now I say that, let me tell you that when I used something else to monitor a P25 system early on finding the "sweet spot" was not near a window....RF is a fickle beast and alot of things that you should do x,y,z are often broken in some cases.. RF bounce, wall construction etc..
As for Linux compatibility, in 20+ years the only thing I can think of an run into is some very specific video processing programs don't exist in Linux which is hilarious in a way...
As for dependencies... don't use RedHat or RPM based distros! That will save you 99.99999% of the issues right there! The RPM system is garbage! Debian poses a problem for its stupid DFSG BS... Ubunutu's clean up **most** of that... there still some of it.. 99.999999999999999999999999% I just do a sudo apt-get install GreatSoftware and get on with life.. maybe I need to grab it from a different PPA by adding it or just a raw DEB package and do a sudo dpkg -i OttherGreatSoftware.deb
Let me just keep this a little SDRTrunk related.. because of LINUX I can run SDRTrunk on a box in a data room and see it on my local box... and I am sure the keyboard warriors are ready to reply.. you can do that with RDP... yes you can, but thats bloated.. I've got several programs open and basically the X system allows the screen to be sent out the network to,well, whereever. its how I work.. 100's-1000's miles form where stuff is. :) X Forwarding has been around longer than another piece of "software" has even been around.
And alot of places have got their heads out of their posteriors in re Linux and offer packages for it. As well as ALL Linux improving immensely from the early days on software installs.
I've had very few issues in this, and when I do its on RPM based crap.. which is why I got rid of it unless I have to have CPanel.. and now with CPanel killing the goose with their horrific license fees they are going to end the need for that too!
Thats pretty much enough really for me to rant .. as its not germaine to this list or issue...
op25 was the end goal based on comments in the forums, but i figured itd be best to play with sdrs in windows before diving into the linux config.
Op25 can be setup or well COULD be easily setup till the monkeys broke something in the tutorials.. I could outline, but again, offtopic really, . now you need to do some gyrations that are above the average user to get the right program in place to compile it...
OP25 is great in that it does PHII which I need for 2 systems.... its a even bigger behometh due to its reliance on GNU Radio... at least space wise.. it runs on Pi's which great in some ways and crap in others.. The big issue with a new system is watching what they are doing, with SDRTrunk I can do that easily.. versus digging through logs MB's long and full of useless data for 90% of the stuff.
Once the kinks on PII are worked out the P's are going! Or going to something else at least... SDRTrunk will be used for all 4 systems.
Unrelated question you may be able to answer for me. Im trying to listen to an analog dispatch channel. It uses a ctcss tone. Im able to see it in the waterfall but yet to hear it. When i was using sdr# it was able to detect the correct tone but i was never able to hear anything except static. Possibly a software limitation or bad config maybe bandwidth? Not sure if you can shed any light on that.
If you program it into SDRTrunk as a NBFM or a P25 channel then you can hear it if its analog or P25.. You can't program the PL/CTCSS tone in and there is no SQUELCH either for NBFM so you would hear static the entire time is not in use ...
How far away is this signal??? Is it a repeater output? Or a simplex, base and mobiles channel???
Remind me again, you programmed in the NWR channels in SDRTRunk and they worked? Right???
Issues like this keep pointing back to either issues with the SDR(s) or antennas....Can you hear this analog signal on the BCT15?????
Dean Sauer
Jan 15, 2020, 7:37:50 PM1/15/20
to sdrtrunk
On Friday, January 3, 2020 at 12:39:45 AM UTC-5, Prerunning wrote:
This is a link to the 2 sdr unit and antennas it came with.
OK.. I got one of these in todays parts delivery.... and initial thing I ran into.. connecting the MCX antenna...
the sdr boards inside moved, at least on mine.. too much for the MCX connector to "snap" into place...
So first thing first.. I would suggest that what ever you are connecting to the MXC connector on these..
UNSCREW the ends of the case and with a NON METALLIC item... and USING PROPER STATIC GROUNDING PROCEDURES!!! Wristrap. mat, etc.. if you don't know what these are STOP! Don't have these items STOP!
Using the non metallic, like a coil tuning tool, hold the PCB firm and SNAP the MCX connector onto each connector.. you should physically feel it sort of snap tight and snug...
Second, thing.. along with all the little goodies.. if you got one of those USB splitter/combiners... and are using it.. REMOVE IT! Connect to TWO USB ports.. and if you know which ports go to different USB hubs on the MB use different ones. if possible...
I am not saying this is the 100% cure to things.. but its a GOOD start.. you want a GOOD CONNECTION! With out these snapping tight you are incurring loss. and even with a strong signal could be a source of problems...
So double check those connections, and remove that USB splitter/combiner if you are using it... rerun things see what happens..... I'll post my experiences with mine later... my gut still say this is an issue in explicit v. implicit trunking...
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