AR8200 D - Listening to P25 Digitial

[kett]

Many thanks "prcguy" and "Boatanchor" for your prompt replies. You have confirmed that (at least) I am enabling P25 decoding correctly. The good news is that I have today just started to hear some decoded CFA voice transmissions, but as you have advised "Boatanchor", I guess some of these "CFA P25" frequencies I am scanning through are those "trunking control data channels" you mention. Not good news for my intended use, I guess, but I really appreciate the info you have shared with me.
Merry Christmas, Kett.

 

[Boatanchor]

Kett, on a positive note, all you really have to do is find out what the voice traffic channels/frequencies are on your local RMR trunking sites and enter those channels into a scan bank.

You can use this site:

RMR Network Sites | Vicradio Zone

Ignore the control channel frequencies (the first/top frequency in each site) and only enter the voice channels for your nearby sites. The scanner will only stop on the voice channels if they become active and you should hear all the CFA dispatch activity, assuming there is/are CFA units affiliated with those sites.

Honestly though, I would consider selling the AOR and purchasing a BCD396XT scanner instead.
It would be much more appropriate for your needs and half the size

 

[kett]

AR8200 D - still learning

Thanks yet again Boatanchor. It is heartening news to hear you say that I can probably get some "joy" by just ignoring the Control Channels. Also thankyou for the reference to Vicradio Zone - it has been the source of most of my (limited) knowledge on P25 to date. I am about to delete/skip each of the CCs I have Programmed at present, and see how I go with that.
Oh, one other question (if I be so bold) - does the number setting (V nnn) in the Voice Inverter (enabled when P25 is enabled) have any bearing on the P25 decoding performance?
BTW I appreciate your comment re going to a BCD396XT, but just now I don't think that suggestion would go over too well with "santa"!! (Reminds me of your quote -" What can go wrong, will inevitably go wrong.") - You got that right!!
Cheers, Kett

 

[Boatanchor]

At the moment, CfA are pretty much the only RMR users in rural Victoria, so any traffic you hear is likely to be them and voice channel only scanning should work fine for you.

The problems will start when other agencies start migrating across to the RMR like the Ambo's, SES, DSE/NRE, Vicroads and others. The AOR will not be capable of isolating one agency/user on the system and you will hear comms from multiple agencies. Without trunk tracking/talkgroup scanning, it may start to get confusing as to what you are actually listening to, or you may end up hearing a lot of traffic that you are not interested in (potentially missing CFA traffic on one of the other voice channels).

Sorry, I'm not familiar with the AOR implementation of P25, so I can't comment on your settings question.

 

[Boatanchor]

I'm just guessing at this point in time, but one of the primary settings in any P25 system is the 'NAC'. The Network Access Code is a three digit code that defines the access code for the repeater/site.
It is possible that '(V nnn)' refers to the NAC and allows you to specify a NAC, which is a bit like a CTCSS code equivalent in P25 systems.

I'm unsure as to whether you have to specify a NAC in the AOR, or whether you can just leave this blank. If you do need to specify a NAC, I suggest you use 'F7E', which will force the receivers digital mute to open on all received NAC 'codes'.

 

[prcguy]

The AOR 8200 does not need a NAC, it just receives whatever is on frequency when in P25 mode.
prcguy

I'm just guessing at this point in time, but one of the primary settings in any P25 system is the 'NAC'. The Network Access Code is a three digit code that defines the access code for the repeater/site.
It is possible that '(V nnn)' refers to the NAC and allows you to specify a NAC, which is a bit like a CTCSS code equivalent in P25 systems.

I'm unsure as to whether you have to specify a NAC in the AOR, or whether you can just leave this blank. If you do need to specify a NAC, I suggest you use 'F7E', which will force the receivers digital mute to open on all received NAC 'codes'.

 

[kett]

AR8200 D - still learning ....more

Thanks guys for your further assistance. I get where you were coming from Boatanchor with the NAC suggestion, but I guess prcguy has the"goods" on us with his knowledge of the AR8200D.

I would still appreciate your comment prcguy on whether the Voice Inverter "V nnn" number does have any bearing in the successful decoding of P25. I have found over the past 24 hours while scanning for (only) the voice channels on the CFA (Country Fire Authority) P25 network that my success in hearing decoded voice traffic has been very "patchy" at best. This seems pretty much independent of whether the received RF signal level is low/medium or even quite strong.

I have taken "on-board" your comments, Boatanchor, as to how the traffic in my area may change as more organisations start using the RMR. In these "early days" of listening to P25 for me, I will just have to take things as they come, so to speak.

Kett.

 

[prcguy]

The number selection for the vioce inversion descrambler does not affect P25 decoding.
prcguy

Thanks guys for your further assistance. I get where you were coming from Boatanchor with the NAC suggestion, but I guess prcguy has the"goods" on us with his knowledge of the AR8200D.

I would still appreciate your comment prcguy on whether the Voice Inverter "V nnn" number does have any bearing in the successful decoding of P25. I have found over the past 24 hours while scanning for (only) the voice channels on the CFA (Country Fire Authority) P25 network that my success in hearing decoded voice traffic has been very "patchy" at best. This seems pretty much independent of whether the received RF signal level is low/medium or even quite strong.

I have taken "on-board" your comments, Boatanchor, as to how the traffic in my area may change as more organisations start using the RMR. In these "early days" of listening to P25 for me, I will just have to take things as they come, so to speak.

Kett.

 

[Boatanchor]

Sorry, I thought the setting in question was only available once P25 was enabled.
That is why I figured it was related to NAC - Obviously not though.

Seems a bit odd that an analogue voice inversion setting would be accessible in P25 mode.

It will be interesting to find out if kett has the same problems with the TDU packets not muting correctly on the AOR.

Let us know how you go Kett.

I'm 'mildly' interested in the upcoming AOR DV1 or whatever it is called. But without trunk tracking, I may as well use SDR and DSD+ to do pretty much the same thing for a fraction of the price. The DV1's main competitive edge may be it's RF performance though.

 

[kett]

Thanks for your answer re the numbers for the Voice Inverter Descrambler when on P25, prcguy. That is what I guessed but I appreciate the confirmation - 1 less thing to worry about!
Now Boatanchor, I suspect that the bug you and prcguy discussed at the start of this post, regarding the possibility that the AR8200D is not muting the TDU data, is exactly what is occurring in my reception. I will definitely let you know after I have had a couple more days to "fiddle". And, if we agree that is what is happening, I will certainly be asking some hard questions of AOR!!! I'll keep you posted.
Kett

 

[kett]

Well I've been "playing" with listening to local P25 (CFA) traffic on and off, and it seems (albeit a little spasmotic) that sometimes I will hear what I guess is TDU data and the radio will mute nicely. On many other occasions it just continues to stay unmuted with an almost continuous stream of data(?) "noise". When it behaves "properly" the audio is mostly crystal clear, quite high level (compared to analogue received at the same setting), and a pleasure to listen to!
Anyway, I have emailed my supplier informing them of my misgivings, and seeking any assistance they may be able to give me. I will post further after I receive an answer!!
Kett

 

[kett]

Firmware Update . .

Well here we are a month into 2015 already, and I can report that I now have my AR 8200 D back working in a much improved manner to when I last posted. As a result of my communication with my "local" supplier, they arranged for AOR (Japan) to install a "Firmware Update" to my unit to improve its performance on receiving P25 transmissions. Although still early days, it seems to be like a "different beast".

It now appears to mute on any data streams, but open up to provide pretty well crystal-clear audio, when some audio traffic does occur. I have learned that a strong signal is imperative for satisfactory performance, but am still checking this point, as on some occasions a "full bars" signal still does not decode reliably, while on others, a "half bars" signal results in good clear audio(?).

I do commend AOR and my supplier for attending in a timely, helpful manner to my concerns, and AOR have advised that all AR 8200 Ds in future will ship with the firmware now in my unit. It is just a pity that they were not perhaps a little more pro-active in advising all owners (or at least suppliers) that this mod was necessary to (more) reliably decode P25. A downside is that when scanning (most of the time for me at present) any strong (open squelch) signal due to data traffic will stop the scan. AOR have advised me that this is expected behaviour!!

I am a much happier punter now - but still should have bought a Trunk Tracker for my main intended use. Oh, well you live and learn.

Cheers again, Ian

 

[Boatanchor]

Kett, did you have to send your unit back to Japan/US for the P25 module firmware update?

 

[kett]

Hi Boatanchor, I did not need to send my unit to Japan/US, and I thought I had sent you a private message to advise you how to get more details(?) If you didn't receive it please let me know here, and perhaps give me a method of communicating "off-line", if you want more details.

Kett

 

[prcguy]

Ian,
Thanks very much for posting the firmware info. I contacted the AOR US representative and they are unaware of any recent firmware upgrade for the 8200D. Do you have a firmware rev # or something I can tell them to look for?
prcguy

Well here we are a month into 2015 already, and I can report that I now have my AR 8200 D back working in a much improved manner to when I last posted. As a result of my communication with my "local" supplier, they arranged for AOR (Japan) to install a "Firmware Update" to my unit to improve its performance on receiving P25 transmissions. Although still early days, it seems to be like a "different beast".

It now appears to mute on any data streams, but open up to provide pretty well crystal-clear audio, when some audio traffic does occur. I have learned that a strong signal is imperative for satisfactory performance, but am still checking this point, as on some occasions a "full bars" signal still does not decode reliably, while on others, a "half bars" signal results in good clear audio(?).

I do commend AOR and my supplier for attending in a timely, helpful manner to my concerns, and AOR have advised that all AR 8200 Ds in future will ship with the firmware now in my unit. It is just a pity that they were not perhaps a little more pro-active in advising all owners (or at least suppliers) that this mod was necessary to (more) reliably decode P25. A downside is that when scanning (most of the time for me at present) any strong (open squelch) signal due to data traffic will stop the scan. AOR have advised me that this is expected behaviour!!

I am a much happier punter now - but still should have bought a Trunk Tracker for my main intended use. Oh, well you live and learn.

Cheers again, Ian

 

[kett]

Hi prcguy,

I do not have a rev# as such, but it may be worth mentioning to AOR (US) the reference "AR82D004".
Mind you, I don't know how "recent" this firmware update is? I just know that my radio as delivered did not have it.
If this info does not prove to be useful, I suggest 2 possibilities. 1. Send me a private message, and I can probably give you a little more info, or 2. Send an email to Mr Frederic Collin at AOR (Japan) - mail@aorja.com - asking for assistance with any updates available around the end of 2014.
Hope this helps, Kett

 

[prcguy]

Thanks! Email sent to AOR Japan and I'll post the outcome of this adventure.
prcguy

Hi prcguy,

I do not have a rev# as such, but it may be worth mentioning to AOR (US) the reference "AR82D004".
Mind you, I don't know how "recent" this firmware update is? I just know that my radio as delivered did not have it.
If this info does not prove to be useful, I suggest 2 possibilities. 1. Send me a private message, and I can probably give you a little more info, or 2. Send an email to Mr Frederic Collin at AOR (Japan) - mail@aorja.com - asking for assistance with any updates available around the end of 2014.
Hope this helps, Kett

 

[prcguy]

I received updated software from AOR Japan and it seems to fix a problem where you hear digital data sounds during the repeater hang time on some P25 systems. Mr. Collin at AOR Japan was extremely helpful and quick to provide information. AOR US in Torrance, CA is unaware of this new firmware and is not so good with supplying information

I also inquired about increased birdies and overall reduced performance in the 480 to 512MHz spectrum using a rubber duckie antenna after my 8200MK-3 was upgraded to an 8200D. When searching or scanning this range the S meter is usually at half or full scale with no signal present and when receiving in this range, other P25 scanners with the same antenna work much better.

It appears the new board that comes with a P25 upgrade is generating interference and affecting performance. Using an external antenna far away from the receiver reduces or eliminates the interference. AOR Japan says this is to be expected and if I had to do it over again, I would not get the P25 upgrade.
prcguy

 

[freqseek]

I was denied by Mr. Collins a few weeks ago,because I purchased mine before the D model was available in states. therefor they refused to support my receiver.
They did give me the DMR firmware update for the ARD300, which I was amazed how much DMR signals there are out their.
The ARD300 hook up to the AR5001D will have the annoying Data coming through also on P25 & D-star unless you turn down volume all the way on the receiver which prevent you from listening to analog signals while scanning.
thought I would add my 2 cents