Test for P25 Decode Improvement

[cjabass123]

This is in reqard to P25 ANALYZE functionality. Forgive me if I repeat someone else's wish. And I apologize if what I'm suggesting is way off base.

It seems the AUTO mode is working for some and not others. Some say the auto adjustments are so aggressive that it causes audio quality to go from good to bad (and perhaps back again). Some have suggested allowing the user to have some input, such as setting a smaller range of adjustment (ie 3 - 5 or 6 - 9) instead of having the radio test from 0 - 9 every time. And I think we need a simple quick way to save the settings, once we identify them.

So I guess what I am requesting is a SMART AUTO mode. Here's how I'd like to see it work:

I apply the new firmware and go into SMART AUTO ANALYZE for the first time. I HOLD on a channel. I say ANALYZE. The ALERT light is RED. As the radio performs it's adjustments, as the error rates improve the ALERT light begins to go to YELLOW and when the alert light gets to GREEN, I hit a button and the radio changes it's settings (saves them) and sets the mode to MANUAL for that channel. If I ever go into analyze mode for that channel again, I'll see the alert light is green (because it's been set to MANUAL) and know that the radio has already been set for that channel.

Perhaps part of its adjustment could also be to test both FM and NFM modulation settings.

I am not saying it's impossible but it seems that getting clean P25 audio adjustments, on-the-fly, automatically, may simply not be realistic. (Though GRE users seem to be very happy) That's not a slam against Uniden. They're certainly working on it. But until such time as they nail it, perhaps the user can help if Uniden gives us a method to do so.

Once I find a good P25 setting for a system, dept, or channel, I'd like to know that I'm done with it and not have the radio try to re-adjust it every time, causing me to lose the audio stability that I may have already saved.

As a former programmer, I know that if all the data and parameters are present, anything can be accomplished.

 

[cjabass123]

Initial test of 536 with new firmware;

US > Florida > Broward (County) > Broward County Public Services
Broward county, Boca Raton
Condition before: poor/good
Condition after: good/excellent

US > Florida > Broward (County) > Palm Beach County Public Services
Palm Beach county, Boynton Beach PD, DelRay
Condition before: poor/good
Condition after: good/excellent

US > Florida > Broward (County) > Martin County Public Services
Martin county Sherriff
Condition before: poor/good
Condition after: good/excellent

I know these results are varying from person to person, but I am pleased to report that my recent excursion up I-95 in south Florida yielded good digital decode results from the systems noted above. To me, it was a noticeable improvement over the numerous previous trips through those areas.

 

[cjabass123]

I would also like to add a caveat to my results. I have recently added a 700 - 860 MHz bandpass filter behind the radio (inline w/ coax obviously). The filter has very sharp attenuation just after 860 mhz. This has eliminated and/or significantly reduced much of the cell tower interference that has for years been a royal pain-in-my-850mhz-reception-a_s!!!!

There are many towers in the urban south FL area and I am sure that some of the poor digital decode in the past was at least also partially due to tower interference because the towers affected non-digital reception as well. So, together with the new firmware, the filter has made my listening life a whole lot more enjoyable. Since installing the filter, not one tower that used to regularly and consistently crush my reception is able to do so anymore. Even the worst offenders are only able to make a small impact on reception/audio quality, which is very acceptable. Now, what little interference is left, sounds about like what you would encounter from a moderately weak signal, a little scratch, but intelligible.

FYI: If you're thinking about getting a filter, RESEARCH and UNDERSTAND the specs. Filters vary WIDELY in the amount of attenuation and the sharpness of frequency response at the fringes. I know Scanner Master sells filters, but I was unsuccessful at getting them to give me any specs on them so I did NOT purchase from them. I got mine off eBay from a seller in Israel, who included the spectrum analysis chart in the listing. (They were also MUCH cheaper). And they WORK!

 

[jimwidman]

SLATER: St. Louis Area Trunked Emergency Radio - SLATER (P25) Trunking System, St Louis Metro Area, Multi-State - Scanner Frequencies
SPECIFICALLY: StL County - Urban South [P2] Site Details (St. Louis Area Trunked Emergency Radio - SLATER (P25))
BEFORE: average would like it to be better
AFTER: worse

Thank you for the support.

 

[Theo]

I would also like to add a caveat to my results. I have recently added a 700 - 860 MHz bandpass filter behind the radio (inline w/ coax obviously). The filter has very sharp attenuation just after 860 mhz. This has eliminated and/or significantly reduced much of the cell tower interference that has for years been a royal pain-in-my-850mhz-reception-a_s!!!!

There are many towers in the urban south FL area and I am sure that some of the poor digital decode in the past was at least also partially due to tower interference because the towers affected non-digital reception as well. So, together with the new firmware, the filter has made my listening life a whole lot more enjoyable. Since installing the filter, not one tower that used to regularly and consistently crush my reception is able to do so anymore. Even the worst offenders are only able to make a small impact on reception/audio quality, which is very acceptable. Now, what little interference is left, sounds about like what you would encounter from a moderately weak signal, a little scratch, but intelligible.

FYI: If you're thinking about getting a filter, RESEARCH and UNDERSTAND the specs. Filters vary WIDELY in the amount of attenuation and the sharpness of frequency response at the fringes. I know Scanner Master sells filters, but I was unsuccessful at getting them to give me any specs on them so I did NOT purchase from them. I got mine off eBay from a seller in Israel, who included the spectrum analysis chart in the listing. (They were also MUCH cheaper). And they WORK!

What filter did you actually get ?

 

[cjabass123]

It is a 700-860 bandpass filter. If you search "bandpass filter", look for the seller from Israel. He/they have a ton of listings on there. You can try narrowing the search using 700 or 860 as an additional search filter. They are about the size of a long cigarette with female SMA connectors so you'll need some coax adapters possibly and those are plentiful on ebay as well. Your whole setup will be much cheaper than a filter from scanner master. Their filter might be great also. I don't know. Twice I have emailed them for specs about their filter but never got a reply. I won't spend money on something I have no specs on nor do business with someone who doesn't respond to attempts to contact them. I can attest that the filter from the Iraeli ebay seller works! At the time of my previous post, he still had some available. Sorry for the delay in replying. I have been out of touch for awhile.

 

[Theo]

It is a 700-860 bandpass filter. If you search "bandpass filter", look for the seller from Israel. He/they have a ton of listings on there. You can try narrowing the search using 700 or 860 as an additional search filter. They are about the size of a long cigarette with female SMA connectors so you'll need some coax adapters possibly and those are plentiful on ebay as well. Your whole setup will be much cheaper than a filter from scanner master. Their filter might be great also. I don't know. Twice I have emailed them for specs about their filter but never got a reply. I won't spend money on something I have no specs on nor do business with someone who doesn't respond to attempts to contact them. I can attest that the filter from the Iraeli ebay seller works! At the time of my previous post, he still had some available. Sorry for the delay in replying. I have been out of touch for awhile.

I found it. Got the last one! Just waiting for some SMA adapters to try it. Thanks.

 

[cjabass123]

Awesome! Whew... I'm glad I decided to visit the forum today and chime in. Congrats!

 

[cjabass123]

I also just picked up a couple of coax relays and a couple more adapters/jumpers so that I can switch from filtered to unfiltered at the push of a button. So that whenever I am travelling into VHF/UHF territory, I'll be able to hear all freqs. If, at any time, I am receiving a 850mhz signal and I see a tower or begin getting some interference, I can just push the button to switch back to the filter and hopefully knock it down. This setup requires the use of two 15v relays and one on-off-on mometary switch. If you use two antennas, only one relay would be necessary. For the record, an electrical engineer friend of mine, who is a military communications expert and also is a ham operator, masterminded this setup. And happily the components were cheap. I'm waiting on one jumper cable to arrive to complete the setup. I'll report on the results.

 

[fmulder13]

Maine State Communications Network (MSCommNet) Trunking System, Statewide, Maine - Scanner Frequencies
Site: Cook Hill
Before: 436hp would not receive anything in ID Scan, would only receive a few transmissions when holding on a talkgroup
After: Receives transmissions in ID Scan or holding on a talkgroup, but misses the following 2-3 seconds of the subsequent transmission(s), picking them up late or missing them while a GRE scanner catches everything.

Decode quality, when audio is actually being received, is/was flawless before and after.

 

[mjs438]

US >Philadelphia (Project 25) > Police

Condition before: Good/Poor
Condition after: Poor/Poor

 

[pingdew]

Michigan's Public Safety Communications System (MPSCS) Trunking System, Statewide, Multi-State - Scanner Frequencies
TG3141 Dec (Mostly, but whatever TG in that county that came through for about 30 minutes)
Condition before(NFM): Good
Condition after(FM): Better but not outstanding

I monitored only Van Buren County. I liked the improvement but feel I need to do more than 30 minutes on each to be certain.

 

[n1chu]

Virginia Beach, Virginia; I was visiting for a military air show, my primary interest was with conventional military air freqs. But at times other than the air show, I would listen to VB public safety, a P25 system. It would constantly drop out, clipping off the transmissions. Not overly concerned with this secondary monitoring, I did not think to engage the attenuator or set the AGC, never mind the NFM/FM setting. But if I were to guess, I think activating the attenuator would have fixed the problem. I was doing my monitoring from 21 stories up atop the hotel roof/pool deck, giving the scanner a good look at probably every repeater site the system uses. Mental note to myself for next VB visit-expirement with these settings.

 

[Voyager]

The dropping out may have been the Channel Priority, Weather Priority, or Close Call (if not in DND mode).

 

[SCPD]

Gentlemen, please keep in mind that this thread is for reporting the results of your testing using the following format:

To submit a report:
FORMAT FOR REPORTING (to make my life a little easier):
Link to the system in RRDB.
Specific site monitored (if known).
Condition before: Excellent / Poor
Condition after: Excellent / Poor

Does this apply to P25 conventional? I trust the band defaults only apply if you set your channel modulation to AUTO, correct?

So I shall trying forcing FM instead of NFM on my test case -- a VHF P25 frequency.

 

[SCPD]

Washington State Patrol Scanner Frequencies and Radio Frequency Reference

Conventional P25 VHF (Washington State Patrol)
District 2 Dispatch 155.58 Mhz

Condition before: Poor
Condition after: Excellent

Condition Before notes: Missing conversations. Decode would only be about 50% when HOLDING single channel. (Same in scanning mode too.)
Condition After notes: Hearing exact decode compared to XTS 5000

Both radios are using rubber ducks less than 1.5 miles from WSP HQ in Bellevue.

Forced FM mode from NFM.

 

[slwilson28625]

Rather than try to post these details in several threads, I'm making one post and hoping you'll see it (and maybe post in the thread you were previously active in pointing here). We've been investigating the various reports of degraded P25 performance in some areas and noted with interest when reports surfaced that changing from NFM to FM mode improved P25 decode performance. We have tentatively verified this, but would like some more confirmation if you don't mind. Here is a relatively easy way to check:

First do MENU --> SETTINGS --> BAND DEFAULTS
Then, scroll to the setting(s) that have the frequency just below the range your local system is using. For example, if you are monitoring an 800 MHz system, scroll to the line that looks like:
849.0:NFM/ 12.5 MHz
Press E and scroll to change NFM to FM.
Press E two more times.
Then, check to see if there was any performance improvement.

For conventional P25, you'll still need to set MOD for the individual channels.

Based on the feedback we get from this, we'll be able to make adjustments that should reflect optimum settings w/o you having to tweak around with these settings.

Oh, and if your P25 decode is just fine, please do the above and see if it degrades your decode performance. We don't want to issue an update that fixes half of you but breaks the other half.

To submit a report:
FORMAT FOR REPORTING (to make my life a little easier):
Link to the system in RRDB.
Specific site monitored (if known).
Condition before: Excellent / Poor
Condition after: Excellent / Poor

Then, put any additional discussion you want to add.

UP[Man.......This thread started 02/20/15. With your testing and the information from this thread has Uniden made any determination if this is a worthwhile update to our units. I just wondered what the status is at this point. Thanks.

 

[Voyager]

Most people found improvement of the decode with the last version of firmware. A few found it was worse.

 

[ecarvalho]

BCD536HP Garbled audio / not following conversations

This is an old thread but I think my 536 is having audio issues on our Loudoun County (Virginia) P25.
We have good signal and all but audio is garbled and seems the radio is not keeping up / following the conversations as I only get bits and pieces of transmissions.

You can hear my most recent recordings here:
DROPBOX SHARED LINK:
https://www.dropbox.com/sh/i1vrnh4zb5io44b/AAA9z7Opd1T1ZGzS6eRp0hCaa?dl=0

For now, I will try switching to FM on a channel (Dulles Dispatch) which is the worst at this time and later report back.

Note: If there is any other fix please let me know.
Firmware: 1.10.02

 

[KE4ZNR]

Try this just for the heck of it:
--Edit the Favorites List where the Loudoun County system is stored.
--Highlight System then select "OPTIONS" tab.
--Turn Digital AGC Off.
Save then write changes back to scanner.
See if that improves audio quality.
Marshall KE4ZNR

This is an old thread but I think my 536 is having audio issues on our Loudoun County (Virginia) P25.
We have good signal and all but audio is garbled and seems the radio is not keeping up / following the conversations as I only get bits and pieces of transmissions.

You can hear my most recent recordings here:
DROPBOX SHARED LINK:
https://www.dropbox.com/sh/ny2xk73g69n5p6o/AAA--b8YOC9l_b5_A3Wts5OEa?dl=0

For now, I will try switching to FM on a channel (Dulles Dispatch) which is the worst at this time and later report back.

Note: If there is any other fix please let me know.
Firmware: 1.10.02