396T P25 decoding delay

[pboy]

You'll notice an additional line in the BCD396T features - Automatic P25 Decode Level. That links to the table and a discussion of how to use it. In particular, near the bottom, Dan discusses how to eliminate that little digital burst - it might help people using firmware 1.08 who have the problem. (Someone with a more artistic soul than I have might want to make it look nicer.)

The tighter threshold setting idea sounded like it had merit, however no luck.

There must be some kind of delay between when the scanner unmutes and the actual decoded audio begins.

 

[Voyager]

I thought I'd read that somewhere before... and I figured as much. I just thought that maybe he could give a general overview that wouldn't give away too much info. Besides, if GRE had a patent on it, wouldn't it be public information? Just curious.

Rob

Patent or not, there are agreements that you enter into with employers that prohibit you from divulging things - even if they can be found elsewhere. Motorola's trunking protocols were published (pre-trunker). Does that mean their engineers can give info out about them? Or would answer any questions about them no matter how trivial?

There are many things other people know that Paul surely knows as well, but can't confirm due to his employment position or confidentiality agreements (current or past). Sure, he could say, but why risk his job or a lawsuit from a previous employer? I'm sure nobody here wants to see that happen.

Joe M.

 

[Voyager]

It appears that it is only happening on 3600 mixed mode with the APCO-25 Common Air Interface. Clean ,full strength signals are affected.

It is not a decoder tuning issue.

Recovered audio sounds fine. Does not chop. Nothing missed at conversation start. Just a burst at the beginning of transmissions. Like something that should be muted is not being muted.

UPMan's tuning instructions do nothing for this.

Why the problem became worse with the firmware upgrade is a mystery.

Is your Close Call on? That can cause what you describe since you may be entering the conversation 'mid-frame'.

Joe M.

 

[Jay911]

Apologies for jumping in late..

Also: Does this happen on P25 audio on a P16 system, or just on P25 systems?

I can confirm that the P25 audio on 753f (Calgary's P16 system) is 'wonky' to use the technical term. I'm not necessarily experiencing late P25 decode as I am intermittent, if at all, P25 decode. When it does actually get to decode something, when I am very close to a tower site, it seems to cut in/out on a rather quick cycle, i.e. 0.25 seconds on/0.25 seconds off (but admittedly nothing quite so strict - seems more random, but it's definitely not "a second"). When I say "on" and "off" in that last sentence, "on" means hearing the decoded voice transmission and "off" means the digital P25 noise.

I am going to try to stuff the earlier firmware back in tonight at work and see if it behaves any better.

 

[w8mkh]

I have done the upgrade and it has not had any effect on our local p-25 still sounds the same.
Also the MARCS system sounds the same .
Hope you figure it out
73

 

[pboy]

Is your Close Call on? That can cause what you describe since you may be entering the conversation 'mid-frame'.

Joe M.

Close Call is not on.

Curious what "mid frame" would be.

Thanks.

 

[Al42]

Curious what "mid frame" would be.

Digital data (like P25) comes in packets. If your scanner is looking at Close Call (or weather or a priority channel) when the packet starts, then goes back to the control channel, it picks up the latter part of the packet or frame. It's starting the decode in the middle of the frame, or "mid-frame". Since it can't decode that, you hear the frame, not the decoded voice.

 

[pboy]

What exactly is the data burst that is being heard at the start of transmissions?

I don't know about anybody else, but I hear full conversations without anything clipped or missing at the beginning. So I wouldn't think it is a chunk of the coded voice data gone astray.

What precedes the digitized voice on the signal?

 

[Al42]

What exactly is the data burst that is being heard at the start of transmissions?

I don't know about anybody else, but I hear full conversations without anything clipped or missing at the beginning. So I wouldn't think it is a chunk of the coded voice data gone astray.

What precedes the digitized voice on the signal?

The 'kerchunk' of the mic button being pressed. The "dead air" before the person starts talking. The entire transmission isn't a single frame. There may be a few frames transmitted before the first syllable of speech. You may be hearing 1 of those. (You'll probably never hear more than part of 1 frame, but if even one bit of a frame is missing, the frame can't be 'decoded'.)

 

[pboy]

The 'kerchunk' of the mic button being pressed. The "dead air" before the person starts talking. The entire transmission isn't a single frame. There may be a few frames transmitted before the first syllable of speech. You may be hearing 1 of those. (You'll probably never hear more than part of 1 frame, but if even one bit of a frame is missing, the frame can't be 'decoded'.)

It would seem then that the BCD396T is unmuting at a point in the transmission that is non-voice?

 

[Al42]

It would seem then that the BCD396T is unmuting at a point in the transmission that is non-voice?

So it would seem. The only way the scanner knows it's non-voice is to capture a frame. If it gets to the channel in mid-frame it thinks the sound is voice. The only way around this is to not unmute for at least 2 frame times - wait to see if a frame comes along. Then people complain about the decode delay.

(Or it could assume that anything at that audio frequency was a digital frame and stay muted until a different frequency came along - and people would probably complain about the first syllable being chopped off on certain dispatchers.)

 

[jerk]

Where is the great and powerful Paul Opitz?

Does Uniden know about this problem, care about this problem. It just seems to be another "failure" or problem in what is becoming and unending stream of problems.

Will Uniden fix this latest glitch. Inquiring minds want to know. Are they working on it. At least acknowledge that they are hearing about it and "looking" into it.

So far my experience with Uniden has been one of ignore, deny, delay, and not have the information in the computer despite repeated calls... And as far as calling, emailing back, or making contact to my phone calls and email. There has been ZERO response. Yes, they have my cell and home numbers before anyone asks.

AL

 

[918Dave]

That's odd? To date, I can't think of anything in the way of cosmetic or performance issues that haven't been addressed and corrected by Uniden? Given this fact, it's a pretty good bet that Uniden, via Mr. Opitz, is well aware of this latest issue. A little patience shouldn't be too much to ask for.

Dave, kk7re

 

[rhutch]

Al seems to be very short of both patience and tact.

 

[jerk]

Al seems to be very short of both patience and tact.

Maybe so, but all of what I said is the truth. And it’s just your opinion and I think you are wrong. Do you mean diplomacy, or discretion or judgment, or perception? These are all synonyms for tact.

And the whole point to my posting is... Where is Uniden?
Just because someone is on these forums and answers questions but doesn’t acknowledge problems... does not make it any better.

So there is a problem or is there not a problem with the decoded audio.
And is Uniden working on a solution? Simple question and all that is needed is a simple answer. APCO-25 audio is poor on this scanner, and with each firmware upgrade does not seem to be getting any better.

And if Uniden would call me back, which they haven’t, I might not be inclined to post here. But I do post as a warning to others buying that perhaps waiting before buying might be best. I want at least a response from Uniden. Now if I were untactful I would post names and contact numbers of who I spoke with so others could call and harangue them as well. Now there is a solution that might work. But I would use a web site.

Bottom line: I find Uniden's service and responses to issues poor, uneven and in my opinion, unacceptable. You're opinion is different and you are welcome to it.

But denying or ignoring the problem is how class action lawsuits get started, the company always loses and the lawyers always win. Perhaps that's what is needed now.

AL

 

[n3uhh]

Just for the record, since updating to firmware version 1.08.07, my P25 reception has changed. Frequently, during a transmission, the signal will break into static, and become unreadable. I cannot predict when it will happen, but it does frequently. Monitoring the system has become hit and miss, and I can no longer rely on the unit for P25. Luckily, this is not my 'home' system. I will wait, at least for a modest period of time, to see if Uniden provides another update to correct this problem. I really hate to downgrade to an older firmware version unless absolutely necessary.

Otherwise, this radio has become my best and primary receiver, and I really love it!

By the way, the P25 system I listen to is Westmoreland 9-1-1.

 

[jerk]

Just for the record, since updating to firmware version 1.08.07, my P25 reception has changed. Frequently, during a transmission, the signal will break into static, and become unreadable. I cannot predict when it will happen, but it does frequently. Monitoring the system has become hit and miss, and I can no longer rely on the unit for P25. Luckily, this is not my 'home' system. I will wait, at least for a modest period of time, to see if Uniden provides another update to correct this problem. I really hate to downgrade to an older firmware version unless absolutely necessary.

Otherwise, this radio has become my best and primary receiver, and I really love it!

By the way, the P25 system I listen to is Westmoreland 9-1-1.

I just changed back to the old firmware. There was too much “machine gunning” sounds.
Now I just get sssshsss sound before decoding of APCO-25 signals. I thought maybe having other systems turned on that had no signal was affecting this, so I scanned just one, and it’s still there.

But the almost constant machine gunning is gone. On a good note my decode settings did not change like they did when I upgraded. I had them set for optimum, upgraded to v. 8 and they all defaulted back to default. So Uniden, maybe there is a clue to part of the problem. Not that anybody is listening.

I spoke to someone yesterday, high up the “food chain” and he was unaware of the new firmware issue. So either he’s not in the loop or comments here don’t get passed on. I would contact Uniden direct by email, but that doesn’t get results as my last emails were lost or ignored.

AL

 

[walter900]

I have not been around in a week or so....

Whats going on with this issue? I am a UNIDEN man all the way, it kills me to see the pro-96 working much better than my 396........ And for the UNIDEN forum guys (you know who you are) shame on you!!....... stop avoiding this topic like it is the plague!!

I would like to see this issue resolved.... or at the least, acknowledged!! Not disapear into the forums archives!!!

Thank you.

 

[rdale]

Given their past performance with this scanner, I think it's safe to say it is being worked on.

 

[dwlind]

New Firmware

I just checked on Uniden's website and it looks llike new firmware has been posted.