BCD536HP Discussion Thread

[SCOTTER]

I understand what your saying DPD1 all I wanted to know was do the new scanners had the same XT digital auto decode not how it does on all systems.The reason being it was the # 1 gripe on the fourms the past 4 years or so. So if I sell my XT and get one I want it to work better than the XT thats all I hope it does I love Uniden I have scanners phones ect made by them and I am very brand loyal.

 

[BenScan]

I should have been more specific when I said "hardware". I'm sure there is some hardware difference, but more specifically the receiver/radio portion is what I was getting at. If the receiver hardware is the problem, then hopefully it was be replaced. If the receiver can be corrected with a firmware update, and it's the same hardware in the HP-1 and XTs, then I expect Uniden to make those right. My understanding of the problem is that if the receiver cannot make sense from several signals from multiple paths, it's not going to work.

I want the scanners to be a success. I look forward to trying them out, and Uniden providing a fix for the HP-1s and XTs I've already invested in.

I don't recall if it was merely hinted or if it was stated outright that the new scanners use different hardware. Even in the promo video, it was hinted that Uniden could have merely put a faster processor in the 396 and called it a new model. That implies that the new units have faster processors.

Joe M.

 

[kaiserfan]

In regards to P25 simulcast issues, if they didn't change hardware, compared to the HP-1 and XTs, and the reception is better, I wonder when we'll see some firmware updates for those. I have 1 HP-1 and 7 XTs, that essentially do not work now for one of the most important systems in my area. If the reception is not better, then I'm not likely to buy any more until Uniden really addresses the P25 simulcast problems.

Agree if the 436 and 536 are better at handling simulcast systems why don't they update the firmware for the HP1 to fix this issue answer that please UPMAN

 

[Jay911]

Agree if the 436 and 536 are better at handling simulcast systems why don't they update the firmware for the HP1 to fix this issue answer that please UPMAN

Because, as I said before, a firmware update to change hardware inside a radio is impossible. Paul has stated time and time again that earlier radios like the x96XT and the HP1 do not have the hardware necessary to handle this. You may as well ask for firmware updates to change the antenna connector from SMA to BNC. It ain't gonna happen.

 

[CoryD81]

I don't recall if it was merely hinted or if it was stated outright that the new scanners use different hardware. Even in the promo video, it was hinted that Uniden could have merely put a faster processor in the 396 and called it a new model. That implies that the new units have faster processors.

Joe M.

It was indeed stated that the new line uses new processors/hardware to handle the P-25 Phase II and X-2 TDMA capabilities. They said they 'could've fit this new processor into the 396 package and called it a day, but why stop there?' So they redesigned the handheld unit altogether, while the 536 uses the same 996 chassis, similarities end just about there as what's inside is much different (uSD card capable, rear USB port/wi-fi dongle, new front panel/display, etc). As far as those asking about Simulcast issues with previous models there are many variables as to the source of that problem, many are getting LSD due to being just about equidistant from Simulcast towers and having a problem with which signal to trunktrack and getting distortion that way, but living in the Twin Cities Metro area in a statewide P-25 Phase I system with many of the Metro Sites being Simulcast I have dealt with this myself on the 996XT....but not for very long. I've found that unless you are almost exactly the same distance between equally powered Simulcast towers you can change the unit's P-25 settings to fine tune it to your area and find thresholds that single out the stronger of the 2 or more signals your scanner is battling to decode. I live close (not exactly) to halfway between two of the multiple Simulcast Sites in my county and if the P-25 settings are left untouched or set wrong it will distort, but having changed those settings I have resolved 95%+ of that issue that way alone. The type and placement of the receiving antenna can make up another 4.9% of the issue that remains by either going directional or placing it in such a manner to make a wide-band or 800mhz omnidirectional antenna even slightly more favorable towards a general direction or creating a small (doesn't have to be much) blind spot in it's directional receive area which in normal, factory designed settings is 360 degrees, but placement off center on a vehicle or towards one side or corner of a house will change this slightly to create areas with line of sight and areas with lower gain or a drop in signal making your scanner not receive more than one control channel data signal from more than one source with the exact same strength. If you are close to these Sites you can attenuate that Site to make it easier to pick out the stronger signal. I can't prove this on Phase II since MN doesn't have any around here yet or plan to in the near future (although I am prepared if we suddenly aren't as broke as we seem to be and they decide to dump a few hundred million on an upgrade we don't need....lol), but I run a Public Safety feed from an inner-ring Minneapolis suburban county that is Simulcast with several towers/sites, 3 of them being close to the same distance from me, 2 are VERY close to being exactly the same distance (less than a half mile (.32 to be exact) difference in distance) from my feed receive location but I was able to remove almost all of the distortion from my audio and what little I do get usually is actually a poor input signal from a portable and dispatch even can't hear it and says his/her signal is unintelligible and requests a friendly '10-9?' so obviously there isn't anything I can do about that. But, if anyone wants to hear a P-25 Phase I Simulcast system that used to have distortion problems with the same exact setup in the same location but has been resolved using the above methods it can be heard on it's BC feed here:
Anoka County Public Safety

 

[kaiserfan]

Because, as I said before, a firmware update to change hardware inside a radio is impossible. Paul has stated time and time again that earlier radios like the x96XT and the HP1 do not have the hardware necessary to handle this. You may as well ask for firmware updates to change the antenna connector from SMA to BNC. It ain't gonna happen.

so i bought a scanner that 70 per cent of the time is useless and annoying

 

[CoryD81]

Because, as I said before, a firmware update to change hardware inside a radio is impossible. Paul has stated time and time again that earlier radios like the x96XT and the HP1 do not have the hardware necessary to handle this. You may as well ask for firmware updates to change the antenna connector from SMA to BNC. It ain't gonna happen.

Well, Jay beat me to it and said exactly what I was going to, firmware updates will only change or modify things that can be changed or make it able to do things the physical hardware was already able to do but the FW coding wasn't created or figured out to allow it in previous versions of the FW or the original model when it was unveiled. Take for example the Radio ID feature of the x96XT series, the 1.06.00 series of firmware added that feature to the scanner, but the display itself, the information it decoded from MOT/P-25 systems, etc was already there and in place to allow this update to be possible. The new line of scanners has a new processor, that much we know for sure, but with that new processor one could say with a pretty high degree of confidence that it would take more than just the processor to add TDMA capability to a scanner and there are other physical changes in the circuitry and signal processing to break that down to audible voice transmissions we hear out of the speaker, so I would doubt they would develop all of that for TDMA use and not somehow update or integrate more advanced, higher quality overall signal processing for FDMA (Phase I) or other more basic modes analog or digital. I could be wrong, but with integrated DSP's it would seem almost harder or more expensive to try using to x96XT series' Phase I processing components and also adding a Phase II/TDMA capable processor and other circuitry to handle that format, seems redundant and I would think that there would be integration of many of those components and thereby making most all of the digital decoding/processing new compared to x96 or other digital models. Since the processor is the heart of the scanner and was the component mentioned in the release video about the possibility of fitting this new processor into the older 396 package, one without any advanced digital electronics/audio processing knowledge might be able to see that this new processor is doing the brunt of the digital-formatted audio's work as far as taking FDMA, TDMA, X-2 TDMA, etc signals and making them able to be trunktracked an audible....so I wouldn't worry about lack of improvements in that aspect, obviously they made a huge change to it's core component to make Phase II/TDMA a new feature for Uniden. I'm not an electrical engineer, so if I got a few or many terms or specifics wrong I apologize, but I think the general idea is correct.....if not I'm open to being corrected any day of the week! No better way to learn than finding out you're wrong....lol

 

[KE4ZNR]

so i bought a scanner that 70 per cent of the time is useless and annoying

This is where I say that research before any purchase is a good idea.
I understand that you are not happy with the radio you purchased but this
thread is not for complaining about past purchases.
This thread is for discussing the upcoming BCD536HP scanner.
Let's please get this thread back on topic and any further off topic posts
will be deleted.
Thanks for understanding and Happy Monitoring
Marshall KE4ZNR

 

[redburgundy]

I've found that unless you are almost exactly the same distance between equally powered Simulcast towers you can change the unit's P-25 settings to fine tune it to your area and find thresholds that single out the stronger of the 2 or more signals your scanner is battling to decode.

Can you point us to more information or a thread on what settings to change?

 

[CoryD81]

so i bought a scanner that 70 per cent of the time is useless and annoying

That depends on why you consider it useless and annoying, if it's an audio format issue like a proprietary format or Phase II/TDMA that your scanner can't decode, then I guess that's one way to put it. But-if you are having problems with P-25 Phase I or a system it's capable of receiving than I would bet there are a few things you can do to drastically improve your reception or audio quality. It comes down to what the core problem is that is causing your scanner to behave that way; Is it Simulcast distortion? Improper P-25 settings, like threshold, etc where it tries to listen to Sites that have a very high error rate when they should be dropped and continue to scan for ones with better quality can be a cause for some of those types of issues for multiple site systems. I'm assuming you have a good or very good signal strength to work with, otherwise digital audio is one of the worst ways to try listening to a weak signal. It can be compared to how Li-ion batteries work: they have a full voltage for the first 80% or so of it's charge then if you looked on a graph after it gets to a certain point it just plummets to nothing in a very short period of time; The same is true with digital audio, as long as you have a full or very good signal things should work just great, but once it drops below a certain value or the error rate gets too high, the end-user's audio quality (what you actually hear) drops off and sounds almost like it's encrypted (if you've ever heard that on P-25) and you won't be able to make any sense out of it unlike a weak VHF or UHF analog signal that you can still hear, just the voice gets a little quieter and the static starts to get louder (or appear in the first place) but is intelligible nevertheless. If you have good or full signals maxing out the strength meter on the control channel(s) and you suspect (or know) it's a simulcast issue, then there are things you can do to improve it tremendously or even get rid of the problem. Without knowing what system(s) you're trying to monitor I can't say exactly what to recommend, but if it's Simulcast and you can sacrifice receiving from a particular direction and point a directional antenna towards a SIte/tower that you know transmits the stuff you want to hear than that will certainly make a major difference, otherwise antenna or scanner location depending on your setup, can make a lot more difference that most people would believe, I once had my 996XT in a spot with the stock antenna indoors where it would receive fine--unless my hand was just near, or especially touching the buttons or any part of the scanner at all, then it would distort terribly and act erratically. Turned out the location I had it was near some (or maybe even a few) RF interference and/or electrical interference that made it particularly sensitive to any changes within its proximity....moved it about 5' over to a different spot in the office and went to an external antenna, even put a clamp-on ferrite choke on the antenna's feedline into the scanner in case there was something in my area or home causing it, but the new location and external antenna solved all of that and the ferrite choke was not needed at all, for all I know the stock telescoping antenna had a defective BNC connector or something else wrong with it or wi-fi around here was somehow affecting it in that spot. Just a few things to consider before giving up on it....

PS-If you do give up on it, PM me---I will buy it from you at a fair price (unless its actually defective, then NVM :-/ )

 

[CoryD81]

Can you point us to more information or a thread on what settings to change?

This is copy/pasted from an email of mine after the last firmware was released and this 'hidden menu option' became available. I cannot attest to the actual values that are mentioned in here, IIRC the factory settings are 8 for the threshold limit (which I believe I changed by only one number, but don't remember which direction...sorry :-/ ) and 50 for the P25 adjust mode, although this particular instruction says to leave or reset it to 50, in the forum link below you will find people have had much improvement and success by changing that to a higher level, especially on weaker signals.....I can't confirm or recommend that changing the threshold value to 11 is prudent for you or your system or that it is "optimal for most P-25 systems" (it should be noted that the who I was talking to about this a while back found that the setting of 11 was optimal for HIM in HIS location out by the east coast and for a few other systems he monitored while traveling including many in Australia) but it might be worth playing around with, you can always change it back to the default settings if you don't see improvement, but odds are if you have a signal strong enough to decode and are having issues, playing with these settings may tailor the scanner to your particular situation and make it sound exponentially better. (EDIT: This will only work with the x96XT series (not sure about the T) with the latest 1.07.03 firmware)
(Additional EDIT: For Simulcast system issues; If you already have strong/full signal strength on the scanner's meter, then it might not be a good idea to try upgrading your antenna or putting it on the roof or to some effect that it brings in more signals from the same Simulcast Site which could make the problem worse by having even more sources of control channel data to deal with and cause distortion. If you're not trying to pick up distant Sites and your local Simulcast Site is the problem then either going directional towards a particular tower, attenuating the Site, or using an antenna with less gain may help you....some people have even reported using a paper clip as an antenna and that solved their Simulcast distortion issues making the scanner only hear the strongest or closest tower instead of multiple or several. Of course every situation is different and YMMV but I don't want to wander too far off topic as we are no longer talking about the 536 and I just saw the post from the Forum Mod, so I'll leave this aspect of the discussion at that and anyone with further questions or wants to talk discuss the x96 series or any of their Simulcast issues either PM me or we can take it to the appropriate forum.)

Copied Text Begins Here:

This update improves decoding on many P25 systems.
For cases where the default settings are not optimal, the update also adds a setting that allows you to adjust the auto decode threshold limit.

BCD 996 XT

To adjust the auto decode threshold limit, start with the scanner powered off. Then, follow these steps:
1.While holding down the HOLD button, power on the scanner.
2.Access the hidden P25 Adjust Mode menu by MENU --> Settings --> P25 Adjust Mode.
3.Set the mode to 11, which is the optimal setting for most P25 systems. Some systems are reported to decode better at a setting of 8.
4.If you have previously adjusted the P25 Adjust Level, reset it to a value of 50 by MENU --> Settings --> P25 Adjust Level.


BCD 396XT

To adjust the auto decode threshold limit, start with the scanner powered off. Then, follow these steps:
1.While holding down the HOLD button, power on the scanner.
2.Access the hidden P25 Adjust Mode menu by MENU --> Settings --> P25 Adjust Mode.
3.Set the mode to 11, which is the optimal setting for most P25 systems. Some systems are reported to decode better at a setting of 8.
4.If you have previously adjusted the P25 Adjust Level, reset it to a value of 50 by MENU --> Settings --> P25 Adjust Level.

End of Copied Text.


Here is a forum that discusses the settings for P25 audio as well, although I'm sure they're are many more on here:

http://forums.radioreference.com/uniden-scanners/269571-best-setting-p25-audio-bcd996xt.html

 

[UPMan]

The new models use a different processor than our XT series and also the P25 voice decoding codebase is new (to support the X2-TDMA and Phase 2 data rates). I have no idea how much of the Phase 1 codec code is shared, as all we receive is a "black box" software module from DVSI and have no visibility to the code itself.

 

[derevs]

While I am no expert on the new communications standards in use, I want to throw in my 2 cents worth.

All of the complaints I am reading about simulcast problems with my limited knowledge I would say that one should lockout/avoid certain sites that are simulcasting in your vicinity. This would relief the simulcast problem as you would only be picking up 1 site.

I am sure that the "professional" radios have data systems built in that would choose the closest site to the mobile radio. This type of technology would not be possible in a scanner as data codes would be needed to talk to the base station.

 

[UPMan]

That isn't possible. Simulcast means that multiple towers are all operating on the same frequencies...to the scanner, they look like one site. You cannot just lock out one of the simulcast towers.

 

[KA1RBI]

Simulcast distortion

The simulcast distortion problem is old news and was fixed long ago in the OP25 project.

The root cause of the problem in all current generation scanners is that the DSP is located after the FM demod. When a P25 signal with additive simulcast distortion is applied to an FM demodulator (discriminator / PLL etc). the resulting "C4FM" signal cannot be properly decoded, and the correct signal cannot be recovered. The solution is to demodulate the signal as (D)QPSK. This requires access to a copy of the signal at IF, prior to the FM demodulation function.

The relevant technical question for UPMan is very simple.

Does the BCD536 utilize IF DSP, or, as in all current scanners is the DSP located after the discriminator?

Amateur manufacturers have featured IF DSP for years...

73

Max

 

[BenScan]

"Simulcast" means the same frequencies are used at more than one physical site. I wish it was that simple.

While I am no expert on the new communications standards in use, I want to throw in my 2 cents worth.

All of the complaints I am reading about simulcast problems with my limited knowledge I would say that one should lockout/avoid certain sites that are simulcasting in your vicinity. This would relief the simulcast problem as you would only be picking up 1 site.

I am sure that the "professional" radios have data systems built in that would choose the closest site to the mobile radio. This type of technology would not be possible in a scanner as data codes would be needed to talk to the base station.

 

[SCOTTER]

Thank you UPMan for your answer in post # 692 thats all I wanted to know have a great weekend.

 

[KCoax]

Another issue is multiple systems that use same frequencies with different NAC. In conventional mode this is not a problem. The scanner has an option to load the NAC. Programming trunk systems in the market available scanner do not allow a system ID setting. In Kansas the KSICS has several towers that share frequencies with MARRS. The sites that share frequencies have to be locked out or TGID will show up in search mode on other systems. I suppose this isn't a common problem and one a GPS could solve if one were traveling. Not so good for trop ducting on near busy systems.

 

[Jay911]

Another issue is multiple systems that use same frequencies with different NAC. In conventional mode this is not a problem. The scanner has an option to load the NAC. Programming trunk systems in the market available scanner do not allow a system ID setting. In Kansas the KSICS has several towers that share frequencies with MARRS. The sites that share frequencies have to be locked out or TGID will show up in search mode on other systems. I suppose this isn't a common problem and one a GPS could solve if one were traveling. Not so good for trop ducting on near busy systems.

This is a problem not only with instances like yours, but situations where a large trunk system repeats frequencies in its own system as well. Your situation is much more frustrating, though, IMO. For me, all I have to deal with is wondering why I'm picking up the tower that's three towns away on the other side of my city (when in fact I'm picking up the tower nearby me, but the scanner recognized the other site because of the common frequencies).

It'd be nice if the scanners would make use of the site identifying info such as RFSS, Site, NAC, heck, even the WACN and SysID.

 

[pepsima1]

I have the ability to either use C4FM or CQPSK. Problem solved. I never got frustrated or pulled my hair out trying to tell scanner makers like Uniden to fix my Simulcast LSM issue. I hear all of this wasted talk and energy going back and forth about these issues and the horse has been beaten to death over and over again. Let nature take its course then make a solid decision to ease your stress over this issue.

Sometimes you have to take the bull by the horns and fix the problem yourself.