BCD536HP Discussion Thread

[KA1RBI]

Max: We don't discuss our proprietary designs.

haha - in contrast, the OP25 research project recently made a major update to trunking support. We publish all of our advancements in source code form so that any and all may learn from our research. This is the current list of supported features, as published on the wiki page SignalScopePage

" New in late 2013, trunk following for multiple trunked P25 systems was added, supporting the following feature set:

* Any number of separate trunked systems may be scanned
* P25 Phase I (IMBE) voice channel decoding and audio output
* Supports LSM/CQPSK systems that require CQPSK (not C4FM) demodulation in addition to C4FM systems
* Since CQPSK demodulation is used, LSM simulcast distortion is suppressed (contrary to all current scanners)
* In this release, systems and voice channels are scanned sequentially (like trunk tracking scanners)
* Alpha tagging for talkgroup ID's
* Per-system whitelist (closed group) support: only those talkgroups in the list are scanned
* Per-system blacklist support: all talkgroups are scanned, except those listed
* Configuration files are TSV (tab-separated); may be edited using spreadsheet software such as Libre office
* Talkgroup ID hold: momentary delay after each voice transmission to allow following conversations
* Manual talkgroup ID hold: click to pause, remains on current talkgroup until resumed
* Manual lockout: click to lock out current talkgroup
* All of the signal scope functions (see above) are live and may be selected in real time
* Traffic history including list of active voice channels, key trunk control channel data, etc.
* Hardware support provided by gr-osmosdr ​GrOsmoSDR including usrp/uhd, hackrf, and (in theory) RTL DVB-T based sticks etc. "


-- none of the above is "proprietary". In fact the OP25 project is founded on the use of the GNU General Public License (GPL), which outlines the four fundamental freedoms
"
* The freedom to run the program, for any purpose (freedom 0).
* The freedom to study how the program works, and change it so it does your computing as you wish (freedom 1). Access to the source code is a precondition for this.
* The freedom to redistribute copies so you can help your neighbor (freedom 2).
* The freedom to distribute copies of your modified versions to others (freedom 3). By doing this you can give the whole community a chance to benefit from your changes. Access to the source code is a precondition for this."

Best Regards,

Max

 

[03msc]

haha - in contrast, the OP25 research project recently made a major update to trunking support. We publish all of our advancements in source code form so that any and all may learn from our research. This is the current list of supported features, as published on the wiki page SignalScopePage

" New in late 2013, trunk following for multiple trunked P25 systems was added, supporting the following feature set:

* Any number of separate trunked systems may be scanned
* P25 Phase I (IMBE) voice channel decoding and audio output
* Supports LSM/CQPSK systems that require CQPSK (not C4FM) demodulation in addition to C4FM systems
* Since CQPSK demodulation is used, LSM simulcast distortion is suppressed (contrary to all current scanners)
* In this release, systems and voice channels are scanned sequentially (like trunk tracking scanners)
* Alpha tagging for talkgroup ID's
* Per-system whitelist (closed group) support: only those talkgroups in the list are scanned
* Per-system blacklist support: all talkgroups are scanned, except those listed
* Configuration files are TSV (tab-separated); may be edited using spreadsheet software such as Libre office
* Talkgroup ID hold: momentary delay after each voice transmission to allow following conversations
* Manual talkgroup ID hold: click to pause, remains on current talkgroup until resumed
* Manual lockout: click to lock out current talkgroup
* All of the signal scope functions (see above) are live and may be selected in real time
* Traffic history including list of active voice channels, key trunk control channel data, etc.
* Hardware support provided by gr-osmosdr ​GrOsmoSDR including usrp/uhd, hackrf, and (in theory) RTL DVB-T based sticks etc. "


-- none of the above is "proprietary". In fact the OP25 project is founded on the use of the GNU General Public License (GPL), which outlines the four fundamental freedoms
"
* The freedom to run the program, for any purpose (freedom 0).
* The freedom to study how the program works, and change it so it does your computing as you wish (freedom 1). Access to the source code is a precondition for this.
* The freedom to redistribute copies so you can help your neighbor (freedom 2).
* The freedom to distribute copies of your modified versions to others (freedom 3). By doing this you can give the whole community a chance to benefit from your changes. Access to the source code is a precondition for this."

Best Regards,

Max

Unless I'm reading it wrong, it looks like you are talking about 'software' stuff here and earlier you were asking about hardware schematics specifics. Big difference. And Uniden (or any company) would be unwise to publish their schematics and/or other proprietary details...

 

[UPMan]

On the software side, we legally license the AMBE/IMBE protocols from DVSI and are not allowed to decompile or redistribute their intellectual property.

 

[KA1RBI]

Unless I'm reading it wrong, it looks like you are talking about 'software' stuff here and earlier you were asking about hardware schematics specifics. Big difference. And Uniden (or any company) would be unwise to publish their schematics and/or other proprietary details...

1) It is just as possible to peform the FM demodulation function in software as it is in hardware.

2) In DSP, it is often exceedingly difficult to specify where hardware ends and software begins.

3) Just did a random google search "kenwood if dsp" and am now looking at an ad for the TS-590S. One of the top selling features listed is

32-bit floating point DSP

-- if scanners have this feature, why wouldn't they advertise it?

4) Any software is only as good as the hardware that it runs on. If the hardware is causing signal corruption, no amount of software coding can clean up the problem.

5) The reason for asking about the hardware (in block diagram form) was an attempt to establish the constraint conditions under which the x36 DSP must operate.

6) The primary reason for my earlier posting in response to UpMan's non-answer was to highlight how much the comment about "proprietary designs" struck me as dinosaur thinking from the previous century.

Best

Max

 

[KA1RBI]

On the software side, we legally license the AMBE/IMBE protocols from DVSI and are not allowed to decompile or redistribute their intellectual property.

Yep. However, the function of demodulating the signal is in a totally separate, unrelated functional processing block from the xMBE codec...

Max

 

[MattSR]

With respect UPman,

The RF demodulation stage has nothing at all to do with MBE licensing whatsoever. Its like saying "Oh, we can't discuss the antenna connector or power supply because we properly license the digital voice codec MBE and can't divulge its' details". The details are specified in the DVSI patent documents and are freely available anyway.... It feels as if you are attempting to avoid the question.

It's a bit of a stretch to say that the receiver designs are proprietary - it's either a simple FM receiver (that was patented in 1914 by the way), or baseband (Zero-IF) architecture at the end of the day, and thats all Max is asking. A better approach would be to openly discuss the architecture because it's as a selling point... not some kind of black magic.. (take ICOM's IF-DSP for example)

Sure, the MBE codecs are proprietary but thats got nothing at all to do with what we are talking about. The P25 Phase 1 simulcast reception problem lies in the receiver design not the MBE codec.

As far as the 436/536 goes, the issue has either been identified and fixed, by re-engineering the demod section, or it hasn't. If it has, then its a selling point, if it hasn't changed, then just say so...

With respect UPman, It appears from the way you are diverting these questions, that these new scanners have not changed at all in this area, and will still suffer the same issues with P25 Phase 1 LSM as does every other scanner out there.

It's somewhat amusing that the free and open OP25 project has solved the LSM problem, documented it and made it publicly available - and it has been developed by engineers working in their spare time, for no reward at all. Oh, and did I mention it receives LSM simulcast perfectly...?

Regards,
Matt

 

[MattSR]

Message removed - pending verification of some info.

 

[UPMan]

As noted, my last response was specifically referencing the software, not the hardware design.

 

[MattSR]

Yes, I understand that point, however we are asking you to address the question regarding the receiver design.

 

[UPMan]

I see.

 

[LiquidPandora]

Yes, I understand that point, however we are asking you to address the question regarding the receiver design.

Get a job at Uniden.. then ask

 

[MattSR]

I can only assume you are not replying to my question in order to comply with your code of conduct rules #1, #2 (subsection 3) and #6?

That's fair enough, but really - theres nothing proprietary about an FM receiver or a quadrature receiver. answering one way or the other will give us a realistic indication as to the simulcast performance of these receivers.

Please keep in mind that as part of the OP25 project, we have implemented a proper LSM/Simulcast/CQPSK receiver that works 100% and we do understand how these things work.

In any case, time will tell all

Regards,
Matt

 

[MattSR]

Get a job at Uniden.. then ask

Why would I work there? I'm already a part of a project thats built a full P25 transmitter and receiver.

A radio and a screwdriver is all I need to answer the question.

 

[UPMan]

Director of Marketing and Product Management at Uniden in Dallas/Fort Worth Area - Job | LinkedIn

And yes, thanks for your understanding.

 

[wise871]

Tonight I decided to put together a quick basic operations video. It's by no means up to par with UPMans videos but it gives you an idea from a regular users who is proficient with the XT and HP-1 scanners. Hope it gives some of you a better idea of the operations. I'm sure I made mistakes in the terms and operations, LOL. I'm learning something new each day. I will make another one this weekend.

Video failed to upload. Trying again.

 

[LiquidPandora]

Director of Marketing and Product Management at Uniden in Dallas/Fort Worth Area - Job | LinkedIn

And yes, thanks for your understanding.

NICE...

 

[LiquidPandora]

Tonight I decided to put together a quick basic operations video. It's by no means up to par with UPMans videos but it gives you an idea from a regular users who is proficient with the XT and HP-1 scanners. Hope it gives some of you a better idea of the operations. I'm sure I made mistakes in the terms and operations, LOL. I am learning something new each day. I will make another one this weekend.
BCD536HP Basic Operation - YouTube

Thank you for taking the time..... When it's done Processing I will take a gander

 

[wise871]

Video failed to upload, I'll try again.

 

[mancow]

Why would I work there? I'm already a part of a project thats built a full. ll P25 transmitter and receiver.

A radio and a screwdriver is all I need to answer the question.

I wish I could get my hands on one to open it up and see. A quick picture would tell the story. Then again I will probably buy one regardless. They are just too sexy to resist.

 

[forums manager]

Everyone, we're getting reports almost every day about OT related posts in this thread. Being we're at 1,300+ posts this thread is beyond casual reading. As we've requested before please try to provide useful posts with questions and answers that will help others. If Paul does not answer a question or does not provide the answer you want, then please move on and leave it at that. Thank you for your cooperation.