The official "I want LSM to work properly in my scanner" thread

[iMONITOR]

If the Uniden spokesperson is on here pointing out how expensive designing a scanner that handles simulcast is, rest assured your not going to see a scanner from them that handles it.

He may be pointing out the average scanner consumer might not be willing to pay what it takes.

 

[RFI-EMI-GUY]

He may be pointing out the average scanner consumer might not be willing to pay what it takes.

I think that ship sailed. The BCD536HP was a pricey model advertised to do Phase 2 and simulcast.

Sent from my SM-T350 using Tapatalk

 

[UPMan]

I cannot think of any instance where we have made any advertised claim regarding simulcast. I've never claimed any model has perfect simulcast performance (and would be the source of pretty much any official advertised claim).

 

[iMONITOR]

I cannot think of any instance where we have made any advertised claim regarding simulcast. I've never claimed any model has perfect simulcast performance (and would be the source of pretty much any official advertised claim).

+1 I was about to say the same!

 

[troymail]

However from my experience that is because they simply don't stop on transmissions / produce audio if the digital packets are corrupted badly, where the audio would be a garbled mess. They simply skip the transmission. Whistlers stop on more transmissions, but many of them are garbled and annoying to listen to.

Exactly my experience/opinion also - if it locks onto a (simulcast) control channel at all. For some, this translates into many people saying the 436/536 fully / properly handles simulcast when that is not the case.

I cannot think of any instance where we have made any advertised claim regarding simulcast. I've never claimed any model has perfect simulcast performance (and would be the source of pretty much any official advertised claim).

I think I agree with this as well. I think at best what I recall from a long, long time ago UPMan post was "YMMV". It would certainly be a strong marketing point if Uniden could say they properly handle simulcast. Real or not - I noticed and mentioned a lack of any reference to simulcast on the SDS-100 stuff that was posted a few weeks back as well. If it were to be handled properly, I would expect that to be the first thing on the feature list (in large letters).

 

[RFI-EMI-GUY]

I cannot think of any instance where we have made any advertised claim regarding simulcast. I've never claimed any model has perfect simulcast performance (and would be the source of pretty much any official advertised claim).

I did not use the word "perfect", though the expectation was "properly", and the use of a discriminator has proven not to be proper method for linear simulcast demodulation.

Sent from my SM-T350 using Tapatalk

 

[KA1RBI]

I cannot think of any instance where we have made any advertised claim regarding simulcast.

Uniden advertises "APCO 25 phase II" on this page:
https://www.uniden.com/shop/communication/radio-scanners/homepatrol-series-scanner-with-wi-fi/

The standard P25 specs for P25 phase II specify that a modulation format known as "H-DQPSK" is used on the downlinks. H-DQPSK is (basically) LSM.

How can you advertise "APCO 25 phase II" when your scanners do not implement H-DQPSK?

Max

 

[UPMan]

I and many others listen to P25 Phase II with Uniden (and Whistler) scanners all day long. How could I not advertise APCO P25 Phase II, especially when my competition advertises the same (and performs comparably, although in some environments ours are better, some theirs are better)?

 

[troymail]

Uniden advertises "APCO 25 phase II" on this page:
https://www.uniden.com/shop/communication/radio-scanners/homepatrol-series-scanner-with-wi-fi/

The standard P25 specs for P25 phase II specify that a modulation format known as "H-DQPSK" is used on the downlinks. H-DQPSK is (basically) LSM.

How can you advertise "APCO 25 phase II" when your scanners do not implement H-DQPSK?

Max

You can have Phase 2 without simulcast... so saying a scanner does Phase 2 is not technical incorrect or untrue ... however, one might say it is misleading and/or not being fully transparent ...

 

[KR7CQ]

Exactly my experience/opinion also - if it locks onto a (simulcast) control channel at all. For some, this translates into many people saying the 436/536 fully / properly handles simulcast when that is not the case.

Well said. When people first went out and bought x36 scanners, many came on here and were wowed by the fact that they weren't hearing nearly as much garbled audio, and that is true without a doubt, but a lot of that has to do with the x36 scanners not attempting to stop and produce audio when the packets are corrupted badly. It's not that Uniden said they kicked butt with simulcast, users on RR and in internet reviews said that. To the people now a bit upset that they thought they were buying a scanner that properly handled simulcast, I can see why they feel that way, but it wasn't UPman or Uniden talking about how much better the x36's were with simulcast in fairness.

My mom used to tell me "if you can't say anything nice, don't say anything at all". It appears that the x36 scanners have the philosophy when it comes to producing audio from transmissions received on a simulcast system. If all that's going to come out is 30 seconds of garbled nonsense, they don't produce audio. I'm not sure if that was intentional, but it's the net effect. In the end, I prefer this. I would rather actually hear 10% or 20% of a system's transmissions than to hear a bunch of garbled nonsense that makes me want to turn off that system or the scanner.

 

[troymail]

I would rather actually hear 10% of a system's transmissions that to hear a bunch of garbled nonsense that makes me want to turn off that system or the scanner.

This is somewhat the same argument users have had over the years for staying with analog - "I'd rather hear something and know someone is calling that I might be able to pull useful information out of than not hear anything at all."

There is a similar argument that can be made for (not) suppressing encrypted talkgroups (but that is for another thread).

 

[KA1RBI]

You can have Phase 2 without simulcast...

You might be able to have Phase 2 without simulcast. However you cannot have Phase 2 without H-DQPSK. Any such system would not be standards-compliant. Can you please provide a citation for a system that is running C4FM on the TDMA voice channels? (i.e., it could be running C4FM on the CC but that does not count here). Or, show where in the specs that C4FM on TDMA is allowed?

so saying a scanner does Phase 2 is not technical incorrect or untrue ... however, one might say it is misleading and/or not being fully transparent ...

So, you're saying the scanner manufacturers are allowed to implement some parts of the spec and ignore other parts at their whim, while still advertising compliance?

Max

 

[troymail]

You might be able to have Phase 2 without simulcast. However you cannot have Phase 2 without H-DQPSK. Any such system would not be standards-compliant. Can you please provide a citation for a system that is running C4FM on the TDMA voice channels? (i.e., it could be running C4FM on the CC but that does not count here). Or, show where in the specs that C4FM on TDMA is allowed?

All I am saying is that I have monitored systems (or at least sites on systems) that are Phase 2 and not simulcast.

Also - you can monitor Phase 2 - even simulcast - on a scanner - just not (always) very well.

So, you're saying the scanner manufacturers are allowed to implement some parts of the spec and ignore other parts at their whim, while still advertising compliance?

Max

A company can produce anything it wants - it is up to the consumer if they buy it or not.

Having said that - I learned from my x36 "experience" that I won't be pre-paying for or even try to be first in line for any new Uniden scanner going forward. In fact, that experience even affected my decision to purchase other radios since then as well. I was seriously "on the fence" about the Unication G4 before making that purchase (more due to the limitations than the features). I relied heavily on an extremely reliable local source who was willing to spend the money to determine if it solved the simulcast issues I was wanting to overcome before laying out almost $700 for it.

 

[KR7CQ]

This all brings me back to when simulcast first hit Phoenix....like 12 or 13 years ago I believe....I was up on a roof with a yagi mounted to my main mast connected to a PSR-500 I believe, moving it into various positions, trying to get it pointed just right, so that I could actually hear what people were saying lol.

 

[KA1RBI]

How could I not advertise APCO P25 Phase II, especially when my competition advertises the same (and performs comparably...

haha, yep, two wrongs make it right.

73

Max

 

[KR7CQ]

This is somewhat the same argument users have had over the years for staying with analog - "I'd rather hear something and know someone is calling that I might be able to pull useful information out of than not hear anything at all."

There is a similar argument that can be made for (not) suppressing encrypted talkgroups (but that is for another thread).

Not me...I don't want to hear a bunch of nonsense....it's annoying, but I'm sure opinions vary. As far as listening to encryption and planning to get useful information out of what you hear, good luck...you might make out one word here or there. I always wondered why when Motorola developed the new encryption methods they didn't make it sound like the old DVP encryption used in the 90s...just a tone, and then white noise.

 

[troymail]

Not me...I don't want to hear a bunch of nonsense....it's annoying, but I'm sure opinions vary. As far as listening to encryption and planning to get useful information out of what you hear, good luck...you might make out one word here or there. I always wondered why when Motorola developed the new encryption methods they didn't make it sound like the old DVP encryption used in the 90s...just a tone, and then white noise.

As far as garbling - sometimes you can make sense of the voice even though it is not 100% clear - that can be better than not hearing anything at all. However, as you said, this is something that should be optional - not decided for you - particularly if it leads you the user to believe the voice you do actually hear makes the radio's performance "perfect" (because it is hiding things).

As for encryption - again - needs to be an option. This isn't so much to try to "hear" the encrypted voice (you won't) - it's more about following activity and other related info. For example:

• a user on a clear talkgroup says "switch over..." - you can track that relationship (using voice, time, and radio IDs, etc.) and use it to help identify talkgroups as "law", etc. and/or submit them for the database
  
  
• users learning the hard way (after the fact) that they can't use their new radio because the talkgroups they want to hear are encrypted (on Unidens, it even makes people think their radio isn't working) - some of this is because of the difficulty gathering sufficient information to allow submitting it to the database (which "feeds" this part of the problem).

Ok - sorry I've drifted us a bit into a different (but similar) discussion...

 

[KR7CQ]

As far as garbling - sometimes you can make sense of the voice even though it is not 100% clear - that can be better than not hearing anything at all. However, as you said, this is something that should be optional - not decided for you - particularly if it leads you the user to believe the voice you do actually hear makes the radio's performance "perfect" (because it is hiding things).

As for encryption - again - needs to be an option. This isn't so much to try to "hear" the encrypted voice (you won't) - it's more about following activity and other related info. For example:

• a user on a clear talkgroup says "switch over..." - you can track that relationship (using voice, time, and radio IDs, etc.) and use it to help identify talkgroups as "law", etc. and/or submit them for the database
  
  
• users learning the hard way (after the fact) that they can't use their new radio because the talkgroups they want to hear are encrypted (on Unidens, it even makes people think their radio isn't working) - some of this is because of the difficulty gathering sufficient information to allow submitting it to the database (which "feeds" this part of the problem).

Ok - sorry I've drifted us a bit into a different (but similar) discussion...

Fair points. I know some would rather try to make out what they can in a garbled simulcast transmission, and / or to verify TG activity despite encryption...I do have Whistlers for that.

A "play audio with encryption" setting might be a valuable thing to many.

 

[UPMan]

I think this sums up the prevailing attitude regarding being able to make a 25 - 1300 MHz scanner that works well on all bands and that uses the kind of receiver circuit y'all are talking about and can be afforded by enough people to make it worthwhile:

https://www.youtube.com/watch?v=7Sor0LXiSZg&feature=youtu.be&t=12

 

[captainmax1]

LOL. DOH!