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

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KevinC

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Here you go, post away...
 

QDP2012

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Thanks for downgrading an important issue just like Unidens Android App, starting to wonder who's in who's pocket around here, so glad a member supported site is so trans...ent
You're right....LOL... They swept it under the rug. The equivalent of the Dead Letter Office...Never to be seen again...:roll:...Return to sender....

In my opinion...

The moderator did not downgrade the LSM issue, nor send the issue to the dead-letter office, by creating this thread in the Rant forum.

If the conversations about LSM were heretofore more to the point of actual problem-solving in sufficient detail such that your favorite manufacturer could upgrade their scanners in that manner, then I am guessing (though I cannot prove) that a moderator might have placed such a thread in the general-scanning forum, instead of the rant forum. Most of the comments thus far seem to have been complaints with some general ideas/guesses on solutions, but nothing with enough detail to implement.

The following questions use the word "you" generally toward anyone discussing the LSM issue, and are not aimed individually at any specific person or persons.

Have "you" presented some valid designs to "your" favorite scanner manufacturer in hopes that they will build a scanner with "your" preferred LSM specs? If "you" haven't, then why not? If "you" don't have a working design, why would "you" expect them to have one? Maybe they are working on it, and to keep a competitive edge in the market have chosen to say nothing publicly, just as was done with the DMR and NXDN -related efforts. Griping in any RR forum is just that, griping. A better option would be to bring solutions with enough details that a manufacturer can implement them successfully.

Seriously, if "you" have the technical skill to help solve the LSM problem, please consider contacting your favorite scanner manufacturer and helping them succeed in bringing such a scanner to market at an affordable price-point. Many here would appreciate your efforts. And, I will gladly add my sincere thanks in advance. Thank you!


IMO, the 'Rant' forum should be renamed the 'crybaby' forum... Sheesh.
Sometimes it does seem that way, doesn't it? I wish the moderators had the time to clean-up the DMR/NXDN announcement threads, for both Uniden and Whistler, by moving each LSM dsicussion post to this thread, but there would be hundreds of posts to wade through, and it would be too tedious, likely without a lot of benefit. It would make the DMR/NXDN/New-scanner threads easier to read, though, with regards to their original topics.

The scanner does not decode LSM well. Buy something that does. Vote with your wallet. Do something, but quit whining about it.
On point!

---
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slicerwizard

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Have "you" presented some valid designs to "your" favorite scanner manufacturer in hopes that they will build a scanner with "your" preferred LSM specs? If "you" haven't, then why not? If "you" don't have a working design, why would "you" expect them to have one?
Can't imagine why one would expect a company that's been making radios forever to know how to make a proper receiver. The suggestion that we should be giving them how to tips is quite frankly ridiculous.
 

KevinC

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Can't imagine why one would expect a company that's been making radios forever to know how to make a proper receiver. The suggestion that we should be giving them how to tips is quite frankly ridiculous.

I tend to agree. If Relm figured it out it can't be that difficult. :lol:
 

QDP2012

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Can't imagine why one would expect a company that's been making radios forever to know how to make a proper receiver. The suggestion that we should be giving them how to tips is quite frankly ridiculous.

The suggestion...
...ridiculous though it may be, is nearly as pointless as repeated complaints clogging a thread that is focused on another topic
...was intended to redirect attention toward real problem-solving and away from complaining.
...was one suggestion at how someone might reach out directly to the manufacturer with a positive approach instead of a negative approach.
...could be replaced with another "ridiculous" suggestion, like this one "Instead of complaining to Whistler or Uniden for not (yet) developing an LSM-free scanner at your favored price-point, why not contact the company that has an LSM-free scanner at a higher price-point and complain to them that its price is too high, so that they will lower their price to your desired level?" (And yes, that is a ridiculous suggestion...unless it works.)


Sincerely, an attitude of thankfulness could be a good starting point -- Like placing a phone call, or sending an email, to the manufacturer (example Whistler) and...
...thanking them for picking up the baton after the previous company had faltered/failed, and now bringing a new working product to market;
...thanking them for being a competitor in what was shaping up to be a one-manufacturer market;
...thanking them for their continued development instead of only producing the original GRE products.

Then while thanking them, ask politely about the LSM issue, and what technically is stopping them from overcoming the problem at the price-point you consider affordable. If they can solve the problem but not afford-ably, then that is understandable. If they are having technical difficulties solving the problem, then maybe some expert here can offer some suggestions to aide them along, or could be hired by them as a subject-matter-expert.

Instead of complaining about what hasn't happened, start thanking for the good things that have happened, and if the manufacturer's products are not yet solving a particular problem, either keep encouraging them to solve it instead of complaining that they haven't yet; or go find another manufacturer that has solved the problem.

As someone else suggested, vote with your wallet. Repeated complaints in these forums are likely to lead nowhere productive.

Just one opinion,
 

jcardani

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All,

Max Parke and I have posted on the forums over and over how simple of a change it would be. Max is the expert. His website details how it's done with hardware and the software is clearly documented in OP25. Schematics are included.

I emailed Wendy twice as well as on the forum if LSM was fixed on the new TRX scanners before we assumed it's not supported. No answer was given. I thought it was a valid questions because since they modified the front end they could have replaced the parts.

the only partial response was a post in one of the threads stating that the technical rep. for Whistler said something to the effect LSM support cannot be done done to a scanner. this is totally false. With the right hardware changes and firmware changes it is very doable.

If we continue to put our heads in the sand, the manufacturers will continue to ignore the issue. If volunteers like Max can get it working, it should be easy for a manufacturer to do it. Why should we tell them how do do it when they don't even acknowledge the problem?

LSM support is not just a convenience. And this should not be a rant. If you are not close to a site, scanners are useless. Maybe it will take a certain amount of returns for them to realize is needed.

Whistler blew an opportunity to be the market leader when they did not include LSM support when they modified the radio's front end.
 

RayAir

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I find it easier to custom make my own "scanners" rather than rely on consumer grade scanner manufacturing companies.

Better audio quality. More capabilities. And no issue with LSM.
 

jcardani

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And when the Connect Systems CS7000 is released it will have open source firmware. There's enough talent on these forums to develop a multi-protocol DSD-like firmware that would run on the CS7000 platform.

I find it easier to custom make my own "scanners" rather than rely on consumer grade scanner manufacturing companies.

Better audio quality. More capabilities. And no issue with LSM.
 

RayAir

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And when the Connect Systems CS7000 is released it will have open source firmware. There's enough talent on these forums to develop a multi-protocol DSD-like firmware that would run on the CS7000 platform.


That would be nice. We're kind of missing one key feature that would bring everything together.
 

QDP2012

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All,

Max Parke and I have posted on the forums over and over how simple of a change it would be. Max is the expert. His website details how it's done with hardware and the software is clearly documented in OP25. Schematics are included.

I emailed Wendy twice as well as on the forum if LSM was fixed on the new TRX scanners before we assumed it's not supported. No answer was given. I thought it was a valid questions because since they modified the front end they could have replaced the parts.

Thank you both for directly reaching out to a scanner manufacturer, and offering real solutions to them and to the radio/scanner community at-large.

the only partial response was a post in one of the threads stating that the technical rep. for Whistler said something to the effect LSM support cannot be done done to a scanner. this is totally false. With the right hardware changes and firmware changes it is very doable.

If we continue to put our heads in the sand, the manufacturers will continue to ignore the issue. If volunteers like Max can get it working, it should be easy for a manufacturer to do it. Why should we tell them how do do it when they don't even acknowledge the problem?

LSM support is not just a convenience. And this should not be a rant. If you are not close to a site, scanners are useless. Maybe it will take a certain amount of returns for them to realize is needed.

Whistler blew an opportunity to be the market leader when they did not include LSM support when they modified the radio's front end.

I hope that some day soon all scanner manufacturers will get the LSM problem fixed.

Thanks again for your efforts to help them.
 

KevinC

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I cleaned this up a little. Some posts that are deleted are still quoted by others, so they shouldn't be taken out of context.

We all know none of the current or newly announced Uniden or Whistler scanners handle LSM/CQPSK/HDQPSK properly, so please don't invade those threads with your complaints/concerns.

I still maintain that contacting these companies directly is the best route to take...but that's just me.
 

EricCottrell

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Hello,

It is not as simple a change for scanner manufacturers, as it requires a redesign of their hardware platform and likely a major effort to update their codebase. It was easier for Max because the hardware already supported IQ based demodulation and he only had to write one P25 demodulator.

A new hardware platform would likely have an ADC that can handle a 10.7 MHz IF signal and a DSP chip to do demodulation. New DSP code would have to be written to handle filtering and AM/FM/P25, etc demodulation. If the same main processor is used, then the existing codebase would be updated to load the DSP code, control the DSP, and process the DSP output.

A major question is if the redesign is possible while keeping the scanner at the same price point. Premium scanners tend to cost around $500. The AOR AR-DV1 uses similar DSP based filtering/demodulation and costs more than double $500.

73 Eric
 

dmack550

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Can't imagine why one would expect a company that's been making radios forever to know how to make a proper receiver. The suggestion that we should be giving them how to tips is quite frankly ridiculous.
+1 on that. WE are supposed to be designing Uniden and Whistler scanners??? That's frankly BS.
 

Thunderknight

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I own several scanners (GRE and Uniden). With yagi antennas in my attic, they work reasonably well on the 800 MHz simulcast systems here. Without the yagi, they are almost useless.
Then I got a Unication G4. Wow, a receiver that works on simulcast out the box, stock antenna.

I use several brands of public safety LMR radios too, so I know what the systems should sound like.

Given the ever increasing numbers of P25 simulcast systems, it is amazing to me that the scanner manufacturers are not solving this problem. My guess is either they refuse to acknowledge it, or it is a price point issue.
 

slicerwizard

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Thank you both for directly reaching out to a scanner manufacturer, and offering real solutions to them and to the radio/scanner community at-large.
Paul Opitz participated in at least one thread where the mechanics of LSM reception was discussed, so no need to "reach out" to them.


It is not as simple a change for scanner manufacturers, as it requires a redesign of their hardware platform and likely a major effort to update their codebase. It was easier for Max because the hardware already supported IQ based demodulation and he only had to write one P25 demodulator.

A new hardware platform would likely have an ADC that can handle a 10.7 MHz IF signal and a DSP chip to do demodulation. New DSP code would have to be written to handle filtering and AM/FM/P25, etc demodulation. If the same main processor is used, then the existing codebase would be updated to load the DSP code, control the DSP, and process the DSP output.
Yes, some hardware changes are needed, but they've had years to work on this. Demodulating AM, NFM and WFM, along with extracting symbols from PSK signals is not particularly complicated. Most of the coding that goes into a scanner - keyboard input, display output, PC interface, RR DB, user programmed systems, LTR/EDACS/Moto/P25 protocol handling... - is unchanged.


A major question is if the redesign is possible while keeping the scanner at the same price point. Premium scanners tend to cost around $500. The AOR AR-DV1 uses similar DSP based filtering/demodulation and costs more than double $500.
From what I recall, AORs have always been pricey. It would not be reasonable to attribute the $500+ premium to a DSP based solution.
 

RFI-EMI-GUY

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(snip)

Given the ever increasing numbers of P25 simulcast systems, it is amazing to me that the scanner manufacturers are not solving this problem. My guess is either they refuse to acknowledge it, or it is a price point issue.

Probably a bit of both, Not every scanner owner is going to suffer the "LSM problem" (simulcast delay spread) so they can ignore it. Motorola and Harris had to solve it because they are guaranteeing 95% reliable coverage for the systems they deliver.

That being said, yes an I/Q demodulator is the way to go and the fact that nearly every modern receiver from the SDR dongle to the smartphone now employ this technology at an economical price sort of put Uniden and Whistler up for scrutiny. Lets see what next year brings. Hopefully the next generation receivers will be better.
 

WX4JCW

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Probably a bit of both, Not every scanner owner is going to suffer the "LSM problem" (simulcast delay spread) so they can ignore it. Motorola and Harris had to solve it because they are guaranteeing 95% reliable coverage for the systems they deliver.

That being said, yes an I/Q demodulator is the way to go and the fact that nearly every modern receiver from the SDR dongle to the smartphone now employ this technology at an economical price sort of put Uniden and Whistler up for scrutiny. Lets see what next year brings. Hopefully the next generation receivers will be better.
exactly i can get a DMR with IQ for $25
 

natedawg1604

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Why can't they learn from OP-25, which has been out since, what, 2011 if not earlier? They really should have tested their scanners from day 1, at the design stage, against Motorola/Harris/EF Johnson radios, and/or OP-25, particularly re: audio quality & LSM performance.
 

EricCottrell

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Not quite - in early efforts (2009-2010) the hardware was homebrew - A 455 KHz IF Downconverter for Digital Radio Reception
Hello,

So he has been working on this for 5+ years? Not a short time period in my book. :) He likely leverage some past code in writing a demodulator for OP25.

The next generation scanner could be starting development, but we will not know until it is near to release in 18 to 24 months.

73 Eric
 
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