Could Uniden Ever Design A Scanner To Properly Decode Trunked Simulcast Systems?
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Yes, SPS can mean samples per second. However (and I can paste links, too 
).
SPS - Symbols Per Second (digital communications) | AcronymFinder
What does SPS stand for?
SPS stands for Symbols Per Second (digital communications)
SPS - Symbols per second
Million Symbols per Second - How is Million Symbols per Second abbreviated?
Sps | Define Sps at Dictionary.com
Taken in context, it is this meaning of SPS that is used when discussing the demodulated digital communications.
).SPS - Symbols Per Second (digital communications) | AcronymFinder
What does SPS stand for?
SPS stands for Symbols Per Second (digital communications)
SPS - Symbols per second
Million Symbols per Second - How is Million Symbols per Second abbreviated?
Sps | Define Sps at Dictionary.com
Taken in context, it is this meaning of SPS that is used when discussing the demodulated digital communications.
Taken out of context, it is.
Now, put BACK in context, with respect to the dongles we are talking about, LSM requires the power of a PC to process.
The dongles do not process LSM internally.
True, it need not be a PC, but again that is splitting hairs which is the only way that argument can be won. Note that I also said the POWER of a PC. That means the CPU (which, ironically, is what you said).
But, your quote proves what I was saying, so thank you for the support.
br0adband
Member
but they could if they had the specific circuitry/chip designed to do that task which is what Max is trying to point out (I believe) just to finish that line of thinking to its proper conclusion.
And I also believe what Max has been saying all along is that modern scanners are capable of doing this task of handling LSM properly with the addition of that circuitry/chip and it wouldn't increase the cost to any given degree.
To make a modern scanner fully capable of proper handling of LSM is a rather trivial task considering, at least that's my take on the situation given the information Max and slicerwizard and jcardani have provided. I'm not any kind of electrical/electronics/communications engineer but even I can see this is a possibility that could be implemented rather simply.
I have to ask: Are you being obtuse on purpose?
KA1RBI
Member
yep - that's the key. The "SPS" is ambiguous without proper context. That applies as well to posts right in this thread, as slicerwizard was wholly correct to point out.
It is interesting to look at the actual numerical values at issue here (P25P1 LSM): a symbol rate of 4,800 (per second) with an occupied spectral bandwidth of 12.5 KHz. According to Nyquist the absolute minimum sampling rate we can use while retaining all of the information in the original would be 25 KHz*. The OP25 project has found the standard sound card sampling rate of 96K samples/sec. to work well with both C4FM and CQPSK digitized signals. This is in the same ballpark as the rates used in C4FM scanners today.
It is also interesting to note how pedantic irrelevancies are raised again and again while at the same time not addressing the main message (that scanners use the wrong method when demodulating LSM)...
73
Max
* to put this in proportion, hundreds of LSM channels would fit into same 6 MHz bandwidth as used in channelized television...
Not being obtuse. It's those taking quotes out of context who are.
I agree completely with what you said provided that chip is all that is needed. As for the cost increase, I'm not sure I would call it trivial, but it would not be all that much.
I'm not sure how the DVSI licensing would work if that chip processes the P25 signals.
As for irrelevancies, it is also correct to point out that the circuitry from a $20 dongle alone is not sufficient as RBI and BB point out. That was my entire point. Dead on relevant. Now, who was saying otherwise? Wizmaster was.
Also irrelevant: How many SNFM (12.5 kHz) channels will fit into one TV channel. That has nothing to do with the topic. The answer is 480, BTW.
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slicerwizard
Member
No, Joe M. wrote 9600 SPS and confirmed that he meant 9600 samples per second - a useless rate that shows he needs to brush up on the subject matter.
With respect to the dongles you keep harping on, LSM and C4FM both need the power of a PC to process. So your point is... that you have no point. As usual.
Yes, of course he is.
KA1RBI
Member
This is a very interesting area for speculation. As I see it there might be two broad paths forward
(1) add a low KHz 4th IF centered at (say) 24 KHz and connect a wire from the output of the 4th IF amplifier stage directly (possibly via a DC-block capacitor) to an input line on the DSP chip. (No need for discrete I/Q or baseband demod chips or other hardware which would be overkill for P25 and other similar usages). This approach would retain the one-channel-at-a-time narrow-IF operation used in scanners today. It requires minimal hardware changes to existing designs.
(2) build a piece of scanner hardware that uses an ordinary smartphone platform as a starting point, with an added SDR chip*. We may call this wide band option a "modern scanner", allowing the system to eat an entire band of frequencies, including entire trunked system(s) at one time.
It's difficult to argue that the wholesale per-unit hardware costs to add option (1) would be more than, say $20. As for the hardware costs of (2) - we might form an initial estimate of this value by summing the costs for a phone/tablet, a USB-host adapter, and a $20 RTL stick. These would likely start out as retail numbers, so we'd have to discount that to get the wholesale values...
73
Max
*or just re-use the phone's existing on-board RF hardware
Which is my point of contention. It may not significantly increase the cost for Uniden to add the chip (chip cost only), but anyone who thinks it isn't going to significantly increase the price to consumers after things like re-engineering the board to integrate the chip, the costs with rolling out a new model (re-engineered board will have to have new FCC type acceptance, new DVSI liscensing, new marketing campaign for this "new" capability, etc.) is being purposely obtuse.
Yawn......
FINALLY some intelligent conversation. Wiz was dragging my IQ down.
As for the tablet, there are some <$80 tables out there these days, and that includes Win8.
slicerwizard
Member
Doesn't Uniden already do that with any new model? Why would adding proper LSM reception to the next wave of new models or to the current crop when they were being initially designed incur any extra type acceptance, licensing or marketing costs?
Sure, LSM would incur an engineering cost, but so does every feature. A cost smaller than some would have us believe. And being the very foundation of reliable decoding, it's one of the features that most warrants its cost.
KA1RBI
Member
It's quite conceivable that the current scanner manufacturers have looked at what happened with the cheap Chinese import radios (such as Wouxun, Tytera et al) and the way some of the more traditional vendors have had their lunch eaten by them. They may sense that the writing is on the wall and may be wholly unwilling to invest the sums necessary to produce anything beyond the endless repetitive variations of the same-old. After all there are virtually no R&D costs when re-using existing designs.
This is what they had to say in another thread
The impending expiration of the IMBE patents may be a double edged sword. There may be a flood of new, cheap vocoder chips but at the same time existing designs would need to be redone to interface with them. Naturally, the specific nature of the "licensing costs" wasn't detailed, but they may include other licenses beyond the MBE codec...
73
Max
This is what they had to say in another thread
The impending expiration of the IMBE patents may be a double edged sword. There may be a flood of new, cheap vocoder chips but at the same time existing designs would need to be redone to interface with them. Naturally, the specific nature of the "licensing costs" wasn't detailed, but they may include other licenses beyond the MBE codec...
73
Max
IMBE patent expiration will not materially affect new (or existing) scanner cost or development any time soon, as APCO Project 25 Phase 2 implementation requires AMBE+2. The latest patent in that portfolio expires in 2025.
Yes, they do. The MSRP has increased with every new feature set they add, while making minor changes to the existing technology. Just look at the original MSRPs of the digital era (785D/250D through 536HP/436HP) and you will see that. Now add in a new component to be added to and existing design and to not expect a larger increase than what has been steady since the rollout of digital scanners is foolish.
It wouldn't incur additional costs. It would be assigned an actuarial vale by the bean counters, and if it was anticipated to set the radio significantly apart from the competition, that value would be considered higher, and would markedly increase the perceived market value, which would increase the MSRP. No one seems to get the fact that there is absolutely NO correlation between cost and price. If they put it in, they're gonna charge a significant amount because it's something the customers want.
The MSRP may have increased, but the street price during that era has decreased.
A 250D with the P25 card was around $800. The 436 is around $500.
The big drop was around the BCD396T era - a time when scanners got more compact, too.
But in general I agree with what you said, Ed. But I believe the costs would increase, too.
A 250D with the P25 card was around $800. The 436 is around $500.
The big drop was around the BCD396T era - a time when scanners got more compact, too.
But in general I agree with what you said, Ed. But I believe the costs would increase, too.
The digital card was an additional feature that wasn't included with the radio though (sorry, couldn't resist)
slicerwizard
Member
Well, that's their call. If it doesn't hurt sales, good for them. If it does, they'll lower the price. It's not a case of "Darn, if we do this, we'll jack up prices to match our perceived value of this feature, but then sales will tank, so we can't do it."
It could tank sales of older models though...
True for the 250, but for the 296 it was a standard option.
The 250's P25 card only worked on P25 conventional systems. I'm sure there are those who are still waiting for the P25 trunking card they believe should have been forthcoming. (to extend the humor)
As for the prices, maybe they were down due to the issues which are getting resolved, so no need for discounts any longer.
D
darunimal
Guest
Everyone remember Voyager doesn't have LSM issues so he can't speak about them, he also programs Motorolas. So to him Uniden doesn't have LSM issues and further more neither does Motorola, because they "aren't" showing up on his "local system." with either "Uniden's" or "Motorola's" radios.
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