P25 phase2 tdma as conventional?
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troymail
Silent Key
No - I am not aware of any scanner (or other radio?) that will decode Phase 2 as conventional.
troymail
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kayn1n32008
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‘Simulcast distortion’ is caused by the HARDWARE not being compatible with the waveform used in ‘LSM’ the only real way to fix it, is to design a receiver to handle receiving LSM.
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I understand the OP's concept, let's try monitoring the channels as conventional rather than trunked mode to see if it will work better for LSM. I assume that he has a Phase 2 system there.
Unfortunately I don't think it would work. I did try this for grins and giggles a few years back on a Chicago area Phase 1 system (that has since updated to Phase 2). There was no improvement.
My idea at the time was to see if I could demodulate the P25 voice and use something like PRO96Com or UniTrunker to control the radio.
As an aside here, AFAIK there are no P25 radios that will allow one to use TDMA in a conventional mode. I don't ever recall seeing that option in the APX software and have never heard of it being done. I suppose it is possible, they are doing that with DMR so why not P25? If it happens to become a thing I would imagine that Uniden (and Whistler) would respond and add that to scanners.
Unfortunately I don't think it would work. I did try this for grins and giggles a few years back on a Chicago area Phase 1 system (that has since updated to Phase 2). There was no improvement.
My idea at the time was to see if I could demodulate the P25 voice and use something like PRO96Com or UniTrunker to control the radio.
As an aside here, AFAIK there are no P25 radios that will allow one to use TDMA in a conventional mode. I don't ever recall seeing that option in the APX software and have never heard of it being done. I suppose it is possible, they are doing that with DMR so why not P25? If it happens to become a thing I would imagine that Uniden (and Whistler) would respond and add that to scanners.
kayn1n32008
ØÆSØ
It’s a hardware issue, not something that can be changed by changing programming.
Conventional TDMA, and TDMA on simplex has not been written into the P25 standards, there fore it is not available on P25 subscribers.
see above.
And likely be added to subscriber radios as well. I doubt it will be added. But the possible reasons why are for another thread.
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Yes, as I alluded to later in my post. Good idea for something to try but it wasn't the issue or solution.
That hasn't stopped Motorola from "adding features" that seem to restrict systems to their radios and exclude others. There is nothing stopping Motorola or the others from implementing this if they choose to.
kayn1n32008
ØÆSØ
But neither Motorola, or any other manufacturer of P25 phase 2 equipment, has added their own proprietary version of conventional or simplex TDMA using the P25 CAI. DMR can do both conventional and simplex TDMA.
IMO, it would be ‘bad for business’ having conventional TDMA using the P25 CAI, simply because it would give small and medium size organizations a cheaper option than P25 trunking to realize having 2 talk paths on a single 12.5KHz channel. That is the more likely reason for manufacturers not implementing conventional P25 TDMA.
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I know the above method will not overcome the distortion completely but without a distorted CC, I can reasonably hear the VC's. I have been doing this with a phase 1 simulcast system for some time.
Trunking mode seemed to make it harder to hear anything.
I realize the scanners do not have the proper electronic design to handle LSM and the G5's do.
I only do this for convenience sake. When i only have 1 radio with me and have no choice but the attempt.
Trunking mode seemed to make it harder to hear anything.
I realize the scanners do not have the proper electronic design to handle LSM and the G5's do.
I only do this for convenience sake. When i only have 1 radio with me and have no choice but the attempt.
It is not possible to decode TDMA in conventional mode. The only digital system that can be scanned in conventional mode is p25 standard conventional
DHAS12
Member
My whistler WS1080 has an option in the search menu for Phase 2 along with Phase1 and DMR. Not sure if it decodes the voice, or if it just finds P2 Voice channels I have never tried it.
troymail
Silent Key
I think you mean the option(s) to filter and stop on only selected digital modes -- not anything specific to Phase 1 or Phase 2 (it just says "P25", correct?). I could be wrong but I don't think that option will do anything with an active Phase 2 voice frequency.
I now understand that the OP was going to input the input frequencies (which would not be subject to simulcast since it is one signal coming from a single location). However, such signals are severely range restricted and are typically blocked by terrain within a couple of miles (unless you have a tower-mounted antenna). And, they aren't decoded by scanners.
troymail
Silent Key
I don't think he planned to use the input frequencies - at least, I don't see (read) him saying that.
I believe he is saying "bypass the control channel" and enter the voice (repeater) frequencies as conventional. For some systems - particularly Phase 1 simulcast systems, this removes a layer of issues in that you don't have to rely on the scanner properly receiving and decode the control channel first before getting to the (garbled) voice channel....
Many times, I recommend users try this if they are having problems receiving a system.
If you don't receive the control channel well, you're never going to get to the voice channel....
Of course, not using the control channel introduces other problems....
Ok. In that case, no real reason to do it.
Even if you did, and no reason at all, what about the other 4,5, or 6 of the trunked freqs? You would need to have every one to follow anything.
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