P25 Simplex

[K6GBW]

My little group of hammies have recently started playing with the higher power Motorola VHF XTL 110 radios. We use them both as base radios and in some of the cars. The range we're getting on simplex is amazing! We've been sort of refocusing a bit on VHF simplex in case our local repeaters go down after an earthquake or some other problem that always seems to crop up. The 2 meter band on digital simplex is giving me a reach of about 35 miles in any direction. The LA area is covered by mountains so there are some dead spots, but man it's nice to have the ability to reach out and touch someone at that kind of range. I'm currently working on a new antenna and a small tower to give it even better reach. If you haven't played with simplex in a while it's time to give it try!

 

[K9KLC]

I use use and have used 2 meter fm simplex for some years now after doing mainly 70cm and 1.25 meter both simplex and repeaters l. Never did much on 2 meters as far as repeaters unless it was on the weather nets or similar.

We are doing FM and DMR here but, I just got done talking to a couple friends on 2 simplex DMR and said we needed to try P-25 as a couple of us have radios sitting around that will do that. I need to get some software for these old Motorola's we have and see about getting them programmed up and on the air.

Great post, thanks for mentioning it. Maybe we'll get a fire lit now and actually do something.

 

[kayn1n32008]

A bunch of us locals are using P25, but on UHF. Usually on our local P25 repeater. We use UHF P25 simplex when we convoy. VHF is horribly noisy, here.

 

[vagrant]

P25 is delicious. I recommend it for most everyone via simplex or repeater.

 

[K9KLC]

P25 is delicious. I recommend it for most everyone via simplex or repeater.

I have only briefly tried it a while back and it sounded pretty good I'll admit that. I'll have to get my stuff dug out and programmed up and give it a go!

 

[Project25_MASTR]

I have only briefly tried it a while back and it sounded pretty good I'll admit that. I'll have to get my stuff dug out and programmed up and give it a go!

The firmware development has never ended as the DSP modules within the radios has gotten better over the years. A first generation IMBE radio (like an Astro Saber, 5100, etc) versus the second generation radios like the IMBE based XTL/XTS or AMBE2+ based radios (APX, 5x00ES, SRM9000, etc) is night and day difference. Now as we get more mature into the 3rd generation (Phase 2 capable) radios things are continuing to improve. A modern BKR/APX/Viking/etc sound great compared to those old first and second generation radios.

 

[K9KLC]

The firmware development has never ended as the DSP modules within the radios has gotten better over the years. A first generation IMBE radio (like an Astro Saber, 5100, etc) versus the second generation radios like the IMBE based XTL/XTS or AMBE2+ based radios (APX, 5x00ES, SRM9000, etc) is night and day difference. Now as we get more mature into the 3rd generation (Phase 2 capable) radios things are continuing to improve. A modern BKR/APX/Viking/etc sound great compared to those old first and second generation radios.

I seriously doubt I'll ever have the Money to spend on an APX. I have an extremely early astro saber, which was given to me and some kind of HT that has FPP enabled on it. (I forget what that is but it's old also). I may eventually see about an XTL mobile I guess I need to see about programming it or even getting the software. I looked on my Motorola account after this thread got started and I don't see it anywhere on there except for the APX stuff and, I don't know if that will work.

All in all, I'm definitely in for trying a new digital voice mode simplex. A few of us use 99% simplex around here with the exceptions of storm nets or such, and that would be nice to try.

We do use some DMR now and have multiple radios for that already. I think there is at least one P-25 repeater in the area so that's something I guess. Problem would be getting everyone else that already has DMR to switch to P-25. We're just a bunch of poor old hams so you know...

 

[kayn1n32008]

The firmware development has never ended as the DSP modules within the radios has gotten better over the years. A first generation IMBE radio (like an Astro Saber, 5100, etc) versus the second generation radios like the IMBE based XTL/XTS or AMBE2+ based radios (APX, 5x00ES, SRM9000, etc) is night and day difference. Now as we get more mature into the 3rd generation (Phase 2 capable) radios things are continuing to improve. A modern BKR/APX/Viking/etc sound great compared to those old first and second generation radios.

This. 1000% this. Even the XTL/XTS 2500/5000 series are NOT anywhere near the same as the early Astro Saber/XTS3000. the problems that FDNY had with P25 just simply do NOT exist any more. Motorola has spent a lot of money on DSP/active noise cancelling technology over the past 25+ years and it shows. they filter PASS alarm and will all but eliminate background noise, when using a multi-mic speakermic. Nobody comes close to Motorola audio.

I seriously doubt I'll ever have the Money to spend on an APX.

I definitely don't have the money for an APX.

I have an extremely early astro saber

Keep it as an analogue radio, or put it on a display shelf.

I may eventually see about an XTL mobile

IF you are patient, and wait for a good deal, there is no reason that you can not find a decent XTL5000, with a full remote kit and a O5 control head. If space is limited, keep your eyes open for a O3 HHCH. \

You should be able to get a good mobile for $350 or less. Also keep an eye out for a XTS2500 or XTS5000.

You should be able to get one in the band split you need for $300 or less. I bought a VHF XTS2500 with antenna, charger and battery for under $250, as a bonus it had a UCM and AES 256 and AES GCM. I got 2x PRC-153(XTS2500 UHF-R1) that i modified for proper back light, for something like $175/ea. Both had UCM's with AES 256 and AES GCM.

I guess I need to see about programming it or even getting the software. I looked on my Motorola account after this thread got started and I don't see it anywhere on there except for the APX stuff and, I don't know if that will work.

For the XTL1500/2500/5000 mobiles, you need ASTRO25-Mobile CPS, for the XTS1500/2500/5000 portables, you need ASTRO25-Portable CPS. both are easily acquired if you google their names, i suggest looking at W9CR web site

All in all, I'm definitely in for trying a new digital voice mode simplex. A few of us use 99% simplex around here with the exceptions of storm nets or such, and that would be nice to try.

Digital voice is great on simplex. No squelch crashes, no static, no picket fencing. just nice clean, readable audio.

We do use some DMR now and have multiple radios for that already. I think there is at least one P-25 repeater in the area so that's something I guess. Problem would be getting everyone else that already has DMR to switch to P-25. We're just a bunch of poor old hams so you know...

Once you use P25, and hear the audio difference between P25 and DMR, you will not want to go back to DMR.

 

[prcguy]

My little group of hammies have recently started playing with the higher power Motorola VHF XTL 110 radios. We use them both as base radios and in some of the cars. The range we're getting on simplex is amazing! We've been sort of refocusing a bit on VHF simplex in case our local repeaters go down after an earthquake or some other problem that always seems to crop up. The 2 meter band on digital simplex is giving me a reach of about 35 miles in any direction. The LA area is covered by mountains so there are some dead spots, but man it's nice to have the ability to reach out and touch someone at that kind of range. I'm currently working on a new antenna and a small tower to give it even better reach. If you haven't played with simplex in a while it's time to give it try!

Send me your P25 simplex freq!

 

[mikegilbert]

I had some simplex P25 communications from atop Mount Wilson to a building across the street from John Wayne airport back in 2021.~39 miles!!! Blew my mind!

Just realized my license has lapsed, and I missed the renewal window so I've gotta start fresh again. Whoops.

 

[vagrant]

I use both VHF and UHF XTS5k model 3 handhelds with FPP. I found them on eBay and QRZ for under $200. They are an affordable way to get started. They are definitely better than the Astro Saber which I used in the past. I use an XTL5k in the vehicle.

I also use a VHF/UHF APX 7000xe handheld. I’m fortunate here in central California as there are linked and standalone repeaters, so the handheld gets in fine.

I still use P25 simplex with a couple of buddies from time to time. We are lucky though that the standalone repeaters are typically not busy. The only issue is when operators aren’t using tone squelch, get blasted with P25, then kerchunk the repeater on analog.

 

[Motoflightmedic]

For you guys just jumping off into the Astro25 line of radios, ill give you a couple of recommendations. make sure they are on a later version of firmware 19 or 20.

I would suggest to start here with these TX audio settings in your XTS/XTL radios. I have found that this provides the most natural sounding audio across my radios with a variety of users. including men, women and kids.



I would also set your RX audio to the following



As always your milage will vary but this is how i have setup my radios and still use them today. I have been rolling with XTS and XTL radios for the better part of 15 years.

 

[Motoflightmedic]

Once you use P25, and hear the audio difference between P25 and DMR, you will not want to go back to DMR.

I agree with this for the most part, and i love p25, but i recently acquired a Kenwood Viking VP8000 and the DMR audio on this radio is 10x better than my XPR7550s. I would honestly say the DMR audio on this VP8000 sounds more like P25 than what i typically think of when it comes to DMR. I also just picked up a NX5800 in low split and i am planning on using it primarily on DMR. I'm anxious to see if sounds as good as the VP.

 

[N4DES]

The firmware development has never ended as the DSP modules within the radios has gotten better over the years. A first generation IMBE radio (like an Astro Saber, 5100, etc) versus the second generation radios like the IMBE based XTL/XTS or AMBE2+ based radios (APX, 5x00ES, SRM9000, etc) is night and day difference. Now as we get more mature into the 3rd generation (Phase 2 capable) radios things are continuing to improve. A modern BKR/APX/Viking/etc sound great compared to those old first and second generation radios.

Totally agree, it was around FW 17 of the X series that Motorola made a tremendous upgrade to the IMBE DSP that really made a difference.

P25 in VHF and 800 MHz for me. UHF remains DMR because that's where the majority of the local users are and I own/operate a UHF repeater connected to the MARC network.

 

[jeepsandradios]

Been using P25 simplexe for years both at work and SAR stuff. I have a 2m P25 simplex channel setup at home I use as well when I'm out. I have them in every band but VHF is used 99% of the time. The adantage of P25 is not many have the radio so its pretty nice. Additionally so far there are no CCR P25 radios so you donth ave to deal with those audio issues.

 

[exkalibur]

Agreed. People that are used to the P25 audio from an older XTS3000 or from a scanner aren't really experiencing modern P25 audio quality. Audio on a modern P25 using AMBE+ sounds light years better than the old IMBE stuff.

 

[K6GBW]

Glad to see this topic is interesting to at least some of us here! I spend the vast majority of my time on HF, but as we start down the slow path toward the bottom of the solar cycle I thought it was time to focus on "local" communications. We are way overdue for a big shaker here so it seemed prudent. I also volunteer with the local Sheriff's department doing their version of ACS and they focus mostly on 2 meter, so that fit into the mix as well.

I do use DMR pretty extensively, but I can find it frustrating at times. Sometimes I'll be talking to a friend on a local talkgroup and then suddenly we're getting bonked. The local repeater has about a dozen talk groups connected to it so it can create a bit of a traffic jam. I find that simplex, without the associated complications of repeaters to be much more to my liking. The fact that P25 cleans up the signal on the fringe areas is a great bonus. It seems to give the radio a little more usable range. I also find P25 much much easier to program.

It's a shame that the ham radio community has become so fragmented over the last ten or fifteen years. DMR, D-Star, YSF...the list goes on. Of all the available modes I really like P25 the best. The audio sounds great, especially on the newer radios, and all you really need is the frequency and the NAC and you're done. The user base is also starting to get a bit bigger. There are several P25 repeaters around LA/SoCal now so it's really starting to pick up. I'm looking forward to what the future brings!

 

[Project25_MASTR]

P25 at it's most basic configuraiton is almost a 1:1 for analog. Frequency and instead of a PL/DPL you have a NAC. Now you can add talkgroups to that (I'd avoid it if all possible) and other things, but most don't for conventional operation. Far simpler to hand jam in a BK than a DMR FPP system is to hand jam...

 

[K6GBW]

I seriously doubt I'll ever have the Money to spend on an APX.

You might be surprised, I've found some really good deals over the last few months. I've picked up several XTS adn XTL models and I do have an APX8K that admittedly cost me a bundle. But, after aquiring it I found I really didn't use it as much as I thought I would so it sits around much of the time. My go to drag around daily radio is a simple XTS1500 M1.5. It gets the job done and set me back $200!

 

[prcguy]

I as able to contact K6GBW on his 2m P25 simplex freq at 5w into a lousy antenna over a surprising distance. Worked great!