APCO 25 simplex

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wb6sub

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I have 2 Motorola XTS5000 1 in 2 meter and the other in 70 cm. I am interested in simplex frequencies I could use that other hams are using for APCO 25. I live in Southern California High Desert
 

KG7PBS

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well i would put in 146.50 NAC 293, with Digital CSQ 446.000 same as last, i will find a few more for you there are a few P25 repeaters do south of you i can dig up
 

KC8ESL

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For Cleveland simplex we are primarily using 446.825 nac293, though I do have 446.000 and 446.100 set for p25 as well. Obviously this is just what our group uses, but I wouldn't be against conforming to what a majority use.
 

zz0468

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I have 2 Motorola XTS5000 1 in 2 meter and the other in 70 cm. I am interested in simplex frequencies I could use that other hams are using for APCO 25. I live in Southern California High Desert

Go to the TASMA and SCRRBA web pages, and look up the band plans. Both will show what the simplex frequencies are.
 

box23

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should I use narrowband @ 12.5 khz or standard 25 kHz?

It depends on how you have it programmed as it is an analog only setting. If set to ASTRO only for both Transmit and Receive it doesn't matter since digital operation will always be narrowband (12.5kHz).

If using mixed mode you should set it to the proper bandwidth for the frequency being used which is usually wideband for VHF/UHF amateur but there are a few groups that I know of that use narrowband.
 

wb6sub

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I checked out TASMA and SCRRBA and the only thing I found for simplex digital voice was one channel 449.4625 and in the 2 meters band plan was only digital voice repeater pairs none that were simplex
 

zz0468

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I checked out TASMA and SCRRBA and the only thing I found for simplex digital voice was one channel 449.4625 and in the 2 meters band plan was only digital voice repeater pairs none that were simplex

449.4625 is NOT a simplex channel. That is the digital repeater test pair. There are test pairs assigned for garage repeater testing. 446.86 and 446.88 are used for standard FM repeaters. Since digital operation is of interest to a lot of potential repeater builders but completely incompatible with shared analog use, a digital only test pair was created.

So, there's the answer to your original question. There isn't sufficient organized or documented P25 simplex activity to warrant any band planning effort to set aside a dedicated simplex channel, therefor none exist.

On the two meter band, there are two segments assigned for unchannelized simplex operation. If you're starting from scratch with a few other hams wanting to try it out, that might be a safe place to go without fear of bothering anyone.

I'd drop an email to both groups and ask THEM the question.
 

zz0468

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well i would put in 146.50 NAC 293, with Digital CSQ...

Here in Southern California, that would land you on an analog repeater input.

...446.000 same as last, i will find a few more for you there are a few P25 repeaters do south of you i can dig up

And the local band plan specifically prohibits digital operation on this one.

When someone is looking for local amateur frequency information, it's probably a bad idea to suggest specific frequencies unless you're very familiar with the local customs of the target area. Some places do things completely different than others. Tromping through someone's analog repeater input with a P25 radio could be VERY aggravating.
 

wb6sub

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I am trying to adhere to the local coordinating like SCRRBA and TASMA have come up with. Thank you for the warning. Maybe SCRRBA and TASMA one day will come up with simplex frequencies for digital voice.
 
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