Astro Spectra Plus,, no P25 modulation OOB

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mogman
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Astro Spectra Plus,, no P25 modulation OOB

Post by mogman »

Just wondered if anyone else has seen this issue and possibly has a fix.
Astro Spectra Plus R split will TX/RX analog down to 430 MHz (with mods) no problem.
It will mod P25 anywhere above 450 MHz with no problem, but ZIP, ZERO, NADA anywhere below 450 MHz, just carrier, no digital stream at all.
Pop in an Astro Spectra Digital VOCON and no problem with P25 mod below 450 MHz (initial testing)
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d119
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Re: Astro Spectra Plus,, no P25 modulation OOB

Post by d119 »

Probably due to there being no tuning values for the frequencies you need. Without using unmentionable software, you're probably stuck.
mogman
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Re: Astro Spectra Plus,, no P25 modulation OOB

Post by mogman »

Not a tuning issue, same soft spots as the Astro Spectra Digital and it works fine all the way down to 430 MHz, there is something in the Plus codeplug preventing P25 modulation even just 1 MHz below the factory split.
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W3AXL
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What radios do you own?: an unhealthy amount of them

Re: Astro Spectra Plus,, no P25 modulation OOB

Post by W3AXL »

If you can TX/RX analog no problem, and it sounds like you're deviating properly, that truly does sound like the same sort of codeplug limitation that some of the regular Astro Spectras had which required some tricky editing to work around.

Interestingly none of my R-split Astro Spectras had this limitation so I never had to deal with it. As it so happens I've got an R-split Plus on the way, and I'll try and get it programmed up and let you know if it works in the ham bands.
motorola_otaku
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Re: Astro Spectra Plus,, no P25 modulation OOB

Post by motorola_otaku »

This is a known issue with AS+ radios. The "artifical limit" imposed by Motorola in the codeplug is not accessible using readily-available software tools or methods.

You can roll it back to a regular Astro Spectra with a VOCON swap and blast in current firmware... it will modulate P25 from 440-450 normally after that.
mogman
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Re: Astro Spectra Plus,, no P25 modulation OOB

Post by mogman »

Thanks, yes I know it works as an ASD,,, the guy I am trying to help out wants aliasing so I am looking for a "fix" for the "artificial limit" in the Plus codeplug, if it is possible within reason.
motorola_otaku
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Re: Astro Spectra Plus,, no P25 modulation OOB

Post by motorola_otaku »

It requires access to the memory using a tool that we commoners are not likely to ever possess... and I don't mean Depot. If someone has a modified codeplug you might be able to clone it in using regular CPS.

I just accepted that I couldn't do it in an AS+ and either rolled them back to regular Astro Spectras or switched to a different model.
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W3AXL
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Re: Astro Spectra Plus,, no P25 modulation OOB

Post by W3AXL »

I might try and play with my Plus a little bit. I'm wondering if an "upper" cutoff frequency for P25 is programmed in to the Q-split tuning partition. 440 is quite a far distance from the last tuning softpot but I'd be interested to know how far up the deviation and tuning interpolates and stays good.

I know some people use the standard Q-split Astro Spectras in the ham bands so it's worth a shot on the plus.
mogman
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Re: Astro Spectra Plus,, no P25 modulation OOB

Post by mogman »

Thanks again, well we will let it "float" for a while and see if anyone has that codeplug or some other idea.
radiodude123
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Re: Astro Spectra Plus,, no P25 modulation OOB

Post by radiodude123 »

I've never got a Q split to go over 440. What's the secret ?
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