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Thread: Spectra Modulating P25 but no Voice?

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    Default Spectra Modulating P25 but no Voice?

    Interesting issue has cropped up. I've recently finished up a refurb of a UHF AS. It seems to be working very well, is on frequency, and sounds great. It's got one quirk that I can't wrap my head around. When doing P25, the radio will transmit valid P25 packets but will not pass voice.

    It's opening up our quantar just fine and all the receiving radios I've tested will decode properly, displaying the ID and everything. Just no voice. Analog TX voice works fine and sounds great with no issues.

    I can't figure out what would cause that odd behavior. Anybody with more experience have any ideas?


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    Did the radio ever work in P25 mode? What is the DSP firmware version? (including the letter at the beginning)? IIRC this is how an Astro Spectra/Saber will behave if someone hacked the flashcode for P25 but didn't load P25 capable firmware in the radio.

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    I'm starting to think that might be the issue. The radio arrived to me dead and I had to throw a new s-record in it to get past a fail 01/90. I've had units in the past that have been hacked with P25 in the flashcode on analog firmware, but they wouldn't put out anything other than a carrier on a digital-programmed channel. This one is putting out the proper P25 packets, but they're just empty without voice.

    Just checked - it's on R11.14 "A" firmware. I'm a bit fuzzy as it's been a while but I think that's the analog-only firmware? Regardless I might try and dig up another vocon and see if that solves the issue.

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    Quote Originally Posted by axel View Post
    ...Just checked - it's on R11.14 "A" firmware. I'm a bit fuzzy as it's been a while but I think that's the analog-only firmware? Regardless I might try and dig up another vocon and see if that solves the issue.
    Yup, that's an analog firmware.

    Another VOCON is in order, or re-flash that VOCON to get yourself an " I " or " N " (digital) firmware

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    Also be aware that deviation will be low in the 440-450 range on a R3 radio unless the HOST and DSP are current (R11.71.07 and N08.03.05 iirc.)
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