Mike_Alpha
Member
After some disapointment using the ARD25 digital decoder with my AR8600, I managed to get it going nicely with my Tait T2020 remote head, commercial radio.
The Tait T2020 mobile uses a 10.7MHz IF, so I tapped it and after a few adjustments to the settings in the ARD25, it now decodes digital transmissions very well.
Initially, the Tait IF didn't produce any results, but thanks to the help of Steve WA1YKL, I was able to invert the polarity of the signal, using the data connector and Hyperterminal. Other commands let me adjust the digital and analogue squelch levels, plus switch off an annoying 'Voice Echo" setting.
It's still a bit crackly on weak signals and some very weak analogue signals don't get passed through the ARD25, but local digital decoding is clean and when scanning there is no noise output from the speaker.
I've put some life back into a near obsolete analogue UHF commercial radio, now able to be used with APCO25 channels and I have the benefit of a commercial quality RF front end and voting capability.
Mike
The Tait T2020 mobile uses a 10.7MHz IF, so I tapped it and after a few adjustments to the settings in the ARD25, it now decodes digital transmissions very well.
Initially, the Tait IF didn't produce any results, but thanks to the help of Steve WA1YKL, I was able to invert the polarity of the signal, using the data connector and Hyperterminal. Other commands let me adjust the digital and analogue squelch levels, plus switch off an annoying 'Voice Echo" setting.
It's still a bit crackly on weak signals and some very weak analogue signals don't get passed through the ARD25, but local digital decoding is clean and when scanning there is no noise output from the speaker.
I've put some life back into a near obsolete analogue UHF commercial radio, now able to be used with APCO25 channels and I have the benefit of a commercial quality RF front end and voting capability.
Mike
