[FedCom] Re: Unknown Frequencies (J Doe) - Is that your real name?

[Chris Parris]

----- Original Message ----- >
> The repeater stays hot because it's a Motorola Quantar which understands
> Securenet. A Quant is not a simple passive repeater - it actually
> understands the data being sent to it (Securenet, ASTRO in later firmware
> revs) and munches on that data on the way through. Thus, it knows when the
> incoming signal is a digital flavor to be repeated and does so.

Thanks for that explanation. The info I had been given about the preamble
opening the repeater was from quite a few years ago, so I may have mis-filed
it in the memory cells...

> Wrong. 12K CVSD Securenet is already pushing the 5KHz channel to its
limits
> as far as information capacity is concerned. Chopping off the bottom 300Hz
> for PL/DPL to pass means there's not enough bandwidth left to pass the
> digital data through.

And that was what I meant to say - that there is no CTCSS transmitted during
the digital data transmission. But I do hear a valid CTCSS tone occur during
the brief key-up prior to digital voice, so I'm guessing that one could
still select repeater sites by CTCSS tone when used in conjunction with
digital encryption. Or would that even be nessesary? Can the Quantar
repeater be configure to open only with the correct CTCSS for analog or a
valid Securenet data stream for digital?

- Chris

 --
Chris Parris
Fed Files Columnist
Monitoring Times Magazine
chrisparris at monitoringtimes.com
Fed Files Blog - http://mt-fedfiles.blogspot.com/