[TheList] Northland Police data noise

Mon Aug 1 05:11:16 AEST 2016

Interesting! Thanks for that reply, nice to have my theory confirmed.  I thought I was right, but the Northland channel is the only channel I've heard it on.   It's a good idea to have though, a customer of ours has something similar set up on a site South of us, although they do have mains, the hill is helicopter access only and basically only in summer.  It has a massive battery bank as the hill can stay in cloud for a solid week I'm told. 

Cheers! 

Richard / Z-master 

On 31 July 2016 10:10:15 PM NZST, Ian Stewart <nzlegs at gmail.com> wrote:
>I have to admit, it was me that installed that system. About 10 years
>before I retired 15 or so years ago.  The telemetry transmitters are at
>each repeater site, a  number of them. They come in 2 Flavours, analog
>and
>completely digital. Analog ones also support the digital 'channels'
>that
>the digital transmitters send, ie 'ÒN' and 'OFF' . Analog ones also
>send
>battery voltage via a analog to digital converter. It is a really
>simple
>system, 300 baud from memory, based on AX25 protocols. All TTL so
>fairly
>old now. Ďecoding would be worthless - you would have to know what each
>channel means. I have forgotten.
>
>Ian
>
>On 31/07/2016 9:27 PM, "Chris Hoffmann" <chris021 at gmail.com> wrote:
>
>> I have always thought it was battery levels from solar repeaters, but
>have
>> never tried to decode it.
>>
>> On 31/07/2016 8:40 PM, "DogSecurity - Richard"
><richard at dogsecurity.co.nz>
>> wrote:
>>
>>> Hey guys,
>>>
>>> I was up in Whangarei last night doing some geocaching (could have
>picked
>>> a better weekend....) anyway each time I've gone up, when I've been
>>> listening to the police channels, I sometimes hear some type of data
>tone.
>>> It's obviously some type of SCADA/data transmission although I can't
>pick
>>> what it is just by listening. What I'm curious about is... what is
>it for?
>>> are they monitoring a remote solar site for battery stats?
>>>
>>> Cheers,
>>>
>>> Richard / Z-master
>>>
>>>
>>>
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