[OZAPRS] UHF APRS freqs in VK

[Scott Evans]

Well bandplans come and go and I'm really struggling to get my head around
the 5/7 splits just to avoid the LIPD allocation. Ok yes there's some
sections of the 70cm band that have dedicated use (space, weak signal etc)
another frequency allocation that is just silly, 439.200 being set aside
for digital voice (P25, DSTAR, DMR and C4FM) also doesn't quite make any
logical sense to me. But what would I know? 🤔

On Sun., 12 Nov. 2017, 19:32 Glen English VK1XX, <
glenlist at pacificmedia.com.au> wrote:

> Hi Scott
>
> yeah 439.1 which is USELESS DUMB IDEA I EVER HEARD OF , I see it in the
> bandplan.
>
> why ? because it is too close to easily diplex into existing 70cm
> repeater systems that it might have to share with. Whoever came up with
> 439.1 had NFI.
>
> Two problems
>
> 1) requires lots of filtering and or loss to combine with 438-440
> transmitters
>
> 2) Because the digi would need to RECEIVE next door to the 70cm repeater
> transmitter, it will just get knocked over with TX noise unless you
> throw something like 3 x 6" 3/4 wave cans at it.... like no way.
>
> Canberra city is going on 442.975
> Ginini will go on 442.775 , tentatively, barring staying out of the way
> of numerous UHF repeater links..
> Maybe they should go on 12.5k offsets to stay clear. hmm.
>
> 200kHz apart in the same region is far enough that sidebands and spurs
> from one TX (say on 442.775) will not get into the other receiver (say
> on 442.975)
>
> :-)
> g
>
>
>
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