[Dstar] Intro and some questions.

[Tony Langdon]

At 10:31 PM 12/19/2007, Michael Carey wrote:


>At this stage I'm looking at a 70cm repeater, mainly because there 
>is an unused 4 stack UHF dipole antenna on the tower ready and 
>waiting for some RF to be pumped through it, I've already checked... 
>it works great on 70cm.
>Now for my questions... how "immune" is a 70cm D-Star repeater from 
>LIPD interference? We have moved the 70cm repeater to

There is a simple cure for LIPD interference, Victoria has started 
the precedent, and it is written into the band plan.  D-STAR 
frequencies use outputs below 438.400 with a 5.4 MHz split, which 
puts the input below 433 MHz (and out of the LIPD band).

As for pagers, Steve re-iterates what I heave read in that the 
repeater front end seems to be a bit prone to intermod, so a good set 
of bandpass cavities will be needed, and maybe some additional 
notching of pager frequencies on 2m.

>439.850MHz to get away from persistent problems on the old input 
>frequency of 433.225 MHz. Is a D-Star repeater located in the same 
>repeater section of the bandplan? Has anyone on this list had 
>problems with 70cm D-Star repeaters and LIPDs or 2m D-Star repeaters 
>and pager interference?

Have a look at the bandplan at www.wia.org.au.  It will answer your 
questions, but in short, these are the recommendations:

2m - Lower half of the repeater band, on frequencies with a 12.5 kHz 
offset (i.e. in the guard band between FM repeaters).
70cm - Below 438.400 MHz with a 5.4 MHz offset.

>How bandwidth-hungry is a D-Star repeater? I'm able to utilise an 
>existing ADSL connection, but I don't want to hammer the owners 
>download limit or hog the connection during a D-Star QSO.
>I'm not afraid of Linux, I love a challenge, and would love to get 
>something happening over here. We will have three D-Star operators 
>within two months and probably more as the new year marches on. The 
>time is right to get the ball rolling.
>I look forward to replies, suggestions and comments.

I can't answer that, but there's a number of gateway operators here 
that can. :)

In any case, looking forward to seeing you guys on board. :)

73 de VK3JED
http://vkradio.com