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dStar Experiment:7 Jan 2012-01-07
Today saw the experiment I have been wanting to do since starting with the dstar repeater setup.
Aim: To see if a standard off the
shelf Ham crossband radio will crossband the dStar dtar stream.
Today I tested this theory with
an Icom IC-2800 radio in crossband
mode.
The experiment was a 100% success
in both vhfto/from UHF.
This would allow us to expand the
dstar to some areas WITHOUT the dedicated
resources such as the dstar dongle /PC and
internet.
Using this one can provide a star
network from a main dstar repeater
.
There is no reason why even crossband portables could be used- will test my IC-78
soon .
This will certainly open up a lot
more avenues and self experimentation for the ham wanting to get involved
in dstar.
I am not saying that ALL crossband radios will do this as one has to
appreciate that the radio should pass from Discriminator out to flat tx input in order to pass the digital data
stream.(Hopefully your crossband can do this )
The audio was 100 % and proved
the theory .
Best practice would be to get a
very good incoming signal path to the donor dstar
that you want to work off.
Good luck with your own
experiments- do drop me an email if you are
successful.
Regards ZS5BG
Repeater Work: 06 Jan 2012
Alverstone 145-000 RX site
planned work.
(RX leg of the split site repeater 145-600)
Installed Polyphasors and earth
to our equipment-
VHF RX 145-600
UHF 431.625 to PMB
channel 2
First two positions from left.
Repeater Work: 05 Jan 2012
Repeater UHF dstar installation Kloof hisite:5 Jan 2012
Completed dstar installation at
Kloof hisite ,first dstar repeater in
the Harc area.
This temp installation is until the excess equipment is
removed from container and we can mount in dedicated 19” cabinets
that are on site .
For this exercise I have taken the HUB 434-650 off air
till further notice.
Channel 7 dstar uhf is using the
collinear AR-12 at top level of tower.
Frequency-439_325 Mhz (-7.6mhz
split).
Currently in standalone operation until the internet
access to the site is arranged .
The cavities (Kathrein) make for
a perfect UHF duplexer but has 3dB loss per cavity – but well worth
it .Each cavity consists of dual cavity sections with a window between
them – top design by Kathrein.
From left is Motorola M120 – middle is the Satoshi
board and breakout box –PTT and COS line enable /disable for my own
reasons .The Monitoring point is the BNC to monitor the data stream on
site – very useful.
On the right is the M10 UHF transmitter with its own mod-
PTT switch Normal and PTT enable .
Future : May look at a
LNA just to up the RX a few dB’s .
Many thanks to Jan ZS5JC who provided the Sotashi dstar board for
this project.
Repeater Work: 23 June 2007
--Made
off connectors for remaining 3 cables from container to base of tower.
--7/8 cable
is now terminated to the UHF yagi facing Alverstone as a temp patch for the UHF repeater ch1
in container.
  
First picture : Base of tower where our feeders
are connected to runs going vertically up the tower.
Second Picture : Preperation to terminate link antenna connector.
Third Picture: Picture of Ham Container (door
open )
Ch1 : OFF AIR
Ch2: Frequency used by MARC
club for their wide area linked repeater system.
Ch3 :Standalone (No HUB)At this stage there
are no plans to change anything at this site and it has been working well
.
Ch4 :Bluff is requiring new feeders to
be put up after the radio company replaced the mast due to weathering .
Ch5 :
Ch6 : Back up and running
standalone .
Ch7
:Now dstar repeater at Kloof
145-600 Linked to PMB linked repeater MARC
network
145-625 : This repeater also has moved to the external
container at Kloof .
434-650 : Alverstone HUB to be recommissioned –future.
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NAT.U.R.N. (Natal Uhf Repeater Network)
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