Category Archives: D-Star

New DSTAR Repeater in Perth

As there have been ongoing problems with the VK6RWN DSTAR Gateway server, it’s been removed from site and connected at Heath VK6TWO’s QTH for remote maintenance by the DSTAR Guru’s.

To assist in getting Perth DSTAR users back ‘online’, Heath VK6TWO is in the process of building a standalone DSTAR Repeater Node which will enable registered DSTAR users to ‘connect’ to the worldwide DSTAR network.

Testing is currently in progress and it’s expected that the node will go live late July.

23cm DSTAR Digital Voice now on air!

Perth now has 23cm DSTAR Digital Voice coverage from the Roleystone repeater site thanks to the purchase of a 23cm diplexer.

Coverage on 23cm from this site is yet to be field tested but computer generated coverage plots show that it is quite healthy.

Members are encouraged to purchase Icom ID-1 23cm DSTAR/FM mobile radios or an Icom IC-9100 (with 23cm and DSTAR options fitted) to utilise. DSTAR home brew is also becomming quite popular so perhaps give this a try too.

Thanks to Rob VK6LD for spotting the cavity purchase opportunity, and VK6TWO for the purchase and installation.

Roleystone (6RAP, 6RWN, 6RUF)

A HUGE amount of money, equipment and time has been spent on our ‘Hub’ site at Roleystone VK6RAP in the past couple of months. We have installed 3x new LDF5-50 coax runs to the top of the 80m mast, Installed new Diamond X5000 and X6000 Triband (2m/70cm/23cm) antennas, refurbished the coax/mast, tidied up the cable entry from the mast to the shack, fitted cable glands for the coax entry to shack, installed a new Diamond Triplexer, relocated and installed the 4 DSTAR repeaters and installed new WiFi data link enabling Internet connectivity for the DSTAR Gateway. Many signal reports have indicated that coverage from the site is now exceptional. Photos can be found here:


The Roleystone site has the following WARG services: VK6RAP 6m & 2m & 70cm voice repeaters, VK6RUF 70cm voice repeater, VK6RWN 2m & 70cm & 23cm (DV+DD) DSTAR repeaters, the WIA newslink Hub for VK6, the NCDXF International DX beacons on 14.100, 18.110, 21.150, 24.930 & 28.200. It’s WARG’s crown jewel hub site and has been given a very high priority for the initial stages of the network expansion and upgrades. No point in upgrading anything else if the core isn’t up to scratch!

Official Opening – D-Star Repeater VK6RWN – 18 October 2008

Hi All, Saturday, 18th of October 2008 is the DSTAR release presentation for VK6.

It will be held at the Darling Range RSL Hall, 35 Canning Road, Kalamunda, starting from 11.00am. (See map below for directions)

There will be a presentation from Icom representatives and then a practical demonstration.? They will also be available for questions and assistance so please make sure you bring your DSTAR radios along.

We will be having a sausage sizzle for lunch and John Tower will be there with some DSTAR equipment for sale!

Please come along, it will be good to see you all there.

Please pass this e-mail onto anyone that would be interested.

For further information please contact myself, VK6FZUK on 0414 533 244.

Regards, Danny Ainsworth – VK6FZUK.

googlemap

2M D-Star Duplexer

An update on the D-star 2M duplexer.

Having spent over 40 hours getting the D-star 2M duplexer ready has been a most interesting exercise.

The 6″ cavity filters we have had to be modified to allow them to work as notch filters and is bassed on the original design (4″ filters) by W1GAN JOHN J BILODEAU form an article in QST July 1972. What worked for the 4″ cavities had to be fiddled with on the 6″ ones.

The filters have been finished and now I’m fine tunning the coax lengths that connect the filters together. This part of the design was never covered well in the original or later articles. The lengths were given but not the reasons for the lengths. The lengths as given work but not as well as should be achievable.

The tracking spectrum analyser that WARG bought a while back has been fantastic in converting the 6″ cavities. Without it I could have tuned the duplexer up but would not have been able to do it easily and would not have been able to get results that can be achieved with the analyser.

The analyser shows you not just pass and notch but the type of curves. This has shown the interaction with the cable lengths that give various shapes, various peaks and dips that indicated the overall design is not working as well as it can and should.

With out the analyser the pass loss can be as high as 2.5 dB while with the analyster it can be as low as 1.5dB. Okay only a dB but it all adds up. The overall notch depth can not be seen on the analyser as it will not show 70dB plus notch depth. Each cavity can be seen okay but what happens when they are all connected together?

I can work this out using the analyser’s sig gen and a receiver and will do so next.

The attached photos show the PCB (painted) boxes on top and the difference with the pass frequency when you connect two cavities together with incorrect cable lengths. Each cavity has a good pandpass but when connected cause the bouble hump….Working on it.

Will
VK6UU

D-Star Update – 12 July 2008

We are expecting to be doing DSTAR repeater test transmissions within a fortnight. These will consist of 2m Digital Voice and Data, as well as 23cm high speed data. The repeater will only be active during certain periods throughout the weekends for the next couple of months.This is due to the expected delay with licensing from ACMA and could otherwise be fully operational 24/7 within the fortnight!

I would also like to start up a DSTAR simplex net if anyone is interested. If anyone would like to take part, or anyone in VK6 who has DSTAR capabilities, they can please email me VK3TWO/6.

I currently have gear capable of 2m, 70cm and 23cm and would like to make
use of them!

Thanks.

Heath – VK3TWO/6
VK6 DSTAR Coordinator