Blackdown Tablelands DSTAR repeater gets new hut
The DSTAR repeater at Blackdown Tableland has been relocated into a new site hut. This is a great waterproof home for all the gear plus room to spare. The VK4RBD DSTAR repeater is located at 940m above sea level and provides coverage to a large area between Rockhampton and Emerald in Central Queensland
147.6375MHz -600KHz VK4RBD C
Australia’s Highest DSTAR Repeater is now operational
439.300MHz -5MHz VK4RBM B
The Blue Mountain repeater site is without any doubt Central
Queensland’s best amateur radio repeater location. Surrounded by
thick tropical rainforest slopes and standing at 1040m, this truly is
a remarkable site.
Having such a picturesque, high elevation site does not come without other
challenges, the main one being access. The answer
is the help of a Jet Ranger helicopter and some superb piloting skills.
Once the weather cleared, we jumped into the chopper and cruised up to
the site. As we approached the site, the tower could be seen poking out above
the thick rainforest. The landing site is a small rocky area with
a tiny patch of grass. As we started to land, the view disappeared and we were
surrounded by trees, then we touched down, unloaded the gear, and the
We had a short time on site to install the new DSTAR,
APRS, 3G modem and solar regulator. The work was completed in
record time, and the chopper came and picked us up before the clouds
rolled back in.
Check out VK4RBM-3 on aprs.fi
The Blue Mountain DSTAR repeater is running on test, ready to be taken up to site. We are using APRS telemetry data to monitor and control the DSTAR repeater using the WX3in1 APRS modem. The analog inputs are being used to measure:
- Battery voltage
- Transmitter cooling fan current
- Raspberry Pi and DVRPTRv1 current
- DSTAR transmitter temperature.
(see VK4RBM-3 on aprs.fi)
The fan current and transmitter temperature is particularly handy as it shows equipment utilisation. When the repeater is active with users talking on it, the transmitter temperature rises, so the fan cycles in. Another benefit of monitoring the temperature on the transmitter is that a sudden spike in temperature will indicate a fan failure. Our design includes two fans, a main and backup that are both temperature controlled. These fans can be turned on and off independently.
The wxbits output module is being used to control some repeater functions. The repeater transmitter can be disabled using the transmit inhibit function. The repeater output power can also be controlled. The transmitter radio channel table has two channels programmed in; one at 25 watts and the other at 5 watts. The wxbits output module allows the radio transmitter channel to be changed remotely between high and low power. The low power channel uses less current than the high power channel. This is handy when the site battery level falls because you can keep the site operational for longer by changing the transmitter to low output power.
We have also included a selcall activated relay. The 12V bus that supplies the Raspberry Pi is fed via the relay in its relaxed state. When a selcall is sent to the transmit radio the relay is energised, disconnecting the 12V bus for 5 seconds. This feature is used to remotely power cycle the Raspberry Pi in the event that it locks up and becomes unresponsive.
A 3G modem is being used to provide internet access for the Raspberry Pi. The 3G modem has serial ports. These serial ports have been setup to provide a serial tunnel so that we can monitor and control the Plasmatronics solar regulator. The advantage here is that we can closely monitor the solar and battery condition. This also provides yet another method to hard reset the equipment as the load control from the solar regulator can be controlled remotely.
The 3G modem also provides additional functionality using its controllable dry contacts. Each piece of equipment can be individually turned on and off using text messages or the web interface. The benefit of this is that it provides an additional tertiary power cycling feature, should a hard reset of the Raspberry Pi or APRS modem be required. It also allows enabling either the main or backup fan.
As you may be aware our VK4RBY Black Mountain site was broken into a few months back and some gear was stolen. We are now backup and running on DCS028Q with a 70cm DSTAR repeater. Work is underway to install a 2m multimode repeater at this site in the coming months. Historic data usage shows we use about 1.5GB per month. We are testing a prepaid Optus simcard to provide internet access. The Optus deal is good value, $130 for 22GB with a 2 year expiry.
The north west coast of Tasmania is set to receive D-Star in the coming weeks. Aaron, VK7AGR has an Icom 70cm repeater and G2/3 gateway on test and is destined for Installation at Table Cape in the town of Wynyard. Final preparations are underway consisting of antennas and a 5.8GHz link to provide NBN internet to the gateway.
The repeaters callsign is VK7RAC and is licensed to operate on 438.700MHz, -7MHz split. This repeater will be a welcome addition to Tasmania’s D-Star repeaters with VK7RCR in the Lenah Valley serving the south and VK7RAC serving the North, as well as connecting Tasmania to the mainland and the World Wide D-Star community.
News from Clayton Reading VK7ZCR.
Last month’s Miena Hamfest in the Central Highlands of Tasmania was a great success. Clayton setup a D-Star table and the interest was solid all day. 150 Keen Amateur Radio Operators attended the hamfest. Clayton was assisted by Ken Sulman VK7DY. They had D-Star on air via a DVAP system, They had equipment on show and played D-Star information Videos for eager customers. Well Done guys !
P.S. Clayton is the admin of VK7RCR, a D-Star repeater that runs near Hobart in the Lenah Valley