VK4GED RMS on HF bands in Queensland, Australia

Our monoband RMS is usually on the 40 metre band, on the same frequency as VK4DJC's RMS on 7050.5 kHz dial. With 380 kilometres between us, select whichever station gives you best access to Winlink email.

Antenna-wise we use a compact horizontal dipole on a first floor balcony. The dipole is made up of two back-to-back Shark Hamstick mobile whips fed with 50-ohm coax cable, no balun. Sandwiched between a sloping steel roof and balcony railing, the setup works remarkably well. The NNW/SSE radiation pattern suits the closest radioamateur population along the east coast of northern Australia. When contacting stations in southern states, we can turn the dipole 20 degrees to favour their direction.

Sometimes the 40 metre dipole comprises one standard length whip and one Shark mini (shorter) whip. The mini version fits easier on our balcony amongst the outdoor furniture. There might be about an S-point difference between the standard and mini versions. Having three mobile whips on 40 metres gives the capability for Winlink HF portable.

On request, to check propagation with your station, we can mount mobile whips on top of a 4.5m telescopic vertical pole, providing omnidirectional Winlink signals on the 80, 40, 30, 20, 12 or 10 metre bands. On days when we're not on 40 metres, we tend to be on either 80 metres or 30 metres to keep coverage reasonably local.

Our RMS's transmitter is a Xiegu G90 outputting 20 watts. An external fan runs continuously to keep it cool, important during long Winlink QSOs. Due to QRM from overseas at night particularly on 40 metres, the receiver preamp is on during daylight hours and off at night, the AGC is set to Fast to recover quickly from static crashes, and the squelch is off. We use VFO-A for voice, and VFO-B for Winlink (noting that all settings for digital comms are retained in the VFO), making it easy to flip back and forth between modes.

The audio interface is a SignaLink USB box connected to a DreamQuest miniPC running RMS Trimode software on Windows 11. We might be changing the interface to a Xiegu CE-19 so we can use the SignaLink unit with a different transceiver.

The RMS settings are:
. Mode = VaraHF only.
. Session Timeout = 45 minutes, although unregistered VARA connections are limited to 30 minutes.
. Maximum Daily Usage = 150 minutes.
. Wide channel bandwidth = 2750 Hz, with 500 Hz connections accepted.
. Morse ID = on.
. Service Codes = PUBLIC EMCOMM WICEN VK4WICEN.
. Availability = H24, except when testing or for voice transmission nets*; before calling, please check our current VARA frequency on https://winlink.org/RMSChannels .

*Parallel voice and Winlink HF nets:
Once a week (on UTC Saturday from 2200Z) our RMS is used for Winlink check-in messages at the same time as the 'VK4 WICEN' SSB voice nets are conducted on HF. Schedules and frequencies are on the VK4 WICEN/EmComms page at https://groups.io/g/vk4-emcomms .

Hope to see you in the RMS logs. 73 de VK4GED