Making a telephone call with a Barrett 940 HF radio on the AusTravel Safety Net from Binghi Station

Описание: Making a telephone call via HF radio in the Australian bush on 5127 Khz USB (VMD750 AusTravel Safety Net Channel 2).

We were camping deep in the Australian bush on 4,000 Acres of private property in Northern New South Wales for four days and had ZERO mobile telephone coverage the entire time. Thanks to our AusTravel Safety Net subscription, we could make telephone calls to family and friends with our portable HF radio.

Apart from driving 2.5 hours to get to the nearest town (Tenterfield), the only other way we had of contacting the outside world was by HF radio (shortwave radio). We could use the HF radio to talk to other HF radio operators all over Australia OR we could also use the HF radio to make telephone calls to landlines and cellular mobile telephones.

Being able to make a "telephone call" from somewhere without mobile phone coverage gave us a "lifeline" in case of emergencies, a way to keep in touch with loved ones and as we also found out, a way for us to catch up on the latest COVID19 pandemic news (like 12 million Australians being forced into full lock down and face masks being mandatory in all public places whilst we were away!).

The HF shortwave radio we used was an Australian made Barrett 940 portable radio (ex Australian Defence Force radio in man-pack configuration). It had a TX output power of 30 watts and was capable of operating in AM / LSB / USB from 2 Mhz to 30 Mhz.

Since we were setting up the radio for base-camp use, instead of using the 5m collapsible vertical whip antenna, we opted to string up a simple end-fed longwire antenna at a low angle for NVIS operation (so low that part of the wire antenna draped over a huge boulder - another section was also wrapped around a tree). The low angle of the wire antenna gave us a better chance of connecting to the nearest HF radio base which was at Casino in Northern New South Wales.

We subscribe to the AusTravel Safety Net (callsign VMD750) which means we can use our commercially manufactured HF radios to make voice calls to landlines or cellular mobile telephones connected to a regular telephone network.

This works by dialling the radio base number that gives you the best radio signal strength (in this case 2199 - Casino Base), then you simply dial the telephone number you wish to call. The remote radio base (Casino Base) has a HF radio / telephone interface which connects the two systems together. Once it identifies your attempt to call, it will connect the HF radio to the telephone network and dial the number for you.

When using this system, things are a little different for the person you are calling on the other end of telephone. Firstly, because their telephone is "connected" to a HF shortwave radio, they will hear static or white noise which is normal. They may also hear interference from lighting (audible lightning crashes) from far away electrical storms, and on the odd occasion they may hear other faint voices on the frequency.

On the radio users end, just like a UHF CB radio, when you press the Push To Talk button on the microphone it cuts out the radio speaker so unlike a normal telephone, only one person can speak at a time (otherwise you won't hear each other). Because of this, it's a good idea for both the radio operator and the person on the telephone to both say "over" each time they are finished speaking so the other knows it's their turn to talk. Yes, it's a little weird for the person on the telephone end to say "over" but If they don't, the person on the radio might start talking over the top of them and not hear what they have to say.

Whilst HF RadTel is old technology, it can still work very well......especially when you have no other means of contact! AusTravel Safety Net offers an excellent package at a low cost (around $100 for an annual subscription) that also includes the ability to send SMS messages from HF radio to mobile telephone, send GPS location from HF Radio, their easy to use HELP function for emergencies and a whole lot more.

Check them out at

https://www.austravelsafetynet.org.au/