From VK5SW in the Outback of
The advent of the
Internet has changed our lives. It
has definitely impacted the hobby of
Amateur Radio. For me, the prospect of setting up a
remote station seemed rather daunting
at first but I soon came to
realize that it wasn't that
Remote operating basically consists of two or more computers connected together via the Internet with the remote computer also connected to the ham radio station. With suitable software installed in both computers, the control computer is able to operate the remote radio via the remote computer. There are variations to this. The software used here is Ham Radio Deluxe running the DM780 program on BPSK31. At this stage, this is the only mode I use while remotely operating the station.
Solar Powered Remote Ham Radio Station Equipment
The remote computer is connected to the Internet using a wireless connection:
as the available Internet server antenna is ten kilometres, (about 6 miles) away. Luckily my brother inlaw Greg owns the property next to ours. So when I am at the home QTH which is about 150 kilometres (aprox 93 miles) away and he is at the property, he is able to turn on the remote computer and radio and connect to the Internet for me. Once Greg has told me the IP address of the remote computer via mobile phone, I am able to connect to it and operate the remote station from the home QTH. The distance between computers doesn't really matter. If the Internet connections of both computers are hard wired, then you wont need the assistance like I do to operate a remote station.
The home QTH is in
Adelaide, South Australia (VK5) which is
about 150 kilometres away from the
The home computer setup in Adelaide
where I operate the remote station in the Outback using BPSK31.
To actually control the radio from a distance is a great experience.
The background noise level on the radio at this remote location is strength zero.
So if you have worked me while operating the remote radio, this is the station configuration used.
If you would like to set up a remote Ham Radio station, I recommend that you purchase a copy of the ARRL's 'Remote Operating for Amateur Radio'.
The Solar Powered Side of the Station:
Since I wrote this article I have been told that deep cycle batteries can be discharged regularly by 50%... Wikipedia agrees with this... So, I telephoned the company again that I bought the battery from and was told that they recommend 20% to increase the life of the battery... Therefore, regular discharge of deep cycle batteries of 50% or less is ok...
There's an interest nowadays in alternative forms of power but the most popular for Amateur Radio Operators would have to be Solar Power...
Although I don't know much about solar systems, I can share with you what I do know...
There are basically
3 components to a Solar
1. The Battery,
as seen on the floor left side of the station equipment
2. The Solar Panel and 3. The Controller
The controller on the right photo above is used to regulate the current going into the battery from the solar panel shown on the left...
The sizes of these depend on the amount of current you need to draw from the battery and the duration... Once you work out these 2 requirements, you're able to figure out the capacities of the 3 components... In my case for example, I operate CW on HF so the current draw on the battery would be about 20 Amps... For a 100 watt radio, using Ohm's Law, you would expect the current drawn using a 12 volt supply to be about 8 amps or so. ( 100W = 12V x 8.3A ) but because most modern solid state radios are only about 50 or 60% efficient on CW and a little more efficient on SSB, the current drawn is nearly double that... That's why most 100 watt radios which have 13.8 volt dc power supplies are rated at around about 20 amps...
So, if the transmitter was run for 1 hour, it would mean that the battery has used 20 Amp Hours in that period... Batteries are rated in terms of their voltage and the number of Amp Hours that they can supply... However, batteries used with solar panels need to be of the 'Deep Cycle' type... They should only be discharged up to about 20% of their capacity to extend their lifespan... If, for example, you have a 100 Amp Hour battery, it shouldn't be discharged by more than 20%. ie 20 Amp Hours so that 80 Amp Hours of the battery's capacity should still be available...
The battery I use has a rating of 670 Amp Hours... 20% of that is approximately 130 Amp Hours... Therefore, if the transmitter was to run for 6 and a half hours at 20 Amps, the battery would be down to the allowable ' discharge level '... There are many different types of batteries available nowadays but I bought a lead acid type made by Exide in the USA because it's a proven and reliable type of battery, old technology... It consists of 2 volt cells in series to form 6 volt batteries, 2 of which make up the 12 volt supply... A battery this size can power a small house but you would need a number of panels to recharge the battery quickly due to the regular current drain by house hold appliances etc... They're not cheap... This one cost $1500 Australian a few years ago and the expected life is 10 years or more if looked after properly... ie distilled water topped up... The voltage at the battery fluctuates with the current coming into it from the panel... It may swing from 12 volts or so of a night to 14.5 volts or so in the daytime... I have 3 different radios that I've used with this battery and the voltage swing doesn't seem to affect them...
The amount of charge going into the battery is dependent on the size of the panel, it's direction towards the Sun and the availability of sunshine... Since we're not at the Radio QTH all the time and drawing current, the battery doesn't need to be charged quickly on a regular basis... One 80 watt panel is sufficient for my needs ie. to keep it charged... It's made by BP and at the time cost nearly $700 Aust... The direction that the panel faces is important to maximise the exposure to the Sun... Also, the angle to the horizon should be optimized to ensure that the Sun hits the panel as near as perpendicular as possible throughout the year, especially in the winter... High tech panel installations track the Sun...
The ' Charge Controller ' or ' Regulator ' ensures that the right amount of current from the panel is fed to the battery... When there is a large current drain from the battery, the regulator will allow maximum current to flow into the battery from the solar panel... With the panel shown, a maximum current of nearly 5 Amps can be produced with a cloudless sky... When the battery is nearly fully charged, only a small amount of current is sent to it... The maximum Amp Hours this panel can manage at this QTH seems to be about 35 AH or so a day ... When buying the battery and panel, the sales people will sell you the appropriate controller as well... The solar controller like the one shown in the photo above with an LCD screen is able to tell you a lot of information... eg. the voltage at the battery terminals at present, the amount of current going into the battery at the moment, the number of Amp Hours already gone into the battery so far today, the total Amp Hours sent to the battery each day etc...
The other consideration is the wires connecting components... To reduce voltage drop, ensure that you use heavy gauge wires and also use fuses in the main lines... Ask the sales people questions, they want your business...
And all of this is used to get the rig on the air shown in the picture below!
The Solar Powered Yaesu FT-897
VK5SW Using the Icom IC-7600 on Solar Power
Screen shot from video below