Building an efficient HF station

Morse-code-operatorUpon discovering the Amateur radio hobby, I quickly realized what we’re the critical components needs to have an efficient HF station. In this case, bigger is not always better and here’s why. Radio waves are electromagnetic energy traveling thru space.

The name of the game is to transmit and receive this energy in the most efficient matter and after listening to countless hours of opinions given out by the most seasoned amateur radio operators and reading everything I could get my hands on, I came to the conclusion that most beginners think that bigger stations get the most signals. That is a false assumption.

To build an efficient HF station, you need to understand that the most critical components need to be considered, and in that order: location, antenna, transceiver and lastly, power. Each components will affect cumulatively how great your station will be, or how lousy it can become. Let look at them one by one in order of importance;

cultural-geographyLocation: there are many factors to consider when transmitting from a specific location; where you are in a given topographic area, where that area is in relation to other areas in your region and where on the planet this region is located.

An antenna on top of a hill will always be better than an antenna at the bottom of one, however, since HF waves use the ionosphere as a reflector, being stuck at the bottom of a valley will not prevent you from being able to do great radio contacts far far away. Being much higher than sea level also help with take of angles of your signals and helps it reach greater distances. Next come your terrain. The type of ground or soil your antenna is built on and the conductivity properties of it will definitely with your transmission. Humid or clay like soil are idea for your ground plane effect as opposed to sand or rock. You can always burry very long copper wires starting from your tower and run them in every directions, then ground them all to your tower (antenna). This counterpoise method will improve your signal and reduce noise. Also, don’t ignore or avoid installing proper grounds. This will help reduce RFI, reduce band noises and render your antenna more efficient.

Next comes the most important thing about your location and most of us can’t do nothing about improving it. Your geographic location of the planet will dictate how much you will benefit from HF propagation. See, Amateur radio operators living close to the equator have much more fun than those living near arctic circles. The closer to the equator you live, the better your signal should propagate. For example, in generals terms, two identical stations, one located in Northern Quebec, Canada, the other located in Florida USA, will have two very distinct performance reports, both in transmission and reception, and most of the time in favour of the Florida station. I am not suggesting you move to another country, but I often do envy Amateur radio operators live close to the equator. If you can’t move to a better location and have to live where you are, then you can improve your situation with the next most important component, your antenna.

antennaAntenna : Understanding how antenna works is important when selecting or building one. Resonating antennas will always outperform non-resonating antennas on any given frequencies and this is true both for reception and transmission. Even the most seasoned amateurs still debate performance of various antennas today. There are far too many types of antennas to recommend any of them in this articles.

Half-waves, quarter-waves, 5/8 waves, full-waves, directional, semi-directional, omni-directional, centre fed dipoles, off-center fed dipoles, folded dipoles, verticals antennas, horizontal antennas, inverted-v antennas, helical, yogi, spiral, loops, squares, bow, planar, log-periodics and just some of the type of antennas you might come across. You need to learn about them and figure out the type of application you want to use them for. Some antennas will offer best performances for short distance contacts as their take off angle will shoot your signal straight up in the ionosphere.

Others will offer spectacular results for long distance contacts as they will have low take off angles. This means that you need to learn about antenna properties, their signal patterns and lobes, their specifications for each bands and then decide what type of antenna you need for your specific application. Many beginners start with a multi-band dipole, place it in an inverted-v configuration and start from there. It’s a cheap way to begin learning about antennas, but if you begin to experiment with them, you will quickly realize how much more efficient some types of antennas are compared to others. Picking the right antenna is half the battle, the other half is setup. Placing your antenna at the correct hight, having proper direction and adequate grounding or poising, are as important as  selecting the antenna itself.

In conclusion, your antennas should represent the biggest investment (time and money) you should make. Knowing which band you want to operate on will help you make the right decision, but don’t be afraid to get opinions from others who have experimented a lot. You’d be amazed at the different opinions you will get from different operators about the same antenna. If you have space constraints, then you should consider operating on only the following HF bands: 80m for local, 40m for short DX and local, 20m for long DX.

pt8000_666Transceivers: You don’t need to spend a lot on a transceiver to enjoy the hobby, but selecting a sensitive and selective transceiver will help enjoy the hobby event more. From here, is it pointless to invest large sums of money into a transceivers if you are in a bad location and have a bad antenna.

Operators with envious locations and amazing antennas setup will have much more enjoyment form the hobby than if they’ve only invested in an expensive transceiver. I recommend you start small, a used basic HF rig, then work your way up. If you are new at this, you should not invest more than $300-$500 into an HF transceiver, then work your way up to the sub $2000 models and if you really enjoy the hobby, you could spend as much as $4000-$5000 into a rig. Spending more than $5000 is a  waste of money in my opinion, but if you have them means, go right ahead… indulge yourself! Also, remember that your transceiver is only the beginning… you might want to spend some money on better microphones, headsets, audio audio equalizers, antenna tuners, morse paddles and so on. Those extras won’t do much for your signal, but will improve your audio and make the hobby a bit more enjoyable.

In conclusion, all things being equal, a $250 used transceivers will probably give you the same performance and enjoyment as a new $3500 transceiver. Investing in your antenna system will real-in those weak signals and help you make more contacts. Most modern transceiver have similar sensitivity, the difference between a cheap and expensive ones will be the selectivity, the filtering components, features and capabilities and quality of parts used.

powerPower: most Amateur radio transceivers these days come with 100 watts of transmitting power. Most operators find it plentiful to enjoy the hobby, but their license might allow them to use more transmitting power, up to to multi-kilowatts of power in some countries.

However, it becomes pointless to use much power if you can’t hear the people you are listening to! We call this an alligator station (All mouth, no ears). Adding more power to your station can be challenging, costly and if not done properly, will create radio interference, might damage your investment and in some cases, burn to a crisp your antenna and coax system. Besides, the spirit of the hobby will convey you to always try to use  minimal amount of power necessary to establish communication.

Adding more power to your station can be as costly as purchasing a transceiver, but becomes totally pointless if you haven’t invested in a good antenna system. Other than a power amplifier, you will need a proper antenna tuner if you do not have perfectly resonant antennas. I would recommend you acquire about 5 years if experience using a 100 watts transceiver before considering adding more power to it. If you are operating at 100 watts and a station gives you a S3 signals, 200 watts would give you a S6 signal, 400 watts would give you S9 signal, 800 watts would give you S9+ 3db and so on. This quickly makes you realize that in most case, 500-600 watts of power if probably as much as anyone really needs. Also never forget that un-efficient antennas only transforms power into heat, not signal!

In conclusion, I hope you now understand now how important the balance between location, antenna, transceiver and power components are. Investing and experimenting with antennas is probably the most interesting aspect of amateur radio, and will also give you the most return on your investment. Enjoy the radio.


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