It's so much fun to operate ham radio when your on about 50W of power. Unfortunately, the cost of a 50W, let alone a 100W transceiver, is astronomical. Luckily, there's a solution: QRP. The world of low-powered radio communication is full of endless possibilities. With activities such as POTA (Parks on the Air), SOTA (Summits on the Air, usually done from a mountaintop), or even QRP clubs, the world of less than 5 watts is limitless. Unfortunately, low power comes with the consequence of low power. Sometimes, you'll fruitlessly call CQ for an hour with no response, or you'll succumb to QRM, or really bad interference. But don't let that scare you away, as QRP can be really fun! It's all part of the challenge.
As a QRPer myself, I like to build radios, and that's where QRP becomes an art and a trade. QRP rigs are often simple to understand, comprising of at least two transistors. The infamous Pixie kit is a fine example of QRP. Simple to build and easy on the pocketbook, this small radio only outputs around 500mW up to a watt with only two transistors.
So how does one begin to operate a QRP station? In this post, I'll explain a few simple steps to get started.
1. Buy a rig or make your own
The first step to QRP operation is to purchase a QRP radio or build one yourself. A Google search will turn up many simple and interesting ideas to get you started. If you're looking to get on the air without assembly, consider buying a pre-made radio like the QRPLabs QCX transceiver. With only 5W of CW output and around a $50 price tag, it's a real bargain for the ham on a budget.
If $50 is still too much for your budget, you could always buy a Pixie or a Forty-9er kit. These are in the ballpark of anywhere from $5 to no higher than $20. Although they are rockbound, fitted with a direct conversion receiver, and they have a wide receive passband, simple modifications can be made to make the rig frequency-agile over a span of 2, 3 or even up to 100KHz in some cases.
2. Make an antenna
Next, you'll want to construct an antenna. The best design for any QRP rig is a 1/2 wave dipole for the band you want to operate on. To find the length in feet of your antenna, divide 468 by the frequency you want to use. For example, if I want to operate on 40m, say 7.050, I would take 468/7.050. This gives me an length of a little over 66 feet. For your antenna elements, I'd highly encourage 16 gauge speaker wire. This can easily be found on Amazon or in stores like RadioShack (If you still have one!) or even Walmart. Dipoles are super simple to construct, but if you operate on a band like 80m, chances are you're going to need some real estate and some space. Random wires also work, but aren't as effective for QRP operation.
3. Go portable!
QRP works best when you're in the field with plenty of space. Find a place with little to no obstructions, preferably a flat area or an elevated area. Here, you can set up your station and begin transmission. It also lets you get outside and enjoy the great outdoors. Who knows, you may even find the ideal spot to run any ops that you want for a future endeavor!
We QRPers and mobile operators make something called a go kit. It generally contains:
- Your rig
- Microphone/Key
- Your antenna assembly
- A computer, tablet, etc.
- Batteries, spare batteries, and/or a power supply
- Snacks and water
- Anything else that you find important to take into the field, like a notebook or your logbook
Portable ops are best when it's sunny to mostly clear out. Generally, operation happens in the daytime or early afternoon. Try to go out between the hours of 10:00am and 3:00pm, when activity is at its peak. Check websites like qrz.com for the latest solar and band conditions.
4. Configure your antenna setup
In step 2, I gave instructions on how to make a simple dipole antenna, although there are many choices when it comes to antenna construction. You can make verticals, random wires, inverted vees - the list goes on. When it comes to setting up your antenna, you need to make the area clear of obstructions, if you can do so legally and logically. Antennas require a lot of space, especially if you're operating on bands like 80m or 40m, where antenna lengths can get up to 100 feet. Make sure you have plenty of space to install your antenna. If you can, use what you have available to support your antenna, as long as it's legal and logical. Flagpoles and squid fishing poles work great for hoisting up and securing antennas.
As an option, you can also use a tuner if your antenna needs one. Many modern rigs have built-in ATUs and need no external tuning. With a press of a button, the antenna is tuned to minimum SWR. Some kits like the Pixie rely on good antenna practice and theory instead of using a tuner. Of course, if you really need a tuner or are comfortable using one, then take one with you.
5. Get to operating!
Now it's time to operate! QRP requires patience, so make sure you have plenty of time before you send out a CQ. It could be minutes or even hours before you get a response back. QRP is reliant on a quiet frequency, with little or no activity. Tune around the bands or change crystals if you encounter a busy frequency. 7.030, for example, is a good CW frequency for almost every ham operator. Unfortunately it is almost always busy with CW chatter because of this. Getting a Pixie to be heard on this frequency is almost impossible, and results are not much different with even 5W of power. Find a frequency that is quiet, and make sure that your rig is frequency-agile.
You've also got to consider what mode you are using. While SSB and phone is an easy task to accomplish, it won't get you very far on QRP. Modes like CW or FT8 will cut through and get out on the air much easier. The narrower the bandwidth, the better your results may be, and the more worthwhile your CQ calls will be. While I don't discourage the use of SSB on QRP, I feel that it won't be the best bet. You're better off using modes like CW, FT8, PSK31, and many other narrowband modes. As always, remember to be respectful and courteous while operating.
Personally, QRP is an interesting challenge, attempting to do more with less. It's fun, interesting, and personalized to your liking. You can build your own ham transceiver with parts that are commonly available, and simple equipment can be built and made without breaking the bank. I think that QRP is the heart and soul of ham radio because it gives each operator the chance to construct and operate his or her own piece of equipment. If you have a good knowledge of electronics, RF circuits and theory, chances are your QRP projects will be successful, and you'll likely make contacts with ease. That being said, QRP takes practice and patience, so don't expect a QSO on the first try. With persistence, QRP can be a fun and challenging way to keep homebrewing and amateur radio alive and well.
So what are you waiting for? The adventure of QRP awaits you!
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