Recently I ran across an old article I wrote for BARC’s Bark (Boulder, Colorado, Amateur Radio Club) in November 1994. Some things have certainly changed since then, but much may still be of interest.
BARC’s BARK Volume 19 Number 11 November 1994
What’s the Fuss about QRP?
by Dave Casler, KE0OG
Every hobby has its fanatics. There are those who do technical climbing without equipment. People jump out of perfectly good airplanes. Wonderful paintings on pin heads. Bicycling in the snow. Two acre gardens. We hams have QRPers.
If you think DXers are passionate people, try listening to a group of QRPers! QRPers are devotees of the “less is more” philosophy. They rejoice in QSOs at ever lower power levels (soon one will figure out how work with negative power). They use terms like “thousands of miles per watt.” The smaller the transmitter the better— I’ve seen plans for a functioning transmitter contained inside a fountain pen!
What’s all the fuss about? Is there something here a sane person (like you and me) might enjoy? Is it just possible they may be on to something? Read on….
What’s QRP? QRP is the Q-signal meaning “Please reduce your transmitter power.” In more common usage, it means working with low-power transmitters. In the high frequency bands, it is generally accepted that QRP means working with five watts or less. That’s about the power used by your bathroom night light.
Why does anyone want to do this? First of all, working QRP is possible. The ordinary HF transceiver puts out around 100 watts, or around 20 times more than a five watt QRP rig. That seems like a lot. The difference between 5 watts and 100 watts is 13 dB. Well, 13 dB is only a tad more than two S-units. So a signal that is S-9 at 100 watts is S-7 at 5 watts. Normal fading (QSB) will make a signal vary more than that! Only under the most crowded band conditions will two S-units make much difference.
Second, five watts makes for zero interference with your neighbor’s TV set. You can operate anytime, anywhere with very little possibility of RFI.
Third, QRP creates much less band crowding. The real way to deal with crowded band conditions is not to increase power, but rather for everyone to decrease power to the minimum required to maintain communications. (And that’s what the FCC says we’re supposed to do anyway.)
Fourth, QRP transmitters require very little power. They do really well on batteries. This makes them portable (for camping trips, for example) and useful for emergencies.
And, fifth, it puts a bit of challenge back into ham radio. I still find it somehow magical that a signal from my back yard, literally using the same power as a large flashlight, can be heard and interpreted half a continent away.
Is it true that QRP is mostly CW? Yes, it is. Here’s why: Using CW, all of the transmitter power is concentrated on a single frequency. The signal can rise well above the noise. On SSB, however, the transmitter power is spread out over a 3 kHz bandwidth. The receiver now has to deal with 3 kHz worth of noise as well. It takes considerably more transmitter power to create the same signal to noise ratio (and thus the same intelligibility). Since every watt counts, most QRPers use CW. There are SSB QRPers, but they are vastly outnumbered by the CW QRPers.
Where is the QRP activity? Because of the low power, QRPers tend to use somewhat less active regions of the CW subband. Two very popular QRP bands are 30 meters and 40 meters. Look around 10106 and 7040 kHz. On 20, look around 14060, although PacTOR operations are putting the squeeze on this frequency. [Remember PacTOR? It’s still around, but not very much.]
Frankly, QRP is not for brand new HF operators. It’s like learning to ride a bicycle while your broken leg is still in a cast. Yes, it’s possible to ride a bike with a cast on. But it’s better to learn with all four limbs in working condition. So, start out with 100 watts, get the feel of HF operating, and then try QRP. You’ll find far less frustration this way.
What about equipment? There are three fundamental approaches: 1) Get/build a separate rig (transceiver) for QRP. MFJ makes a series of single-band QRP rigs that give good performance at a reasonable price (I have one). QRP rigs are simple to build and are commonly available as kits, or you can round up the parts yourself and build one from the plans in a book. 2) Build a QRP transmitter but use the receiver in your main HF rig. QRP transmitters are laughably simple. Often they’re just a single transistor and a crystal with a small number of other components. 3) Just turn down the power on your main HF rig. Kenwood and Icom rigs can go down to 10 watts or less. Yaesu rigs can sometimes go down to the milliwatt region. The books listed below have suggestions for getting the power down even further by using the ALC input on the back of your rig.
The other things to mention are feedline and the antenna. Every watt counts. If your old, water-logged feedline is cutting your power in half, that may be acceptable at 100 watts, but puts you in a real bind for QRP. Make sure your coax is less than three years old or so. Take your antenna apart, clean/buff all the aluminum connections and retighten. Clean and check all the coax connectors. Consider feeding a dipole with ladder line and an antenna tuner.
You might consider battery power for QRP. Eight D-cells in series will give you 12 volts, and can power a typical 5-watt QRP rig for a long time (most of the time you’re in receive mode, hardly using any power).
Are QRP operating techniques different? Fundamentally, no. You must be able to listen well, time your transmissions carefully, match your speed to that of the other station, and so on. The only real difference is that QRP operation is less forgiving, so your skill level needs to be higher. This is another reason to start your HF experience with 100 watts rather than five.
You’ll do best when band conditions are best. This means getting on the air often enough to be able to recognize band conditions—whether the band is open, how much static there is, how crowded the band is, and so on. Try early evenings on 40 meters, even earlier on 30, and even earlier on 20. Twenty meters can get very busy at times.
Calling CQ can be a problem. Many HF operators only answer clear, strong CQs. If your CQ sounds weak or watery, it may well go ignored. For this reason, most QRP operators wait for a CQ. I often put my MFJ-9040 on 7040 kHz [these days 7030 kHz] and busy myself with chores until I hear someone calling CQ. Very often those same operators who will only answer strong CQs are quite willing to work a very weak answer to their CQs. By the way, the next time you’re working 40 meter CW, try calling on 7040 . Chances are excellent you’ll be answered by a QRP station.
That’s not to say you shouldn’t call CQ. I’ve snagged a number of great contacts by calling CQ. Be sure to find a clear frequency in a popular part of the band (the first 25 KHz or so up from the top of the Extra Class portion of the band).
If there aren’t any CQs to answer, monitor a QSO in progress until it ends. Then call one of the stations. This is called tail-ending, and I’ve started many fine QSOs this way.
It’s a little known fact, but a fact nonetheless, that cutting your CW speed in half has the same effect as doubling your power. A weak signal at 10 words per minute is much easier to copy than a weak signal at 20 words per minute. For this reason, many QRP operators will use hand keys and slow down when conditions get bad. For the same reason, repeat critical information more than you might at 100 watts. Send the RST and your name three or four times instead of two. The other operator will love you.
What about contests? Many contests have a special entry classification for QRP stations, or QRP stations can get bonuses or multipliers. The reason for this is to encourage QRP operation.
There are special QRP organizations some of which publish newsletters. A local [to Denver] QRP group is the Colorado QRP Club, [current URL is www.cqc.org].
You operate QRP, don’t you? Ok, I’ll admit it. Yes, I do. But not exclusively. I have an MFJ-9040 singleband (40 meter) QRP rig [I also have 30-meter and 20-meter QRP rigs now]. Although not a true single-signal receiver and it drifts a bit, I’ve found it to be most satisfactory. It has an option for a built-in keyer and audio filter, and operates a long time on my homebrew 12-volt 2.5 aH battery/charger combination. I use a simple 40 meter dipole fed with ladder line and an antenna tuner. In the year or so I’ve had the rig, I’ve had dozens of CW QSOs. I use all the tips I’ve outlined above. Ill admit there are times it just feels better to fire up the Yaesu FT-747 [that was a long time ago!] and punch a 100-watt hole in the ionosphere! So I’m not a fanatic (really!). My MFJ-9040 puts out about 4 watts. Other rigs are available which have a continuously-variable power output.
I might point out that I’ve run my Yaesu at far less than full power. I’ve had recurring problems with RFI while running AMTOR. The solution is simple~I just crank the power down to maybe 10 or 20 watts. I can still connect to stations just fine.
One of my favorite QRP QSOs was with a station in Chicago. Band conditions were excellent, and his signal was a solid 599. He absolutely refused to believe I was using four watts of power, and said so several times! He said I sounded just as loud as everyone else.
One last note: I’ve found that QRP QSOs are not much more sensitive to the ravages of QSB and QRM than any other QSO. In other words, using QRP does not have that much effect on the quality of the QSO.
The experience of Eric Permut, KB0KQF [now KGØYS], is instructive. Eric obtained a used QRP rig as his first HF radio. Not truly QRP to the purists (it puts out 13 watts), he nonetheless has an impressive array of QSL cards to prove low power works.
Why is the ARRL pushing QRP so much? For quite a few reasons:
- It’s becoming a popular mode. There is a demand for articles and books.
- It improves operating skills—it’s more challenging than the mainstream 100-watt approach.
- It vastly reduces the amount of interference on our crowded HF bands. The League would like all of us to reduce power, for very good reason.
- QRP rigs are much less expensive than mainline HF rigs. It’s an inexpensive way for many to enjoy HF.
- The simple nature of QRP rigs encourages experimentation and construction projects.
Where can I find out more? There aren’t quite as many books on QRP as there are on antennas, but the gap is narrowing. Here are a couple:
Brad Wells, KR7L, Your QRP Operating Companion, American Radio Relay League, 1992. $6.00. A nice book, but not satisfyingly comprehensive. More of an appetite whetter. Lots of emphasis on contesting. Dave Ingram, K4TWJ, How to Get Started in QRP, National Amateur Radio Association, 1992. $11.95. Nicely comprehensive. Clear and understandable. Discusses commonly available equipment and kits. Suggestions for antennas and power supplies. Good discussion of operating techniques. Also discusses VHF/UHF QRP. I recommend this book. [Nowadays these are “really old books.” Although these books are still great, there are newer books out there.
Also see the October  QST, page 46, “What is QRP.” The article summarizes many of the same points made here, together with some additional information.
Ok, I’m ready! Great! 73s, de KEØOG.