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Operating QRP can be challenging enough. Operating portable QRP can be even more of a challenge. But, with the proper equipment, like a good matched resonant antenna, you would be surprised with the results.
One thing nice about QRP rigs is, they are usually much less expensive than rigs in the 100 watt category. That’s not to say that you can not turn the power down on your top of the line 100 watt rig to be in the QRP category. There are a lot of very reasonably priced, very good quality, rigs that can be purchase brand new for a price that won't break the bank.
Complete Compact QRP Station
The Icom IC 703 Plus with the 500 hz CW filter makes a great little portable QRP rig. I went into the setup menu for my 703 and set the maximum output power at 5 watts. The battery pack for the radio is wire tied to the right hand side of the radio. Everything shown on the table will fit in the VHS camera bag shown to the left of the rig. I paid $10 for it, brand new, at a local flea market.
With this setup I worked Florida and into the Czech Republic from the picnic table in my back yard using the little vertical antenna attached to the back of the radio. I live 100 feet below average terrain. This is not an ideal location for working DX. You will have a hard time working the world with this little setup, but if the bands are in good shape you should be able to work some DX with it. If you connect a simple dipole to the 703, there is no reason you could not get DXCC with it.
They no longer manufacture the IC 703 Plus and that's a great loss.
Here is the needed information if you would like to make your own radio mounted vertical antenna.
Magnetic Loop 15 to 40 meters
The magnetic loop is a very efficient antenna. I watched some videos on, "YouTube" about them and also did some other research. Shown on the right is my 4 foot diameter loop that can handle up to 70 watts. When running that amount of power to the loop you are sitting next to a concentrated RF field and is over the limits allowed by the FCC. The small coupling loop on the inside bottom of the big loop is connected to the coax cable. You should use an RF choke at that point. The coupling loop is 1/5 th the diameter of the large loop. By moving the little loop up and down on the mast you can lower the SWR. It should be kept close the bottom of the mast. The capacitor that is on the loop, shown in the picture, is rated 5 KV and its range is 12 to 100 pf. It will allow me to operate from 15 to 30 meters. To operate on 40 meters I have to shunt a 50 pf door knob cap across the air variable. I’ve since changed the capacitor to a dual section air variable rated at 800 volts and is 12 to 460 pf per section. I wired the two sections in series. The value is now 1600 volts and the range is 6 to 230 pf. This will allow me to operate from 12 meters to 40 meters. Maximum power is limited to 20 watts. 20 watts is a one S unit gain over 5 watts. This antenna has a very high Q.
A friend of mine and I made an interesting test. He set his up on a table no more than 10 feet away from me. He was on 40 SSB with his magnetic loop and I was on 40 CW with my magnetic loop. We both ran only 5 watts and, without band pass filters added and we did not interfere with one another. My friend was using his K3 and I was using my IC 703 Plus.
The two above pictures focus on table top antennas. They are fun to use but there is nothing like a resonant wire antenna strung in the trees. If trees or other tie points are available so I can erect a wire antenna, I do so. I always take three different coaxial fed antennas with me. One of the antennas is a dual band, "model 2B2040LQ" , that covers 20 and 40 meters. The overall length of that antenna is 44 feet. It can handle up to 150 watts. The next antenna, and usually it is the first choice to erect, is the 40 meter Off Center Fed antenna, "model OCF40Q". This antenna will cover 6, 10, 20 and 40 meters. It is rated at 250 watts. If room permits, I will erect the third choice which is the 80 meter Off Center Fed antenna, "model OCF80Q" This model will cover 6, 10, 12, 17, 20, 40 and 80 meters. All of the above antennas are made by, "Hy Power Antenna Company." The dual band uses a 1 to 1 current balun and the OCF’s both us a 250 watt 4 to1 Guanella Current Balun.
Starting in the year 2020, I added a 40 meter half wave end fed to the mix. This is a home brew antenna that uses a 64 to 1 UnUn at the feed point. I feed this antenna with 25 feet of RG 174. A 50 ohm line isolator is place, on this coax, 25 feet away from the UnUn. Remember, without a counterpoise, the coax becomes the second part of the antenna and will radiate. A line isolator must be installed or you will have RFI issues at the radio.
You Kits / Ten Tec R4020 QRP / 5 Watts
This is a fun little two band ( 20 and 40 meter) radio made by You Kits in China and sold through Ten Tec. The radio is rated at 5 watts output power when supplied with 12 volts. Eight batteries are installed inside of the rig. If you use Nickel Metal batteries the supplied voltage will be much lower than 12 volts and the little rig will only put out about 2.5 watts. I found a set of Nickel Zinc batteries on Amazon and are made by PowerGenix. These batteries, once fully changed, will produce 1.6 volts @ 2500 mwh. You must use their charger. I purchased 16 batteries and two chargers. These batteries hold a shelf charge much longer than the Nickel Metal batteries. With these batteries I get the full 5 watts output power.
Ten Tec is no longer selling the You Kit radios. Vibroples is now selling a four band version of this radio.
It covers, "15, 20, 30 and 40 meters". The newer versions of the You Kit radios come with an internal battery and can be charged without removing the battery from the radio.
If you would like to get a feel of how my OCF40Q works with a radio, watch the video shown on the left. I don't use a tuner and don't need a tuner. I found the OCF40Q to be a great antenna to use when setting up portable. I never use a tuner and work numerous bands. One antenna, one coax, no tuner, no antenna switch and work numerous bands. What more could you ask for?
When operating portable with the FT-897D, I always cut back on the power output to only 50 watts. This saves on current drain on the battery and is only 3 DB down from 100 watts. That means that the receive end of my signal is only 1/2 of an S unit down from when I would transmit at 100 watts. So instead of the receiver seeing an S 9 with my 100 watts, it would see an S 8-1/2 with my 50 watts out of the radio.
This picture shows the OCF40Q made by, "Hy Power Antenna Company" , erected at the local park I enjoy operating from. The average height of the antenna is 35 feet. One end is tied to a tree and you can see the other end tied to the back stop of the baseball field. Most of my portable antennas are fed with RG 8X. For very short cable runs, 25 feet or less, I've been using RG-174.
MFJ 9020 QRP / 5 Watt CW Radio
Here is an economical little package that can get you on the air with some spare change. This is the MFJ 9020 QRP / CW rig. This one has the optional CW keyer and audio filter built in. You can usually pick these up used for between $85 and $125. You do not have to use CW paddles to key the rig, a straight key will do. The battery is a 7 ah Gel Cell that sells new for around $20. When I take this little rig portable I usually us a 12 foot long 20 meter dipole, model LD2012Q made by Hy Power Antenna Company.. I have since sold my MFJ 9040 and 9020 and I purchased the KX3. I really enjoyed using these little rig.
They do make a SSB version of this rig and you can even install the optional CW board in it. This would give you the best of both worlds, SSB and CW. The model number is MFJ 9420, good for 10 watts out and has a great RF speech processor. This model usually sells used for $150 on up.
Begali Magnetic Traveler Light paddles are shown in this picture. I love these paddles, they are a, "Work of Art !" I now have three sets of these paddles. One set in my car, one set in the shack and the third set I use when I operate portable.
W3CE's FT-817ND "Go Kit"
This great little setup is owned by Al, W3CE. Everything you see on the table, including the antenna, will fit in this, "Go Kit."
The package consists of an FT-817, Tokoyo Hy Power 50 watt solid state amp, LDG antenna tuner, CW paddles with memory keyer, hand mic, speaker and gel cell battery.
The antenna is stored within a compartment inside of the lid of the go kit.
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