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Operating portable can be a lot of fun. You don't need a massive tower and yagi array to work the world. A simple wire antenna and a small rig is all you really need. My favorite high power rig for portable operating is the Yaesu FT-897D, now upgraded to an FT991A. For a rig in the 100 watt category, it draws fairly low current compared to other rigs like the Yaesu FT-450 and the Icom IC 7000. With less current drain on you battery, you will be able operate a lot longer before the battery goes to a low voltage state where the rig will no longer operate correctly.
I published a product review of the Yaesu FT 897D in the local club's newsletter. Here is the article: FT 897D product review PDF. There is a rig current drain comparison chart in this review.
I found operating at one of the local parks, on top of a mountain, to be a lot of fun. I've used numerous antennas ranging from a simple table top home brew antenna to numerous antennas made by Hy Power Antenna Company.
Complete compact portable 100 watt station:
Shown to the left is my FT 897D w/500 hz CW filter. I mostly operate CW but at times, if the band is in good shape, I will operate SSB. When operating portable I will either run 5 or 50 watts. The battery can handle short operating times of 100 watts but that limits the amount of time I can stay on the air. Remember, 50 watts out is only 3 DB down in power from 100 watts. That comes out to only ½ of an S unit less in signal strength. I judge my power level on band conditions.
The day this picture was taken I was using an Off Center Fed antenna (OCF40Q) made by, "Hy Power Antenna Company" . This antenna will cover 6, 10, 20 and 40 meters. It is their low power version that is rated at 250 watts. The Kenwood TH F6A is to the left of the rig and I listen to the local repeater while I’m at the park. I can’t hit the repeater from that location with the HT but the repeater has a 6 meter input. If I want to talk to anybody on the repeater I just put the 897 on 6 meters and with 50 watts to the "OCF40Q." I am then full quieting into the repeater. In the second picture shown to the left are SWR readings of the OCF40. Take note how low the SWR is per band. An ATU is not needed when using this antenna.
If there is enough room, I will erect the OCF80Q . This Off Center Fed antenna will work on 6, 10, 12, 17, 20, 40 and 80 meters. The overall length of this antenna is 135 feet.
Hy Power Antenna Company also makes Micro Series dipoles and OCF's. These guys will fit in you pants pocket. A full size OCF40QM is an off center fed 40 meter antenna that works on 2, 6, 10, 20 and 40 meters. It will handle up to 250 watts and fits in your pants pocket.
To the left the Rig Expert antenna analyzer shows the SWR on a given frequency on each band the OCF40Q works on.
Table Top Vertical Antenna with ground radials:
The photo to the right shows another idea for operating when there are no tie points to erect a wire antenna. This is a home brew table top vertical. The mast is made by Hustler and is the 22 inch long mobile mast. I picked up a B&W high Q coil at a hamfest for a few dollars. I use a short jumper to change bands. With the telescopic whip and a few ground radials I am able to operate from 10 to 40 meters. The antenna can be broken down and carried along with the rest of the equipment. The efficiency is down from a simple dipole but you can work DX with this setup if the band is in favorable condition.The antenna will easily handle up to 100 watts and more. The performance can be enhanced by adding more ground radials.
Here's the needed information for building your own clamp on table top vertical.
In this You Tube video I make reference to the vertical mounted on the back of the IC 703. What I am talking about is shown in the picture on top of my QRP Portable web page.
Time for a little comfort, out of the weather.
Sometimes it's fun just to get out of the shack and set up portable in back of the van. The radio is a Yaesu FT991A operating at 50 watts. Remember, 50 watts out is only 3 db down from 100 watts and on most radios that equates to one half of an S unit lower in signal strength. It also saves some current drain on the battery. This will equate to a longer operating time before the battery is depleted. My logging software is, "Log4om." I also use my phone's hotspot so a can not only get callouts from the cluster but check the spots for working, "Parks on the Air" hams.
The antenna is 14 feet 6 inches long. The mast is made out of 1 inch copper tubing covered with shrink tubing. The coil uses a very high Q design. It is also tapped for 20 and 40 meters.
Two band (20/40) wire vertical antenna.
The telescopic fiberglass mast mounted on the back of the van is 28 feet tall. A dual band, 20 and 40 meter, wire vertical antenna is mounted to the mast. The total length of the wire vertical is 23 feet. A 1 to 1 Guanella current balun is at the feed point of the antenna and the van is the counterpoise. It is less than 1.5 to 1 across the entire band on 20 meters and has a 2 to 1 bandwidth of 210 khz on 40 meters with its resonant frequency set at 7080 khz. The antenna can easily handle up to 250 watts if needed.
The mount for the fiberglass mast is a short length of 3" PVC bolted to an steel angle that is attached to the exposed hinges for the rear door. The steel angle is also the mount for the mobile antenna when used.
This mast is very rigid and the top section does not bend like the ones sold by numerous ham dealers. It's an actual telescopic flag pole. This can be purchased at the following site: 28 Foot mast
I did not want to be locked into using only the van when it comes to setting up the 28 foot mast. I had some extra wood laying around and came up with the following idea. I used only wood screws to assemble and mount.
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