Another properly timed business trip to Oklahoma gave me the opportunity to camp out in my favorite part of the state at the best time of the year and participate in QRP to the Field. A $2 permit, a KX1 with all the fixin’s & a pack to haul it in and you can color me “There”!
The night preceeding the event brought heavy thunderstorms and an uncertain prediction from that weatherman all you
Oklahomans love, Gary England. Talk to me, Gary – tell me it’s gonna be okay! But Gary wasn’t talking with any certainty so I put my laptop’s media player in the “loop” mode and played CCR’s “Who’ll Stop the Rain” over and over to supplement my prayers for clear skies. It worked.
For a long time now, I’ve enjoyed taking QRP rigs outdoors and operating from a variety of locations. I’ve always powered them with AA alkaline batteries but this time I wanted to try something different. A few months ago, Gil Stacy NN4CW and I exchanged several emails on his ATS-3 and the Spartan Sprint contests. In an effort to shave weight, Gil was using rechargeable Lithium-Polymer batteries. I didn’t know anything about them at the time but was about to learn for another reason: another friend is starting to get interested in electric R/C airplanes and has gotten me infected with the bug as well. Just what I need – another hobby. Anyway, to make a long story just a bit longer, I’ve learned that these LiPos pack a lot of capacity into an extremely lightweight package. They have a high initial cost and require a dedicated charger but they are capable of high current discharge and weigh next to nothing.
The battery I used for the QRPTTF weighs just under 6 ounces and provides 12V at 2700 mAh. That same capacity using AA batteries weighs 12 ounces, requires a holder and the voltage decreases (causing a corresponding RF output decrease) beginning with the first QSO. With my LiPo battery, I started the TTF event with at 12.1 volts (key up) and ended 28 QSOs + 2 ragchews at 12.0 volts key up. The difference between transmit and receive voltage was 200 mV and stayed that way for the duration. With alkaline AA’s, the difference is greater and steadily increase to over 1.5 volts difference after an hour (typically) of contest-type operation.
The photo shows the three LiPos I have, with the KX1 for size comparison. All three batteries are 12 volts: the top-left battery is 450 mAh and weighs 37 grams. Next to it is a 950 mAh weighing 60 grams. Also shown is the pigtail that connects the KX1 to the battery’s JST connector. I have used the 450 mAh battery with my KX1 at 2 watts output for a solid hour during an NAQCC sprint with only .3 volts drop in voltage over that time period.
The only difference between this campout and last year’s is that I left the Whiterook paddles at home and brought the KX1′s plug-in paddles instead. This eliminated an extra cord – and that’s a good thing, as Martha would say. Does anyone know if a Tupperware container exists whose dimensions exactly fit that of the KX1? I’d love to be able to carry the rig in such a way that the knobs and antenna jack are protected without having to add packing material in a too-big sized box…
I love my ATS-3 but when it comes to convenience and get-on-the-airability, nothing beats the KX1. This is primarily due to the built-in autotuner which was able to tune my 40m dipole (twinlead fed) in mere seconds on all three bands with 1.3:1 SWR or less.
On the Air From the Wichita Mountains
What can I say about this beautiful place that I haven’t already said? It amazes me everytime I go there and I think it’s Oklahoma’s best kept secret. During the contest, Ted AA5CK told me that it’s his favorite spot in the state and I wholeheartedly agree. Like last time, I had the place to myself and the weather was great – cool and sunny. Buffalo were everywhere and sunset was punctuated by howling coyotes. I thought I’d hear them all night but that was it – I guess they were off to other doin’s.
By the time my tent was set up and the dipole was ready to burn a hole in the ether, it was 1840Z. My first contact was at 1844Z on 20 meters with K7TQ in Idaho who was booming in like a beacon all afternoon! For another few hours on 20m, I alternated between “search & pounce” and calling CQ. Just before I switched to 40 meters, LZ4UU called and gave me a report from Bulgaria. I only operated on 40m for an hour, starting with John N0EVH who was mobile up in Missouri.
In all, I made 25 contacts then had several QSOs after the contest. It was a great time and I wish I’d been able to dedicate more time to it but I also wanted to hike around the Refuge and plan my next trip which would involve camping way up on a peak. I tried to find one within my abilities and expended a lot of effort and sweat in the process. Climbing these peaks is really more “boulder scrambling” than climbing. I also need to come up with an antenna that doesn’t rely on trees since the top of all these peaks are flat rock. Time to re-visit the St. Louis Vertical or something similar…