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      • Magnet Loop >
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        • Vertical Antennas >
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            • DIY 40m -10m Short Vertical Antenna
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          • 1/4 wavel 20 meter Veritcal >
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            • Make a KW4JM vertical
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        • Other Portable Antenna Options
      • Dipoles/Inverted VEEs >
        • Off Center Fed Dipole OCD
        • Comparing the Trap vs. Fan Inverted Vee
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        • Trap Antennas >
          • 20 & 40 meter trap dipole qrpkits
          • 40/20 Meter Trap-Inverted Vee
          • 17/20/30/40 Trap Inverted Vee
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        • G5RV
      • Base Station and General Antennas >
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    • Portable HF.... >
      • Pedestrian Mobile >
        • Ped Mobile Considerations
      • POTA - Parks On The Air >
        • Thots on POTA Activations
        • My Ideal POTA Kit
        • POTA - Lizard Mound State Park k-9704
        • POTA k-3383 Bald Mtn State Rec Area
        • POTA k-2314 Pine Lake State Park
        • POTA K-4429 Coronado National Forest
        • POTA K-4491 Superior Nat. Forest
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      • Ham Radio Field Days >
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      • Tuner/Matchbox >
        • ELECRAFT T1
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    • Going Mobile HF & VHF >
      • 2020 Mobile Installation
      • 2015 Re-install the Mobile
    • Miscellaneous Ham Radio Topics >
      • Baluns, Ununs, Etc.
      • Keeping wires and ropes untangled
      • Helping Others
      • Things Happen
  • Backpacking/Camping
    • 2020 Backpacking/Camping Season >
      • 2020 Oct Boundary Waters Trip
      • July 2020 Koehler-Andrea St. Park Birthday Camping Trip
    • 2019 Backpacking/Camping Season >
      • September 2019 High Sierra Camp Loop
      • August 2019
      • June 2019 Boundary Waters
    • 2018 Backpacking/Camping Season >
      • Oct 2018 Boundary waters
      • August 4-5, 2018 Wisconsin River Canoe Trip
      • July 16-18 Devil's Lake Birthday Campout
      • June 28-30, 2018 Backpacking/Camping
      • June 2018 ARRL Field Day Camput
      • April 2017 Ice Age National Scenic Trail
    • 2017 Backpacking/Camping Season >
      • July 2017 Camping at Timber-Lee Christian Campground
      • Cancelled Ice Age Trail Backpacking Trip
      • June 2017 Hiking/Backpacking/Camping >
        • Cave of the Mounds and Blue Mounds State Park
      • May 2017 Backpacking/Hiking/Camping >
        • May 19 Ottawa Lakes Campground
        • May 4-7 2017 Porkies Backpacking Trip >
          • Porkies Backpack Trip Day 1
          • Porkies Backpack Trip Day 2
          • Porkies Backpack Trip Day 3
          • Porkies Backpack Trip Day 4
      • April 2017 Backpacking/Camping/Hiking
      • March 2017 Hiking/Camping More Preparations
      • Feb 2017 Hiking/Camping
    • 2016 Hiking/Backpacking/Camping Season >
      • December 2016 Hiking/Camping
      • November 2016 Hiking/Camping
      • Oct 2016 Boundary Waters Canoe Area Trip
      • August 2016 Camping
      • July 2016 Hiking/Camping/Backpacking
      • June 2016 Hiking/Backpacking/Camping
      • May 2016
      • April 2016
    • Shelters >
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        • Reparing Tent Poles
      • Hammocks >
        • Hammock Stand >
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        • SnakeSkins or Sleeves vs. Stuff Sacks
        • Hammock Suspension
        • Keeping Warm in a Hammock >
          • Lite Top Quilt or Bag Liner
          • DIY Under Quilt
    • Glacier National Park 2015
    • Training for Glacier National Park Backpacking Trip
    • Backpacking Stoves >
      • Trangia 27-3 UL Stove >
        • Cooking with Trangia
        • ALOCS Trangia Look Alike Burner
      • Fancee Feest Stove >
        • Fancee Feest & Stanley Cook Pot
        • Another Cat Food Can Stove
      • DIY Alcohol Stove
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      • Lexada Wood-Gas Stove
      • Wood Burning Backpack Stoves >
        • Emberlit Fireant
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    • Backpacking Food >
      • Cowboy Coffee
      • Santa Fe Cheesy Beans and Rice
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      • Bacon Ranch Chicken Wrap
    • Other Gear
  • Adventures
    • 50th Anniversary In Alaska >
      • Day 1 Sites in Fairbanks
      • Day 2 Morning River Boat Cruise
      • Day 2 Afternoon travel to Denali
      • Day 3 Denali History Bus Tour >
        • McKinley Wilderness Princess Lodge Photos
      • Day 4 Coach ride to Anchorage/Whittier
      • Day 5 Ship Cruise at Yakutat Bay and Hubbard Glacier >
        • Photos of Yakutat Bay
      • Day 6 Galcier Bay
  • RC Planes
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    • Hobbico TWINSTAR
    • Other Planes >
      • Flite-Test FT-Cruiser
      • Micro Fokker Eindecker by Dave Robelen
    • Things I've learned....
  • About
    • July 12, 2017 Flood
  • Other....
    • Remembering Charles & Eva >
      • Feist Family Photos
  • KW4JM Contact Log
Ham radio is my longest running hobby interest. Things "electronic" caught my attention is a kid on the farm when I was about ten years old. Not quite sure why, unless it was the influence of my grandpa who was the lineman for the small crank-phone system in our part of the county. He took me with him on maintenance calls from time to time and gave me old phone batteries, transmitters, receivers, etc. Using some of that stuff I "installed" an intercom system between some of the buildings on the farm powered by a number of those old nearly-dead batteries in series. I also had an older cousin who messed with radio equipment of some kind. That impressed me too. Then during my freshman year in high school one of the boys club leaders at our church and a ham licensed neighbor each helped me and the boy next door learn the code which led to our novice licenses. Kenny, my neighbor let his license expire but I mostly never looked back after that.
The pages under this topic are kind of like a lab notebook, showing my approach to each thing discussed and the progression to either my conclusion or when I gave up and accepted the results! In nearly every case I'm looking for something practical rather than theoretical. Hopefully it is informed by at least some theory! I have date/time stamped them with the most recent at the top of each page and on some pages I've given a summery or overall description and some of the references that I found helpful. My hope is that it will be helpful to someone else.
Amateur radio a 21st century hobby

K0BXB

Ham Radio
QSO Today
4SQRP
QRZ
ARRL
First licensed in about 1958 as KN0BXB when I was a freshman in high school in Topeka,KS. Have been active since except for about 1985 through 2004. Today I work mostly CW on HF. Some SSB and digital.
Antennas are my current preoccupation. Also lower power. My primary rig today is an ICOM IC-7300l I've had it a few weeks and really like it. I still have an Icom IC-7100 but it is in a box right now while I decide whether to sell it or not. For QRP and portable I have a Xiegu X5105 which I love. It is just an impressive and capable rig in a very small package and fun to use. AND to top it off, I have a Xiegu G90 which is just a really great all round 20 watt rig. It is great for portable or fixed. For about nine months I used it exclusively. Now I like to take it to the back yard and pretend I'm in some exotic isolated place with just me and my radio! I have two base station antennas, an MFJ-1984 End Fed Half Wave 40-10 meter inverted vee, and a G5RV. Both serve me very well.
One of my main interests the past year or so has been very light weight wire antennas aimed at portable use along with light weight fiberglass or carbon fiber masts or fishing poles. ​I've got a bunch of "portable" antennas. A Sotabeams link inverted vee with links for 17, 20, 30 & 40 meters. A Sotabeams trap inverted vee trapped for 17, 20, 30 & 40 meters. A QRPGuys based "random" wire end fed with 29 and 35 ft elements. A QRPGuys based EFHW inverted vee cut for 40 and covering 40, 20 and 15 meters without a tuner, all the rest with a tuner. A Wolf River Coils TIA 1000 with their mini coil as well. And a home brew scrap box 1 meter diameter magnetic loop that is tunable on 40, 30 and 20 meters. Recently I put together light weight, portable vertical that is resonant on 20 meters and is tuned for 30 and 40 meters with a bottom loading coil. It works very well. I think of it as a wire based Wolf River Coils antenna but that is tapped for the three bands instead of infinitely adjustable. This preoccupation with lower power and "stealth" antennas may be moving me toward more portable operations. Perhaps more honestly, toward portable operating period! I've done a lot of it in my own back yard but very little "out in the wild". ​
PictureMillen 90800
My favorite vintage transmitter is this 1940's Millen 90800, just like the one I had back in the 50's as my first transmitter. I successfully tied the WA1FFL Direct-Digital VFO to the Millen which makes it a lot more versitle, if less authentic! I can still make it chirp wonderfully with the several FT-243 crystals I have. But I guess for true authenticity I should use the old Bliley CM2 7040khz crystal a local friend gave to me (see below). As he described, it does look more like an Oreo cookie than a crystal! ​

In high school my Dad bought one for me from a nearby ham as my first or second transmitter. I'm still amazed that I was able to get it on the air! During my college years that one disappeared (I think my mother sold or gave it away at a yard sale though she has always denied that!). I was on the lookout for one for many intervening years and finally found this one on eBay. It uses a 6L6 oscillator and 807 final. I don't use it often but every glance at it brings back wonderful memories and a sense of appreciation for the wonderful gear we have available today.
My favorite home brew rig was a little transmitter built on a wooden slat chassis first described in the Dec. 1946 QST magazine. It uses a single 6V6 tube and puts out 3-4 watts CW on 80 and 40. It's crystals also sing a nice tune - not the boring monotone of modern rigs. It would be hard to imagine a more basic transmitter. I had the privilege of publishing an article about it in the Nov. 2012 QST which garnered a large number of responses - turns out I'm not the only one who either buit or wanted to build this little jewel way back when!
After years of thinking about it, I finally made my own home brew straight key from scratch. I used the key dimensions from an old WWII Speed-x key. Contacts are from a retired relay. Spring is a badly worn hacksaw blade. I'm pretty happy with the way it looks, and it even works!
Picture6V6 Based Transmitter
This little 6V6 based transmitter was a really fun project, partly because it is so simple but mostly because of my childhood memories of it. I wanted so much to build one when I was in high school but just couldn't figure out how. So when I saw it in a QST article in 2011 I had to do it. An article I wrote about the experience was published in the November 2012 QST pages 46-48. I was flooded with responses. Turns out I was not the only one who either wanted to or did build it many years ago!

PictureHomebrew Key based on the Speed-X measurements
Here is my home made straight key. Based on measurements from a WWII Speed-x key given to me by a WWII Vet in Florida. The contacts are from an old relay and the spring is a re-purposed hacksaw blade. The wood was from an old bookshelf. Works well, though I prefer the real Speed-x key for normal operation. It's action is just not as "clean" as the Speed-x. But I keep it prominently displayed on my desk.

Finally, here is my mag loop antenna. This is an early version of it, actually the first version that "really worked!" It has since undergone a number of changes (improvements I hope). It is another of those things that I always wondered about but kind of "stood back" as it seemed somehow mysterious. Turns out there is nothing mysterious about it at all. In fact it is very simple. 
Which is a fitting way to summarize ham radio. It's simple, almost simplistic. We tend to make it "hard" with all the extra stuff but at it's core it's still just radio! Like fishing, the main thing is to get something into the water. If you keep worrying about whether you have the best lure, whether you have the right pole, whether the moon is right or whatever, you won't catch fish. But if you throw what you have in the water and eventually get a bite, you begin the life long learning - and humbling - process. Some days they bite. Some days they don't. Learn to enjoy the experience whether they do or not or regardless of how big they are!
Picture
Small Magnetic Loop tuning 30, 20, 14, 15, 12 and 17 meters.
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