Club News

My Magnetic Loop Antenna

Richard Robbins, WA8RR I had read in several articles, the building and use of magnetic loop antennas. I found the following website: http://www.66pacific.com/calculators/small-transmitting-loop- antenna-calculator.aspx. This web site allows you to enter various values for the main loop. I was interested in 40 and 20 meters. I decided on a loop of 10 feet in circumference using a piece of ½ inch copper pipe. I wanted to run 100 watts because that is what my ICOM 7300 could put out. The calculations provided the following. I found a piece of 10 foot copper pipe at a local plumber. I located a capacitor that looked like it would work from the Hamvention. I didn’t have any fancy tools. I hand bent the pipe into an approximate circle. It will never win any beauty awards. However, I constructed a drive loop out of coax, connected the coax to my RigExpert and found that the antenna would tune. General observations. The antenna would tune 20 meters. To tune 40 meters, I added a piece of coax in parallel to the variable capacitor. Tuning is very sensitive. I used a 10 to 1 reduction drive to adjust the capacitor. Body presence and metal affect the tuning. I ended up adding a remote control to the antenna using a 1.2 rpm dc motor. With the configuration as shown above, I was able to make several contacts on FT8. I would use my RigExpert to tune it. The tuning would shift as I was transmitting. This is a result of a very high circulating current and heating of the separate components. Encouraged by the results, I decided to take what I had learned and redesign. I found a 10 foot 1 and 1/8 inch thin wall copper pipe at Menards. Located a local metal fabricator to bend it…the process needs a roller bender. The results were good. I replaced the variable capacitor with a vacuum capacitor. The vacuum capacitor is expensive. However it seems to be the goto device for this type of application.

KE8O Update on N8OB’s sale

I’ve had success selling a lot of Bob’s equipment for Marcella. The following are new items located: LDG 600 Pro ATU w/box $200 Yaesu FT60 HT w/drop in charger AND programming software w/cable - Make Offer I plan to bring the following to the next meeting 2 Older bench model DVM’s 2012 ARRL Handbook Misc jumper cables and connectors

Jamie in the park

(sung to the Chicago tune!)

Today I decided to see if my antenna pole would work with the antenna attached. As it turns out the initial way I was thinking of using it as a free standing pole was a fail. D'ohhhh. It was far too unstable for my liking. I don't need a major failure that might get someone injured. Namely me. So I went back home to think about it. Ohmmmmm. So I decided to use rope as guy lines at each section. That equals x3. I already had the middle ready so I repeated the steps for the bottom and tip top. This time the pole is very much more stable and adjustable for each point. As seen in the images, I ended up with a mini tower where the antenna feed height is at 22'. I was able to pull and release the antenna up and down with no issues. The top support is about 18" from the pole and should work well. I didn't get to power the antenna but hopefully I can do that tomorrow. Oh, I also made 10 and 6M wire to add to it. So this has the potential for 40, 20, 10 and 6M. The top support needs a small mod to be a bit better. It took some time to figure out the set up and is a bit more involved but I am making what I have on hand work. I'm tickled. So I need a name for this set up. What do you think it should be called? Oh, with the wind the guy rope sings. How cool.

The Miami Valley Steam Threshers

2019 show is coming up in July.

Will, N8HDM, has been operating a special event station during the show over the last several years but will not be available this year. He has asked Ed, KE8ANU to head things up this year. He will need some help setting things up and operating. The show itself is a ton of fun so bring the family! Please contact Ed or Will to volunteer. ke8anu@arrl.org will.hoffine@gmail.com

Help Wanted: Scouting Radio

Last June DELARA was asked to conduct a one day ham radio demonstration during the Delaware District Cub Scout day camp. We conducted three sessions with Arrow of Light kids only. The AOL kids are in 5th grade. The camp staff was so impressed that they have asked us to return this year, with one additional request - they want us for the whole week and to work with ALL the kids. On camp that week will be HUNDREDS of Cub Scouts in grades 1-5. The day camp staff has been working more STEM (science, technology, engineering, and math) activities into the camp program. In order to pull off 5 days of hamming, we're going to need a lot of help. Wally W8WLK, Joe K8MP, Bob W8ERD, Steve K8SWH, and myself are already lined up. These fine gentlemen helped with the Scout day camp event last June and/or with Jamboree on the Air (JOTA) in October. We still need more help! Volunteers can opt to help for one day to all five days, or anywhere in between. Partial day assistance (at least four hours) could be useful, too. Day camp will be June 24-28th this year. That is the week immediately after Field Day. It also means we need helpers to set up antennas, extension cords, tables, stations, etc. the Thursday or Friday before. I know, it's the same time as Field Day setup, but how many opportunities do we have to get HUNDREDS of kids on the air? I think we'll need at least FOUR people each day for the five days to operate radios, interact with kids, demonstrate HTs, mesh, DMR, CW, or anything else we can do to keep them occupied while they wait a turn on the microphone. Having SIX hams each day would be even better. Even if you can just do one day of the event, or help setup or tear down would be huge! I have negotiated the following amenities to make this a successful event: • An open field surrounded by trees near the swimming pool bath house (running water and flush toilets!) - lots of room for antennas • A 10 x 20 barn with locking doors for our "shack" - setup radios once for the week • A 10 x 20 portable garage (like a giant tent) for information tables, sign-in sheets, etc. • A golf cart for our exclusive use - in case hams need help getting from the parking lot to our area • Access to 110v power (via extension cords) Please let me know if you can volunteer for any amount of time and I will add you to the list. Like last year, I will conduct a series of conference calls to plan and organize the event. I would like to host our first call in the next week or two. https://www.kb6nu.com/delara-demos-amateur-radio-at-cub-scout- day-camp/ -- Ed Jones - K8MEJ - Lewis Center, Ohio U.S.A