September 2023 Lecture and Lab: build an active fox hunt attenuator

If you’ve ever tried to find a hidden radio transmitter, or if you’ve ever wanted to…or if you’ve ever wondered how close you could get to finding a “jammer,” this month’s Lecture and Lab is for you!

We’ll be building the KC9NON active attenuator kit, an easy-to-build device that lets you get up close and personal with the radio transmitter that you’re hunting. The kit cost is only $20.00, and the tools needed are simple: a soldering iron, solder, wire cutters, wire strippers, and a small screwdriver are all that you really need. A hot glue gun and a needle-nose pliers were enough for me to finish my build. You’ll also need a jumper cable with BNC connectors (it can be very short, 2 feet is plenty), and a BNC-equipped antenna and radio, or else a set of adapters.

We’ll be meeting at 10:00 AM on Saturday, September 23rd, in the 3rd-floor community room at the Dallas Medical Center, 7 Medical Parkway Dallas, TX 75234. There are 15 kits available, first-come-first-served.

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Antennas Mentioned on the July, 2023 Fun Antenna Surprise Net

My thanks to all the hams who participated! Antennas mentioned tonight included:

The homebrew Buddipole was mentioned by Tony, NT5TM. He presented this at the July, 2017 DARC meeting.

Bill, N5BB, mentioned using a bedspring for QRP contacts at a past IARC Field Day, as well as using a balloon to hoist a wire antenna into the air.

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July 2023 Meeting Presentation: Fox Hunting on the Cheap

Anthony Mendina, NT5TM, is pictured next to the marker tag for a hidden radio fox.The July, 2023 DARC meeting presentation, titled “How I Got Started in Fox Hunting Without Spending Much Money,” will be presented by Tony Mendina, NT5TM. He’ll talk about the very basic equipment that’s needed for VHF and UHF fox hunting—which most hams already have—and the step-by-step process of finding a fox that works best for beginners. He will also discuss some optional, easy-to-build equipment that you can use to improve your hunt experience, advice for planning a route around danger, the technique of using a map to save time, and good (and bad) places to take a bearing. A special bonus activity of poison ivy recognition practice will be included!

If you missed my presentation, please have a look!

Getting Started in Fox Hunting: Saving Money, Having fun, and Avoiding Poison Ivy

Field Day 2023 Statistics

Dallas Amateur Radio Club 2023 Field Day Sections Worked Map

Field Day 2023 was once again held at the Johnston Outpost YMCA, and the air-conditioned location was a big success: the club was able to keep all 3 radios in operation for the entire event! As other clubs wound down their operations, operators came to visit our site late at night on Saturday and early Sunday morning, providing welcome support. We managed to bag Maryland a few times on Sunday morning, but the San Joaquin Valley eluded us this year.

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Lecture and Lab, August 2022

The QFH Antenna, courtesy of Eugene Ruperto, W3KH

The latest revision of the instruction sheet and information guide is now available. I’ve also added some information about on-line resources.

The August, 2022, Lecture and Lab will be held in-person at the Dallas Medical Center on Saturday, August 27th, at 10:00 am. We’ll have an antenna build and a presentation, too. The antenna we build will be a 137-MHz helicoidal loop antenna pair for receiving weather satellite images and aircraft radio voice transmissions. The presentation will discuss the best software tools for decoding satellite imagery for yourself. The antenna will be very easy to build, and the cost will be only $30.00. 20 kits will be available!

You’ll need to bring a soldering iron and some general hand tools such as a tape measure, a sharpie, and your favorite set of files. The club will provide the antenna parts, but not the receiver: you’ll want to have a device that can receive signals at about 137 MHz. Most ham radios can’t do that, so now’s the time to check on your scanner or even order an RTL-SDR dongle or one of its competitors like an Airspy or SDR-Play. You’ll also want an adapter from a PL-259 connector to whatever connector your receiver uses.

I hope to see you there!

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Field Day 2022 Quick Stats

Map of the United States and Canada, showing most states and provinces colored in. Alaska and the maritime provinces are not colored in.
2022 Dallas ARC Field Day Section Map

Field Day 2022 was a great event, from the well-prepared set-up to the well-orchestrated, fast take-down. As Randy, KE5JIT, pointed out, a 55-minute “strike” is clearly a record for the DARC. While the Field Day committee works on the final entry, please enjoy some fun facts and numbers about our Field Day contacts.

I’m proud to say that team “TM” did a great job making contacts! It was only on Sunday morning that Travis McWaters, KI5PGM, pointed out to me that he was using the same initials that I, Tony Mendina, NT5TM, used. Travis made many more contacts than I did.

At least 20 of the 51 people who visited our site made at least one contact on the air. (Not everyone entered their information into the logging software.)

Details about our contacts are below.

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DARC Lecture and Lab August 2021

These are the easy-to-build cores of the 1:1 balun and 1:49 transformer you’ll be assembling.

Join the DARC for Lecture and Lab August 28th, 2021 from 11am until 2 pm Central Time virtually via Google Meet. (The virtual meeting ID/Link is always on the W5FC event calendar) You will get to build two easy kits: a 1:1 choke balun and a 49:1 impedance transformer. Both will be enclosed in waterproof PVC enclosures and neither kit will require precision soldering. The balun will be constructed to hang below the center of your dipole, and the transformer will be set up for use at one end of an end-fed half-wave antenna. To pick up your kit, you will need to come to the front parking lot of the Dallas Medical Center on August 21st, 2021 from 10:30 – 11:30 to pick up your kit from the Dallas Medical Center parking lot from Tony, NT5TM.

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