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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The “New Carolina Windom”

Simplified diagram of a New Carolina Windom AntennaN. T. “Len” Carlson, K4IWL was a long-time DARC member before he retired to Florida, and his article about his favorite multi-band antenna was a popular page on our old website. I’ve looked in the club archives and found his paper for your reading—and on-air—pleasure.

Multi-band antennas can be very tricky to build and tune, but if you put in the effort required to adjust them, you can have a lot of fun.

Have a look at his article here.

Surprise Net 05-31-2021: Plan Bee

Drone bee with new dual-band amateur radio antenna. Credit: Joseph Woodgate

Plan A just wasn’t good enough, so surprise net tonight will feature Plan Bee! There will be no math and nothing too difficult. Join us on tonight at 19:00 local time on the 146.88 repeater.

I’ll probably add more links after the net…but here’s a great one to get started with if you’d like to help carry out Plan Bee: https://www.pollinator.org/pollinator.org/assets/generalFiles/pollinator-garden-cards_texas.pdf

And if that one was too simple for you, a more comprehensive guide is here: https://www.pollinator.org/PDFs/PrairieParklandSubtrp.rx3.pdf

Tech Net News 07-11-2020

Venus had a much neater ion tail back in the 1970s.

Would you like me to talk about impedance transformers (instead of baluns) at the next virtual Lecture and Lab? Would you like to build a simple, but high-performance balun? I’ll be planning out my lesson this Sunday, so tonight’s your last chance to give me your suggestions.

Field Day was exhausting, but great. But no job is over until the paperwork is complete. Please don’t forget: if you made even one contact, submit your entry to the ARRL and to the Dallas Amateur Radio Club. If you participated in the 13 Colonies special event, you’ll have to resort to postal mail…don’t forget to include some sort of address label; it can be a scrap of paper, and should not be an SASE.

The contest calendar for this week looks pretty quiet, but if Field Day got you in the mood to get back on the air—like it did for me—you should give in to the urge.

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Tech Net News 07-04-2020

A dipole will work just as well without a flag, but it will be less fun.

Our next club meeting is coming up this Tuesday, July 7th, at 7:00 PM. Like most meetings these days, it will be on-line. Please have a look at the club event calendar for the link you need to use. I’ll be giving the presentation and discussing one of the things I find most mysterious in our hobby: baluns.

I will speak at our next meeting about the basics of baluns, including how and why they work, what choices you have, and when to use them. Baluns can be easy and cheap to make for yourself, so I’ll will cover a few construction tips, too.

The contest calendar has a scattering of events, but the two most interesting are the 10-10 International Spirit of 76 QSO Party, which is is wrapping up this weekend, and the 13 Colonies Special Event, which is well under way.

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