Author Archives: Walter Underwood

Using a Mobile Antenna as a Temporary Base Antenna

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For our July Fourth Safety Watch this year, I used my dual-band mobile antenna on a ground plane mount on a camera tripod. I’d purchased a Nagoya GPK-01 NMO Ground Plane Kit ($28) to test my NMO mobile antenna, because my mag mount seemed flaky.

As I was drifting off to sleep one night, I thought that the 1/4-20 screw on my camera tripod might fit the holes on the ground plane kit. It did, so now I have a robust, free-standing, dual-band antenna for em-comm use.

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The antenna is a Comet SBB-5NMO with 3 dB of gain on 2 m. Not a flamethrower, but a solid antenna when used with a good ground plane.

The radials unscrew from the mount, so the ground plane kit packs up small.

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Our station was up on a hill, so we had great line of sight to the whole valley. We ran a mobile rig (Yaesu FT-8900R) at 50 W from a battery, so we had a great signal. We could also hear the other stations clearly, so our station was net control.

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The only thing I’ll change next time is to use 1/4-20 wingnuts instead of regular nuts. I might paint them orange, too. I was sure that I would drop a nut in the grass and never find it.

And yes, that is a classic Gitzo Reporter aluminum tripod. If needed, I could extend the center column to get the radials above eye level.

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Voile Ski Straps

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Better than bungee cords! I purchased a few of these, thinking they might work for strapping my fiberglass radio mast to posts and stuff. They are great. Stretchy, adjustable, and super easy to fasten and unfasten. After I tighten a strap, just releasing the tension almost always catches a hole on the buckle to secure it. Lovely design.

Here is one of the two I used to strap my mast to a railing on top of Mt. Umunhum for a SOTA activation. My shortest straps are red and 15 inches long.

Voile 1

Earlier, I used a longer blue one (20 inches) and two of the red ones, linked, to strap the same mast to a walkway post for ARRL Field Day.

Voile 2

A red strap held the balun to the top of the mast to take stress off the connectors.

Voile 3

I started with this variety pack of three sizes ($16.50 at Amazon), then stuck with the same color scheme for ordering more.

I’ll be taking these on every field radio outing. That means I’ll have swap them back and forth between my emcomm go bag and my SOTA gear. I think I can manage that.

Bargain Ultralight: Mountainsmith Mountain Shelter LT

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Want to try a single-wall ultralight tent without spending a lot? How about the Mountainsmith Mountain Shelter LT, a two-person shelter that weighs less than two pounds for $100?

Mountain shelter lt 5

I used to recommend the Black Diamond Betamid for this, but BD stopped making it. Now Mountainsmith is making a very similar shelter. It sets up with two trekking poles, like a small circus tent. It is lighter than the Betamid, probably because Mountainsmith used silnylon instead of the urethane-coated ripstop in the BD shelter.

The Section Hiker review of the Mountain Shelter LT does a really good job of describing the tent. I’m seriously tempted to buy one, even though I have more than enough shelters.

The list price is $129 and it is available for a bit under $100. Links are from the Section Hiker blog.

This tent doesn’t have a floor, so you’ll need a groundsheet. My favorite thrifty and ultralight groundsheet is plastic window film. It costs five to ten dollars and weighs an ounce or two, depending on the size. For this tent, two one-person sheets might be good. Two popular products are Duck Brand and Frost King. I’ve never worn out one of these sheets, though I’ve been in danger of having them blow away. They are really, really light.

The Section Hiker blog has a nice article on ground sheets, including window film and Tyvek.

I wrote about my son’s experience with the Betamid at Philmont. He’s still fond of that tent. I hope a whole bunch of Scouts become fond of this one.

Whip Antenna Support for KX3

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A Nite Ize Gear Tie seems to do a decent job of supporting the MFJ-1820T 20 m whip antenna on my Elecraft KX3. I first tried forming it into a bipod, but then got the idea of attaching it to the SideKX endplates. Success!

KX3 gear tie 1

I’m using a Nite Ize Gear Tie 12 inch because I had one. The fatter one didn’t really fit through the handles.

The whole setup is pretty cheap. $25 for the antenna and $6 for two gear ties. It isn’t as efficient as a 20 m dipole, but it is kind of cute.

Mark Your Stuff: White Electrical Tape

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Did you know they made electrical tape in white? It takes Sharpie like a boss and sticks to everything. So get a roll and start marking your stuff.

Get the best tape because it is only $6 and will last a long time. I use Scotch Vinyl Electrical Tape 35.

White tape 3M crop

Let’s mark some antennas, because all the rubber duckies look the same and they are all designed for different bands.

White tape antennas

Let’s mark my awesome insulated coffee container, a gift from my son.

White tape coffee crop

And let’s mark the very nice thermos I got at work.

White tape thermos

If you want to know the details about this tape, like being good to 105º C or having 10**6 megaohms resistance (that is a teraohm, right?), check the data sheet.

Also, if your Apple cords are getting frayed, this is a stylish way to fix them. So get some tape and mark your stuff.

23cm PC Board Yagi

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I wanted a bit more “oomph” from my 1W 1.2 GHz HT, so I purchased a PC board Yagi to get another 6 dB.

I have a Yaesu FT-911 1.2 GHz HT. It is a 1990’s rig gifted me by the wife of a Silent Key at my work. It is a sweet handheld, but with limited power.

WA5VJB makes a variety of PC board antennas. The 1.2 GHz 3-element Yagi is $6, which was hard to resist. He also makes other nice microwave antennas: log-periodics, patch arrays, wheels, vivaldis, etc.

I went to HSC Electronic Supply and picked up a PC mount BNC and a right-angle BNC by navigating this aisle.

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I found a short, stiff BNC cable from this bin.

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I soldered on the BNC chassis connector and epoxied it to the antenna. The PC board is beat up because I’ve been carrying it around in my backpack for ARRL Field Day. It was pristine when I got it. Nice design, the feedline attaches at the edge of the board, then there is a stripline to the driven element. The reflector element is on the back side of the board. You can just barely see it in this photo. The shield of the coax attaches to a thru-hole pad that goes to the stripline on the other side of the board. That is hidden by the connector in this photo.

23cm yagi 1

And now I have a 1.2 GHz “flamethrower” HT.

23cm yagi 4

I need to find something to stiffen that bit of coax so I don’t have to use my hand to stabilize it. Other that than, pretty sweet.

Skillet Lasagna

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Made this tonight and it was tasty. This is a simple one pot meal, just right for Cooking Merit Badge. Scouts will learn to dice an onion (not required for the merit badge, but an essential skill), sauté the onion (also not required and also essential), and brown meat (which is always tasty).

They should also learn a bit of “mise en place”, getting everything ready and in its place before starting. The recipe doesn’t make that clear, but a mentor (Merit Badge Counselor) should walk them through prepping the tomatoes and onion first, then getting the other ingredients ready while those are cooking.

Skillet Lasagna

Recipe for Skillet Lasagna.

The first time you stir this, you will probably wonder about using lasagna noodles. Next time, I might use a different pasta shape. Maybe rotini (corkscrew), penne (tubes), or farfalle (bowtie). Or I might go with lasagna again. That did work, despite the concern while stirring.

A bit more ricotta, basil, parmesan, or whatever is fine with me. I’m always good with more flavor or richness.

The recipe calls for a “meatloaf mix” of ground beef and pork. I bet that would be tasty, but we used 85/15 ground beef. 80/20 might be better, but you can always add a bit more olive oil.

Dicing an onion is one of the most basic skills in the kitchen. Doing it wrong is a good way to slice your finger. So watch this knife skill video from Kenji López-Alt and learn to do it quickly and safely.

Sautéing onions is not hard, but requires attention. A bit of oil, cook over medium high heat, stir occasionally (avoid burning), until the onions are translucent and tasty. Add more oil if the skillet is dry.

Cooking Merit Badge requires understanding frying, but sautéing isn’t quite the same thing. Frying is done at medium to medium high heat with plenty of oil and large pieces of food. The food is not moved around much so that it can cook through and brown. Like fried chicken. Sautéing is at higher heat, medium high to high, uses less oil, food is usually in smaller pieces, and stirred more often.

This article on Sautéing vs. Pan Frying is short and clear.

The recipe calls for minced fresh garlic, which is kind of a bother. We keep a jar of minced garlic in the fridge. It doesn’t taste quite as good, but it sure is easier.

Bon appétit!