It has been relatively quiet around Uretopia Ranch this weekend.
The “Christmas Room” (solar addition) was “red-flagged” by Elaine early in the week. She was initially OK with the idea of an attached greenhouse. But, not so cool with the color of Penofin. It goes off to a medium orange/red. Very much like Redwood with a coat of sealer on it. There’s rosewood oil in Penofin, after all.
After several days to think about it though, she acquiesced. (I then dropped the “hurt-puppy look.”) But with a condition: “It would be OK if it went with the color of the house (beige) and the trim (flat black). If you can do it that way, then OK. Otherwise, it comes down.”
The problem on my side of things? Although the design was solid, and the initial verbal description was honest, the “actual” of all those beams admittedly is that it blocks a lot of her view. (For 3-minutes a day.) Subdued with black paint it would be OK. Though, an Inspector with flags worries me no end.
One of my “red-flag options” was to number everything as I took it all down, then reverse the order and make it a “Kit” for future use. There are several such kits out in the shop. Jigs and rigs that are seldom used, but once needed, swore I’d never be without ’em. One example is a wire-spool handler for long ham radio antennas. Built it, a dozen parts or so, then disassembled numbering as I went. Boxed and ready when needed.
The “red-flag” will be on for a week, or better. Not only is there the matter of black oil-based exterior paint (you can’t safely put latex over an oil-based stain and the stain had better be cured first when you put on an oil-based…). There’s the little matter of weather.
As of click-time today (I was up at 3 AM) it was about 26F with a decent 20-knot wind coming down from the north. All the closer to Colorado we care to be. Point, though, is that it will be a week, maybe, before the beams are re-coated and the project resumes.
25F and scattered snow by 5:15 AM.
Ham Radio: Thank You W7EL
I want to offer some heart-felt thanks to Roy Lewallen this morning: W7EL is retiring from the development and evolution of what – for my money – has been the finest ham (and commercial) radio antenna modeling software in the world.
IT’S NOW FREE! Read-on!
Roy’s retiring and – in one of the most stylish moves ever – he’s made his programs available free. Visit EZNEC Antenna Software by W7EL to download.
Believe me, I’ll be doing the update to EZNEC version 7 when it’s released in a couple of weeks, too.
In the meantime, I wanted to express heart-felt appreciation. Not only for his advancing of the hobby (ham radio), but also for the perhaps hundreds of hours of enjoyment (and learning) I’ve gotten in antenna design using his platform.
Just for example, when I was young, my (also ham) buddy The Major and I would lust after higher and bigger antennas. Yet, after doing a ton of models trying to get the “absolute most” out of 20-meter (14 MHz) antennas, it turns out there are “sweet spots.” We were surprisingly close at 40-feet up.
My present antenna lash-up is the “Super Antenna” which is oriented east-west and (memory going here) either a Buxcomm or Buckmaster OCFD going north-south.
Mysteries of the OCFD
My “big” antenna (east-west) sits up at 55-feet in the middle, 65-feet on the west end, and about 80-feet on the east end.
Modeling it has been both a joy and curse. Because sometimes, depending on how things are arranged, you’ll see a flag on an antenna pattern far-field display advising “Model contains loss.”
In which case, you take the loss information, reverse sign, and add that to the far-field display.
Say you test an antenna that reports gain of just 4 dBd (decibels gain over reference dipole) and the “Model loss” is -2 dB, then the actual antenna performance will be +6 dBd in real-life. Quiz?
Similarly, 13 dB of display gain with a “Model loss” flag of +5 dB means in reality performance will only be about 8 dBd. (Remember, reverse sign, so 13–5=8…)
If you’re lucky, that is.
There are so many variables it will make your head spin. Not just “how long and how high” but is the wire insulated or not? What diameter is it; #14 or #8? What is the soil conductivity where you live? Do you have a buried ground system? What does that look like? Antenna matching sections? The list goes on.
More Complicated than a Woman
Antennas (as an old geez) are a lot like trying to figure out the spouse. It’s a Nobel project, one you can pour a whole life into. Yet, approximations often don’t work out. Which sends all us males back to the drawing board for recalculations. Been recalculating more than 20-years now.
Yet – in the same sense as knowing (in chess) that The Immortal Game was a chess game played by Adolf Anderssen and Lionel Kieseritzky on 21 June 1851 in London, the design of that perfect multi-band wire ham radio antenna is illusory.
G. E. “Buck” Rogers Sr. wrote a book a while back that every serious “Antennist” ought to have in their collection: the-windom-handbook.docx (live.com). It opens as a Word Doc or save-as then do what you will.
Newbie hams often think an OCFD (off-center-fed dipole) and a Windom antenna are the same thing. However, they are not. And separate from these is the Carolina Windom which is sold by RadioWorks. See the diagram at CAROLINA WINDOM (radioworks.com) for an idea about construction details.
So far, Super Antenna has been going through a series of design evolutions experimenting with the “vertical radiator” idea. Nelson Antennas (search “nelson” in the ham radio section of eBay for ’em) makes a very good quality RF line choke.
So far, the simple OCFD is working better than the antenna with the “vertical radiator.”
This has fed back to looking at antenna matching issues, since the best radiating performance of an antenna is seldom at the ideal feed line matching point. While 4:1 baluns (a balanced-to-unbalanced RF transformers) are common, a 3:1 balun may end up being built here, simply because it’s in ultra-fine tuning where the difference between a “good” antenna and a really “GREAT!” antenna can be made.
Between EZNEC and the “Buck” Rogers book, you can spend a lifetime or two searching for the “El Dorado” of antennas. Hopefully, you’ll have better luck than I have. Nor am I alone. Wm. of the Radio Ranch may be onto it when he takes a simple half wave long wire (called the end-fed-half-wave or EFHW) and just goes and has fun.
This is like the problem of sorting-out fishermen. Wm. would be that lucky nimrod who, upon feeling the urge to fish, simply finds rod, reel, hook, worms, and proceeds to have fun drowning worms (maybe a beer) and catches fish.
Ure is not so lucky as Wm. Ure is more the “First you build a 12-foot, four section, bamboo casting rod. Then you tie a special fly. Now, to track result’s, we’ll dust off a copy of Foxpro 9 and build a tracking database…”
The Wm.’s of ham radio always get more fish – on ham radio, that’s more DX (distant stations). Because of the “LAWS OF FISHING: RULE #1.” Which reads, lest you’ve forgotten: “A line must be in the water to catch fish.”
Converted to electronics: Wm. turns on his radio and begins to “catch fish.”
Ure doesn’t get around to dropping a line in very often; he’s still waiting for the bamboo varnish to dry and he’s stuck troubleshooting a procedure call in Foxpro. (Other than eavesdropping and an occasional “Howdy” on 3785 on slow news mornings, I don’t want to try that antenna without a database to track results, lol….)
CNC Laser Delusions
I think all of us who fancy ourselves “Makers” have dreams of the ultimate CNC mod for home users.
Off with the spindle motor and on with the laser!
Lately, I’ve been studying up on the LaserTree high power laser add-ons for the low-cost home CNC market. Some claim to be able to cut 1/2-inch plywood (usually in 2-passes) and seem in the 80-watt range. 12V 3-wire here, thanks.
My research continues. Meantime, I’ll be adding a bit more content this year over on the Ultra-Make.com site one of these days. Still in migration from old website to new.
Shop Plans 2022
In case you have not read today’s column as an intelligence analyst, from the top, let’s sum it up:
- Ure’s excuse this week on the Christmas Room project was Paint. Weather excuse is on deck.
- His computer time since the year began has been poured into EZNEC.
- Ure’s still looking for Antenna Eldorado.
- He’s also distracted with laser CNC dreams being too cheap to drop $20 thousand on a waterjet rig.
- He rambles slowly ahead; still unable to solve that procedure call in Foxpro.
Yep, little doubt about it: 2022 won’t be much different than 2021. Except for the gardening part or you could face starvation…
Write when you get rich,