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ham radio

Odd Lots

May 16th, 2020
by Jeff Duntemann.
20 comments

Boy, writing this entry just felt good. I gotta do more of these…

  • People are asking me what’s happening with Dreamhealer. (First chapter here.) I’m working with an artist on a cover. The ending needs a hair more editing, but after that it’s an afternoon’s work to lay out the ebook in Jutoh. I had intended to introduce it at LibertyCon mid-June. Lacking a LibertyCon, I’m now just intending to get it out as fast as I can.
  • Are any of my ham friends (general or higher) interested in an experimental sked on the low bands? If so, where have you heard Phoenix? I usually try 20M before anything else, but if anybody’s got any heuristics, let me know somehow.
  • Everybody (ok, every nerd) knows about the Carrington Event. Even I didn’t know that we had another one of those in May 1921. Although Carrington is more famous, by strictly objective measure (the disturbance storm time index, or Dst) the two solar storms were almost exactly alike. In both cases telegraph stations caught fire from currents induced in the wires, and a lot of telephone equipment (which wasn’t deployed in 1859) was destroyed in 1921 by the same induced currents. Damn, like I needed something else to worry about.
  • I’ve backed a number of technologies before. Risky business. I backed Wi-Fi back in the early oughts and won big.I backed WiMAX and watched it swiftly and silently vanish away. I backed Powerline networking (now gathered under the umbrella term HomePlug) and lost but still use it. Here’s a good article on what happened to both WiMAX and HomePlug.
  • One technology I haven’t backed yet is 5G mobile, which is finally getting some traction in the marketplace. My LTE phone works just fine, and I don’t stream video to my phone. (I have a big honking TV for that.) Where I think 5G is most promising is as competition to the mostly monopolist residential broadband providers. We have cable Internet here, and it’s…ok. If 4K (or God help us, 8K) video is to have a chance, it will be through the benefits of 5G, and not otherwise.
  • Neil Ferguson’s computer model of the COVID-19 pandemic caused the UK’s lockdown. Now it comes out that the model was a good design with a trash implementation. (This from a computational epidemiologist, who just might know a crap pandemic model when he sees one.) Imperial College refuses to release the original model’s code and is making stupid excuses why not. A fragmentary and much-jiggered source code suite is now available on Github, and includes things like a global variable struct with 582 fields. (And lots more global variables.) Uggh. Her Majesty should demand her people’s money back.
  • A San Diego County supervisor stated that only six of 194 recorded coronavirus deaths were actually caused by the virus. The others died with the virus, but according to the supervisor, not of it. Yes, yes, I know, it’s not either-or. COVID-19 can push an elderly heart or cancer patient over the edge. Still, we need solid numbers on how deadly this thing is, and for that we have to back out the count of people who were already dying of other things.
  • Here’s a good example: A Colorado man died of alcohol poisoning. (0.55%, when the supposedly lethal threshold is 0.3%.) He was tested for coronavirus and found to be carrying it. So he was listed as dying of COVID-19. He had no comorbidities, beyond enough booze to kill a middling elephant.
  • The county I grew up in now has more COVID-19 cases than any other county in the US. Good ol’ Cook County, Illinois. I guess we got out in time.
  • In good news locally, Taiwan Semiconductor Manufacturing Co. is announcing plans to build a $10B plant in Arizona. Is it possible that those jobs are coming back? (Sorry, Steve.)
  • Now that we’re all obliged to wear masks, it was inevitable: Gait recognition technology is in development. It uses deep learning and sensors in the floor. This is more than a little creepy, granting that we once said that about face recognition as well. I recall a friend (now deceased) telling me in 1976 that “You walk as though you’re on your way to kill something.” (That was partly ROTC marching and partly the need to walk fast from one busted Xerox machine to another in downtown Chicago.) Maybe I should buy a scooter.

Plaguewander

May 11th, 2020
by Jeff Duntemann.
8 comments

How serious is this lockdown thing? Well, I’ve won all 1600 boards on Mah Jong Titan. That includes all available premium board packs. If there were more I’d buy them. There aren’t. That doesn’t surprise me, given the work it must take to produce another 300 boards that only the occasional crazy like me will ever play.

I’ve played Mah Jong for decades, and not just to kill time. For me it’s a sort of mental palate-cleanser: I play a board or two when I need to shift gears from one project to another. When I move from working on Dreamhealer to some construction project out in the shop, I play a board to stop me from thinking about Dreamhealer, or at least to pull me down from obsession territory. It does work. I’m not sure why, given that Bejeweled doesn’t provide the same benefit, nor do any of several other games I’ve tried. My theory: Mah Jong depends to a great extent on memory. Playing well requires remembering which tiles are where on the board. You’d think that that would be no big trick, given that the board is already laid out in plain view. Not so. A few tiles stand out from the crowd. Most do not. If a move uncovers a four of bamboo, you had better know if there’s a four of bamboo elsewhere on the board. The games I play, at least, are played against a clock. You don’t have a minute to scan the whole board to spot that four of bamboo over in the lower-right corner. Dead-time adds up, and each board has a time limit. To win the board, you have to empty it within that time limit.

The creative life is all about memory. This is true of fiction, especially the fiction that I write, which is heavy on ideas, foreshadowing, and gradual reveals. Getting away from fiction means remembering other things for awhile. And because Mah Jong is a shallow memory challenge, it takes little or no effect to push a board full of tiles out of the forefront of my mind when it’s time to turn to something else.

-…- -…-

Carol and I did some shopping at Wal-Mart today. I don’t know if this was their innovation, but aisles at Wal-Mart are now one-way. This makes it easier to stay away from other shoppers, though it can be a nuisance at times. I tend not to go shopping when I’m feeling impatient. Mercifully, I was not feeling impatient this morning.

-…- -…-

While at Wal-Mart, we looked at Polish sausage and other sausage products. I typically eat a bratwurst or some other similar sausage for lunch. There was a run on such things for awhile, and I was unable to find the Hillshire Farms smoked sausage that I’d been lunching on for some time. We saw them at Wal-Mart today. I picked up a pack, and scanned the list of ingredients. Yikes; they now put MSG in their smoked sausage products. I originally chose them because they did not include MSG. Johnsonville sausage products, on the other hand, have been nonstarters here for years, because all their sausages contain MSG. Well, since I was reading labels anyway, I picked up a package of Johnsonville smoked bratwursts and scanned its ingredients. No MSG! So I bought some.

It is a puzzlement. Given how many people react badly to MSG, I have to wonder why sausage companies insist on using it. Does a sausage really taste better with MSG than without? I can’t tell the difference and never have.

-…- -…-

Cutting Board Before-500 Wide.jpg

54 years ago, I took wood shop at Lane Tech in Chicago. We built a number of projects, but the only one that survives is the heavy oak cutting board. My mom used it while I stilled lived at home, and I took it with me when I moved out and married Carol. So it’s been in use for all 54 of those years. The board’s saggita is now half an inch, so we flipped it over and now cut on what was the bottom face.

Alas, the two outer oak layers on the board started peeling away from the rest a few years ago. Food was getting caught in the resultant cracks, and I was afraid I’d have to toss it out. Not so: A little careful work with my chop saw and some belt sander time yielded a narrower but now far more hygienic cutting board. This may not last, and the day may come when I can’t cut any more layers off the edges. Still, 54 years is a long time to be using an artifact that you built yourself with your own hands.

-…- -…-

My fellow hams don’t need me to tell them that the bands are dead right now. The very occasional sunspot is so small I often wonder if it’s dirt on some telescope’s lens. Propagation is lousy. Working Wisconsin was a delight. Working Seattle almost knocked me off my chair. But beyond the current sunspot dearth, what really annoys me is the noise level. I thought for a long time that this was caused by the crappy switching power supplies inside every LED bulb in the house, which would be all of them but two. (The two incandescents are grow lamps for Carol’s African violets.) So I did the experiment last week: I shut off every piece of electronics (including the AC) and every damned lightbulb in the house.

The noise level did not change at all.

I can’t shut off the security system and really don’t want to. But I’ve had security systems in every house we’ve lived in since 1990, and have never had noise levels like this. The houses here are widely spaced (this is the land of half- to one-acre lots) so I suspect I’m not hearing the neighbors’ stuff. All the more reason to buy a 12V battery pack and enable the Icom IC-729 to run on battery power. If the power ever goes out in our neighborhood, I’ll make a beeline for the shack, to see if the noise level drops. That won’t help me work Wisconsin once the power comes back on, but at least it’ll narrow down the culprit list a little.

-…- -…-

Dreamhealer is coming along. I’m still doing some edits, but in truth, I’m waiting for the artist to finish the cover. I was going to release it at LibertyCon in June, but there will be no LibertyCon this year. My deadline, being dead, no longer has much force.

-…- -…-

Arizona is opening up. Carol’s going to her hairdresser to get her hair done on Tuesday for the first time in quite awhile. The next time I need a haircut (I know, I know, during the next Ice Age) I’ll be doing the same thing. We’re being careful, but we’re no longer cowering at home. I’m watching Arizona stats for a number of reasons, the main one being that we’re already most of the way to a long hot summer. Viruses in the Sun die in seconds. No data on how long they last in triple-digit air out of direct sunlight, but I suspect it shortens their viable stage by a lot. Viral load is, as best we can tell, a factor. So we don’t go to concerts or political rallies. (Actually, I have never gone to a political rally. Viruses are not the reason.) We used to go to sit-down restaurants maybe once a month. We have carryout service accounts now and know how to use them. Total Wine is open, as are most other stores that we frequent. My motto remains what it is and has always been:

All will be well. And all will be well. And every damfool thing in the universe will be well!

The Not-So-Fondly Farenheit Tuner

Oct 29th, 2019
by Jeff Duntemann.
9 comments

AH3 and AH4 tuners - 500 Wide.jpg

I’ve been slow to come up to speed on the radio front since we’ve moved here. Until March 2017 we were bouncing back and forth between Phoenix and Colorado Springs, furiously working on both houses, one to sell, and the other to live in. Given that I was trying to write a new novel during that time (and was now in my mid 60s) time was tight and personal energy scarce. But more to the point, I wanted to do it right. Most of the trouble I had with my station when we lived here in the 90s was a lousy ground system. A year or so ago I took the time and built a Bentonite ground with a water pipe down the full depth of the Bentonite to keep it wet, ideally with Epsom salts in solution. The ground rod is right next to the entry box through which all my cables go through the wall of the small garage where my station is.

With the ground in place, I strung 75′ of #16 solid copper between one of my two big palm trees and the mast on the roof of the garage, where the TV antenna used to be. On the mast I mounted my venerable Icom AH-3 autotuner. I had to make an extension cable for the control line, which was only 16 feet long, but the cable path was close to 30. The antenna was finished and in place, in fact, a few weeks prior to getting the entry box mounted. Once I got the coax, ground, and control cables into the garage, I took a break (it was a hot job up there on the roof in the actinic Arizona sunlight) and came back after supper. Fired it up and everything worked like a champ. Worked a guy in Colorado, called it victory, read for an hour, and collapsed into bed. Didn’t get back to the station until the next day.

So late morning I turned everything on, selected 20 meters, and pressed the Tuner button on the front panel of my IC-736.Tink! The rig’s meter needle slammed against the high peg. Whoa. Didn’t do that last night. I tightened all the cables, ran up the ladder to look at the mast setup, and tried again. NFG. I checked the cables for shorts, re-checked all the connections to the ground bus inside the garage, but no joy. I let it set and went back to my office to get some words in on Dreamhealer. That night after supper I went back out there and tried the tuner. Shazam! Everything worked! I didn’t hear much traffic, sunspots being what they weren’t, but the AH-3 tuned my longwire and the IC-736 was happy. I worked a couple of guys and heaved a sigh of relief.

The next day I bopped back into the shack after an hour or two writing, and scanned the bands to see what was live. Heard very little on 20m. Switched to 40. Hit the Tune button. Tink!

I was starting to see a pattern: Works at night. Craps out during the day. Hmm. I opened up the tuner and saw nothing obviously amiss. That said, I had bought the AH-3 in 1992, and it had spent the rest of the 1990s out in the sun, matching my 180′ longwire, lousy ground notwithstanding. It got plenty hot during the day, and I worked plenty of stations all day, irrespective of temperature. Alas, electronics don’t live forever.

I did try a few things. I modified a cardboard moving box into a sunshield and placed it over the tuner so that the bottom of the box faced south and the flaps taped open. The AH-3 was thus shaded entirely but still open to the air. On a whim I put the sensor unit for our wireless thermometer inside the box with the tuner. With the carboard box in place, it worked for a little while longer–maybe another hour–after full sun hit the box. I did a lot of testing and temp recording over the next day and a half. Results: It worked until the air temp hit ~90F. Then, Tink!

Hell, I’ve been a ham now for 46 years. I fix things. I used to fix things for a living, in fact. But at some point I realized that troubleshooting an intermittent 28-year-old tuner was becoming a bad use of my time. Icom had released a newer but compatible tuner ten or twelve years ago. I found a place online selling NOS AH-4s at a discount (Gigaparts in Las Vegas, if you’re interested) and ordered one.

The AH-4 is a little over half the size of the AH-3. I still had to make a custom control cable, but with that done it works like a champ, even in the noonday sun. Granted, it’s not summer here anymore. We’ll see how it performs next June. But in the meantime, I have 75 feet of wire working against a good ground. A guy can do a lot with that alone.

I do intend to get a vertical for the higher bands. The longwire will remain for 40, 80, and 160. (The AH-4 tunes the wire easily on 160. The AH-3 had trouble sometimes, even during the night.) My (not yet purchased) vertical will be ground-mounted close to the ground rod. If I need a few radials I’ll throw them in. At that point the antenna farm will be mostly complete. I have a VHF discone but I also want a 6-meter vertical somewhere, and there’s more thinking to be done about what goes where.

My other ham radio project is still incomplete: An uninterruptible 12V power supply system to run my IC-729 mobile HF rig and shack lighting. With AC power, the panel will draw on a 30A 12V supply I built back in the 1990s. If mains power drops, power will automatically switch to a battery supply of some sort. Near-term, probably gel cells trickle-charged off mains power. Ultimately I want to put a couple of panels up on the roof and buy a husky lithium-ion pack like those sold by Goal Zero. More on that as it happens. It’s the first time I’ve ever used Anderson PowerPole connectors, about which I have mixed feelings. But like everything else in electronics, the journey is the education, and the results are the reward. This time it’s been slow coming together, but better slow than never.

More as it happens.

Monthwander

Feb 3rd, 2019
by Jeff Duntemann.
4 comments

I haven’t been darkening my own doorway here much over the last month. Part of it is an aversion to political posts. The left has made just about everything political in one dimension or another. Topics are not as common as they once were. It was also a quiet January with (thankfully) few crises to report. We spent a considerable amount of time getting ready for The Big Backyard Overhaul, which begins tomorrow. I’ll take some photos and vids of the demolition of our waterfall and our pool, which is having its deep end removed. The waterfall was nothing special: a jumble of mini-boulders in an aggregate of mortar. It looked like somebody dumped a few tons of granite in a pile and then just slopped mortar into the cracks. The boulder pile is there to prevent people from installing a diving board. At least for us, they needn’t have worried. I did all the diving I think I ever want to do in college swim class.

K7JPD is creeping back toward the air so slowly that I’d characterize it as being under the air rather than on the air. I’m still researching compact antennas. In the meantime, I’m going to run a 60-70′ longwire to one of our tall palms, and match it with my Icom AH-3 tuner. I have two very good Icom radios: an IC-729 purchased in 1991, and an IC-736, purchased in 1995. The IC-729 is an odd bird: It was designed to be a mobile HF rig, and it runs off 12VDC. Alas, although smaller than your typical HF rig, I couldn’t conveniently fit it into our minivan, so I built a 30 amp 12V supply and used it on my bench until I bought the 736. Since the 736 arrived, the 729 came out of the box only once a year, for Field Day. I assume it still works, and I’ll find out soon, if not as soon as I had hoped.

The AH-3 is a great tuner. I used it at our North Scottsdale location in the 90s, feeding a 180′ longwire out to the corner of our 2.5 acres. I had a crappy ground there and so the longwire didn’t do as well as other, shorter longwires I’ve had in the past. I really hope the AH-3 still works, because if it doesn’t, there’s a problem: The 729 and the 736 can’t connect to Icom’s newer autotuners. I have a solid manual tuner, but the way the AH3 sits there and clunks around for a few seconds assembling a match when you push the Tune button is borderline uncanny. I suppose I could get a newer radio, but newer radios are basically computers. I stare at computer screens all day. When I operate a radio, I want to handle actual dials, switches and knobs.

Switches, yes. There’s a parallel project to getting my radios back on the air here. I’m building a 12VDC system to power the IC-729, 12VDC LED light strips in the shack, and a few other things that work on 12V. The ultimate goal is to have something like a Goal Zero Yeti backup power unit, on trickle charge from the wall until I can put it on trickle charge from a couple of solar panels. In the meantime, the system will be powered by the 30 amp supply I built for the IC-729 in 1991.

The project involves a DC power control and distribution panel. I’m using PowerWerx fittings and Anderson Powerpole connectors. I’ve never used Powerpoles before. Nothing difficult about them, but it’s a new skill.

And then there’s the AH-3 tuner control cable problem. The tuner came with 16′ 4″ of control cable, and that’s not quite enough to get down off the roof of the shack and into the building far enough to reach the radios. So I have to work up an extension cable in Molex connectors and 4-conductor thermostat wire. I did a little bit of Molex work way back when I was a Xerox tech rep, but that was 40-odd years ago and I’m rusty. So I bought 15′ of 4-conductor thermostat wire at Ace, and ordered something I didn’t think was a thing: a kit of three pairs 4-pin Molex blocks and enough pins/sockets to fill them. I have a crimper, and when I get this posted I’m going out to the garage to make a 15′ extension cable.

A set of four glass dogbone insulators arrived a few days ago, and I have plenty of #18 copper wire. Nothing gets strung, however, until I see what sort of heavy equipment will be hacking up the backyard tomorrow and days following. There’s still plenty of room for things to go wrong, but with a little luck I should have the station back on the air by next weekend.

I get asked “How’s QBit doing?” a lot, and the answer is simply this: miraculously well. He was supposed to be dead five months ago, and yesterday he was still galloping around the backyard with the rest of the Pack while we played dog soccer. Carol has been keeping an eye on his lymph nodes, which seem to be back to their normal size. His appetite is certainly good, and while deaf, he’s otherwise in pretty decent shape for a dog who will be 14 this coming Friday. We don’t know how he beat cancer, if indeed he did beat it. We have our suspicions: Carol custom-makes dog food for all four of them out of ground beef or ground turkey, and vegetables. QBit likes it so much that I think he just told himself, “Like hell I’m going to die, if she’ll give me another bowl of this tomorrow morning!”

He’s just stubborn that way. Wonder who he learned that from.

How to Build a Bentonite Ground System

Apr 16th, 2018
by Jeff Duntemann.
13 comments

Back when Carol and I lived here in the ’90s and early oughts, I had a large lot and a 200-foot wire antenna for the low bands. The antenna didn’t work well…because what I didn’t have was a good ground. Now that we’re back in Arizona, I decided to begin with the ground system, and work up from there toward the antennas.

The problem with Arizona is that it’s dry. No surprise there; in Spanish, Arizona means “dry zone.” At our house on the far north end of the Phoenix metro area, I simply drove an 8′ ground rod into the soil next to my workshop/shack, and clamped a length of #8 solid copper wire to the rod. I figured it would work. It didn’t. The problem (surprise!) was the dry soil, which left the ground rod practically insulated. It was better than nothing, but it certainly couldn’t touch the grounds I’ve had out east, especially the ground I had in Rochester NY. The difference is that I had a swamp at the back of our lot in Rochester, and a climate that delivered rain probably a third of the year. My ground rod was set in soil so wet it was actually mud most of the time that it wasn’t frozen. Tricky to grow vegetables in (our strawberries did well) but man, my Hy-Gain 18 AVT took me around the world.

This time, I did some detailed reading on ground systems, and enlisted the help of Joe Flamini W4BXG, who is a EE and has been licensed longer than I have. I ran the plan past Joe, who approved. This past Saturday, I finished it.

So. The basic idea is to increase the conductive area of a ground rod, so that it connects to a greater area than the area of a 5/8″ diameter rod. From a height, you do this:

  • Dig a round hole.
  • Drive the ground rod down into the soil at the center of the bottom of the hole.
  • Put a length of PVC pipe in which you’ve drilled a large number of holes into the hole beside the ground rod.
  • Fill the hole with sodium bentonite clay, moistened with an ionic solution like Epsom salts.
  • Keep the bentonite and the soil around it a little damp. (This is what the hole-y pipe is for.)

Now let’s go through what I did in detail.

I had our landscape company bring out an earth auger. I expected something a little smaller, having looked around at tool rental firms. This one had a 12″ auger 48″ long. It took just 15 minutes, and I was glad I didn’t have to control the monster myself.

Drilling the Hole - 500 Wide.jpg

Earth augers are not tidy things. In fact, the hardest single part of the project was using an improvised scoop on a long handle to get the last of the loose dirt out of the bottom of the hole. Nor was the hole completely straight. Still, it was straight enough.

Next, I took the ground rod and used my bench grinder to sharpen its point:

Ground Rod - 500 Wide.jpg

I then used steel wool to brighten the copper the full length of the rod. This makes it more conductive, which is the whole idea. Having brought it to a nice bright polish, I took out my five-pound sledge and drove the rod into the center of the hole. I had previously bought a 4′ length of threaded 1/2″ schedule 80 PVC pipe, and drilled holes every inch down the full length of the pipe. Each drill pass cut two holes, giving me two rows of holes on opposite sides of the pipe. I put PVC caps on both ends, and positioned the pipe in the hole with an artfully bent coat hanger.

Moistener Pipe - 300 Wide.jpgI had done the math on the volume of the hole and the density of bentonite clay, and calculated that I would need four 50-pound bags of bentonite powder. I bought it from a drilling supplies firm on the west side, for $8 a bag. (Bentonite has many uses, and one common use is borehole mud.) Some people mix a bentonite slurry in a wheelbarrow and then tip the slurry into the hole, but I didn’t have a wheelbarrow. What I did is fill the hole by pouring in a layer (3″ or so) of bentonite powder, and then wetting it with water in which I had dissolved ten pounds of Epsom salts. I stirred the goop a little with a metal rod to make sure all the powder got wet.

I repeated this layering process until the hole was full. Miraculously, my 200 pounds of bentonite clay powder filled the hole to within 2″ of the rim. Enough, and none left over. (Math works!) Once I filled the hole and wet the top layer down, I forced water into the moistener pipe with a pressure nozzle, taking advantage of Phoenix’s relatively high water pressure. The idea is to make sure that all of the powder becomes mud.

A few notes on bentonite powder: It’s as fine as talcum powder, and blew around in Saturday’s unfortunate wind while I poured it. I wore a mask to keep from inhaling it. When wet, it becomes a slippery, slimy-feeling mess that clings to everything it touches. I was very glad I didn’t try to mix a slurry outside the hole. Bentonite gloms onto water, and over time, the clay in the hole will become uniformly damp. I’ll sprinkle the hole with the garden hose periodically, and pour some additional Epsom salts solution into the moistener pipe.

Pouring the Bentonite - 500 Wide.jpg

I’ve been soaking it each day, not only the bentonite but also the soil around it. Bentonite expands slightly when wet, and will force itself into all the tiny voids in the interface between the soil and the bentonite fill. In my neighborhood we have the advantage (for ground systems at least) of a septic system, which distributes a different sort of ion solution into the soil. I’m expecting far better soil conductivity here than we ever had in our ’90s house.

That’s pretty much it. I have no antennas mounted yet, so I can’t test it for the time being. No problem; once I have my feed-throughs in place, I’ll run a length of wire up to one of the palm trees, and see how well my IC-736 loads. Jim Strickland suggested building a simple crystal radio using a germanium diode, of which I have many in the drawer. Crystal sets are very dependent on a good ground, as I discovered in my distant youth. If I can bring in local AM stations well, I’ll consider the ground a success. The ultimate goal is to get a ground-mounted trap vertical, like the 18-AVT or similar. In the meantime, I know how to get a lot out of 75′ of copper wire worked against a good ground.

And now, for the first time in a fair number of years, I have a good ground!

LED Strips for Workshop Lighting

Feb 21st, 2018
by Jeff Duntemann.
12 comments

60W Bulb Wafer - 500 wide.jpg

We replaced nearly all of the incadescent bulbs in the house with LED bulbs shortly after we bought it in late summer 2015. That came to 27 60W bulbs and ten or twelve 75W floods for ceiling can lights. You can’t get incandescent bulbs in the commoner sizes anymore, and the power savings is considerable. LED bulbs have come a long way in the last few years, and the “softer” light quality levels (3000K and below, most of which were 2700K for us) approximate incandescent light close enough for what we do.

There are a couple of issues with LED bulbs. We bought Feit bulbs in bulk when we re-bulbed all the ceiling fan lights. Two years on, and the Feit bulbs are dropping like flies. I have nine dead but intact Feit 60-watters on my workbench, and two more that I dismantled to see what’s in them. What’s in them isn’t much: A voltage doubler/rectifier board that converts 117VAC to 236 VDC. There’s a disk holding nine LEDs, with two wires down to the power supply. The photo above shows what it looks like when you hacksaw the plastic globe off a Feit 60W equivalent LED bulb. It’s unclear to me whether the nine LEDs are single diodes or blocks of several fabricated together. It seems like a stretch to put 26 volts on a single LED and not see it emit plastic instead of light.

I’ve been taking bulbs apart to try and see why the Feit bulbs die so young. I’ve pulled two apart: One had a bad power supply. The other had a bad wafer. The wafer, however, was intermittent: Tap it with a screwdriver and it flickers, and sometimes comes up to full brightness. The dead power supply was just dead, without any indication of why. It stayed dead when tapped, unlike the intermittent wafer. Cheap crappy manufacturing, I’d guess. This is one Feit I will gladly walk away from.

LED lighting is problematic in ham radio work because of the broadband noise generated by the bulb power supplies. Fluorescent tubes have the same general problem. My notion is to create a separate lighting system in my workshop/ham station using LED lamps run straight-on at 12VDC. I had hoped that the wafers ran at 12VDC or 24VDC, so that I could harvest them from bulbs with failed power supplies. Not an option.

So I started sniffing around to see what sort of lamps are available for 12VDC. I bought a couple at a hamfest to play around with, and talked to the techs at a lighting store up in Kierland. They had an interesting display: Assemble-it-yourself LED strip lights. These consist of an anodized aluminum U-channel, with a self-adhesive strip of LEDs stuck to the bottom of the channel, with a linear plastic lens that snaps into the U-channel. The LED strips take 12VDC, and use 2.88W per foot.

LEDTapePackage - 500 wide.jpg

The LED tape strips come on a reel, with 16.4 feet on the reel and 3 LEDs per inch. The reel isn’t cheap; I paid $235 for it, and that’s about what they go for on Amazon. What I did was buy an 8′ section of channel/lens and put down just under 8′ of LED strip. The strips have clearly marked points every inch where you can cut them with an ordinary scissors, leaving solder pads on each side of the cut.

LEDTapeCloseup-500 Wide.jpg

The strip comes with a .215″ female barrel connector on the end of 6′ of 2-conductor cord. But again, there are solder pads every inch, so you can wire them to a power source any way you want to. What I did (at least for testing) is dig around in my Big Box o’ Wall Warts and found a Dell APAC-1 power supply, which came with a Dell matrix printer someone gave me ten or twelve years ago. It’s labeled for 12VDC @ 2A, and the strip draws 1.92A, so the supply is working pretty hard. (It squeals, way up there where Carol can hear it and I can’t.)

What I did with the strip is mount the four clips that came with the U-channel under the front edge of the first shelf above my workbench, and then clipped the U-channel to the shelf. The lower surface of the shelf is 11″ above the bench, so I’d have to do some bending and stooping to actually see the LEDs. And the intensity of the light is marvelous, shining down right where I do the sort of close work that electronics requires, which these days is real damned close.

Illimuminated Bench - 500 Wide.jpg

Because the light comes from a strip of 288 LEDs, there are basically no shadows anywhere under the strip, unless you completely block the light. This means that you can work in good light without worrying as much about your hands casting shadows on what you’re doing. It’s almost like the project photos in old QSTs, where all parts of a complicated hand-wired chassis are completely illuminated. The photo below is of a high-voltage power supply placed on the bench beneath the LED strip, and is literally what you’d see were you sitting at the bench poking at the supply.

Lit Chassis - 500 wide.jpg

This was only a first step. The strip won’t be powered by the APAC-1 long-term. I have a 30A 12VDC supply that I built out of an old minicomputer power supply somebody gave me. That will be the power source for all the lighting in my workshop/shack once the whole system is complete. I’m looking into overhead lighting now, and may simply use the remaining 8′ of LED strip on the reel with a white diffuser lens, clipped to the drywall ceiling.

Ultimately I want to work up a solar panel system on the roof of the garage, charging a 12V battery of some sort to supply lights and radios. The landscapers are going to auger a hole next to the shack for an engineered ground system tomorrow morning, so I have other work to do before I get on the air. It was a fun project, and will make working on projects a great deal easier. Good light is not optional!

Shoveling Heavy Metal

Apr 25th, 2016
by Jeff Duntemann.
1 comment

I literally didn’t know that it was Earth Day until the metal recycler guy thrust a bright green T-shirt in my hands. I had just sold them $77 worth of metal, and on Earth Day they were giving away T-shirts. He invited us to stay for their free Earth Day barbecue, but I had to decline: I was still shoveling.

I missed Earth Day mostly because I was shoveling. That morning I had shoveled close to 300 pounds of metal into the back of the Durango. About 30 pounds of that was bronze and copper, and another 100 or so was aluminum. The rest was iron and steel.

My scrap metal collection is legendary; why did I let so much of it get away? Easy: I dumped the stuff that wasn’t likely to be useful. Chunks of pure copper don’t machine well. Brass is way better–I wasn’t giving away any brass. The bronze was a sort of special case. Carol’s dad had given me several husky bronze Acme-threaded bearing brackets that once gripped a lead screw from some very large but long-dead surface grinder. Each one was bigger than my fist. I’d been staring at them (and carting them from state to state) since the early 1980s, and never came up with a use for them. In the cause of The Duntemann Ensmallening, I decided to trade them in for something much more useful: cash.

Ditto the aluminum, most of which consisted of aluminum grinding wheels from very large but (probably) long-dead surface grinders. The largest were 24″ in diameter and 5/8″ thick. All had once had a coating of fine diamond abrasive on their edges, suitable for the grinding of carbide dies, which was what Carol’s dad did for a living. When the diamond coating got thin at any spot along the edge, the wheel was swapped out for a new one and scrapped.

He gave me a lot of them.

I did keep a few, and I have used a couple in the last 35 years, especially the smaller, 8″ diameter ones. The rest of the aluminum pile was odd stuff I’d picked up cheap at hamfests in the 42 years I’ve been going to hamfests. As for the steel, well, it consisted of odd and generally rusty chunks that used to be frames for chairs, lamp base weights, a beat-to-hell surface plate, and several 3′ lengths of badly galvanized (and now corroding) 1″ threaded rod that I no longer remember obtaining at all. 1″ threaded rod is stock at Artie’s Ace Hardware in Phoenix, and I don’t have to scrub the rust off of theirs. Out it went.

I’m probably due for another Advil. There’s a hard deadline for emptying the garage utterly: On May 4 the jackhammers will show up to take out our crumbling garage slab. Much of what I will be doing between now and then will be shoveling. Tomorrow I’ll shovel a load of ancient computers, computer accessories, dead cordless phones, ratty computer speakers, and cables (RCA / VGA / parallel etc) into the car to take up to Best Buy for recycling. I still have to Craigslist my small workbench and figure out how to con somebody into taking a middling list of dead or limping radio gear, including my Kenwood TS-520S (blew out its balanced modulator) a WWII Navy MAB receiver, condition unknown, and a Heathkit HW-22A that’s immaculate but may or may not work. (I bought it cheap at an estate sale, sans cables.) Most regretted may be my Hammarlund HQ-145X general-coverage receiver, which was my SWL radio in college and later my Novice receiver. It always had a few quirks, and probably has a couple of bad tubes, as it doesn’t bring much in anymore. (I haven’t had it opened up in 30 years or so.) Alas, the Hammarlund is enormous, and does nothing that my IC-736 doesn’t already do, in a third the space. I’ll miss it, I guess. But that’s what an Ensmallening is all about.

I’m going to ask $75 for the whole pile and see what happens. I could probably have gotten more for them by selling each item individually, but it would be a bad use of my time, considering all the shoveling that still has to be done.

I may try to foist a few things off on my hapless partygoers at our nerd party next Saturday. We still have a Midcentury Modern steel stepstool, decorated with drips of every color known to Sherwin Williams, and a “flying saucer” charcoal grill from the ’50s. Beyond that, what’s left is lumber scraps and useless crap that’s going out on the curb this Wednesday, if I can force myself to keep shoveling.

No ifs. Shovel I must, and shovel I will, until the Ensmallening is done.

LED Bulbs, RF Noise, and a Crazy Idea

Mar 13th, 2016
by Jeff Duntemann.
20 comments

Carol and I were in Costco last week, stocking up on consumables (everything from toilet paper to Hoody’s Peanuts) when we spotted something that made me do a double-take: a package of four Feit LED dimmable 60W equivalent light bulbs for $10. I’ve never seen them for less than twice that. We grabbed a pack to try at home, because our new house here contains a lot of 60W bulbs.

How much of a lot? There are nine Hampton Bay ceiling fan/lamp fixtures, each holding three 60W bulbs. (We found later that the fixture over the dining room table had three 75s in it.) That’s 27 bulbs right there, plus another twelve or fifteen in bathrooms and outside light fixtures. Figuring 40 60W bulbs, that’s 2,400 watts. Granted, not all of them are on at once, and several fixtures (like the one in the guest room and the two outside on the patio) are rarely on at all. However, there are another eighteen 65W ceiling floods, so I’m guessing our typical evening use is about 2,500 watts overall. It adds up. If bulbs are now as cheap as Costco was offering them, I was ready to jump.

A sidenote: There was some sort of utility company instant rebate, so the register price was about 1/3 less than the package price. Outside the Phoenix area, your prices may (and almost certainly will) vary.

This being Arizona, there was a thick layer of brown dust (over and above the dead bugs) on the lamp globes and on the existing bulbs themselves. We ran three loads of lamp globes through the dishwasher because their spatter finish tears threads off the ScotchBrite pad by the sink. I put three bulbs in the fixture in Carol’s office, then stood back to gauge the quality of the light.

Marvelous! Three $2.50 LED bulbs gave brighter and slightly whiter light for a total power draw of 28.5 watts. We went back to Costco and bought 24 more, plus a test pack of 65W equivalent LED ceiling floods. I spent a day on a ladder swapping out bulbs, and although the ceiling floods aren’t all done yet, we’re looking to cut our lighting power draw to 1/6 of what it would be on incandescents.

This isn’t all about money. It gets hot in Phoenix in the summer (duhh!) and the heat that you pay for when you light your bulbs you then have to pay to pump out of your house with the AC. Ok, so maybe it is all about money. In some respects, LED bulbs are a twofer.

Now, there’s a downside. Both CFL and LED bulbs require power at entirely different voltages than incandescent lamps. Every bulb has a little power supply in it, and to keep the power supply circuitry small, the supply uses a technology that generates a lot of RF noise. If the whole house is running LED bulbs, I’m guessing that my IC736 will deliver audio that sounds like the center of a raging thunderstorm, only 24/7. I don’t have my shack wired up yet, but it’ll be interesting to see what happens when I run a temporary longwire out to the pool shed later this year.

Now, it won’t happen this year and perhaps not next year, but the 5-year plan includes a new building in the NW corner of our 5/8 acre lot to house my workshop and radio shack. (I’m using the small garage for now, and although I was clever and got everything in, it’s…cramped.) I’m sure I’ll hear our LED bulb symphony (and perhaps the neighbors’) but if I don’t use LEDs or CFLs in the shack, things may be a lot better.

So…what are the chances of opening up the bulbs, pulling out or bypassing the power supplies, and running them at the LEDs’ native voltage? This isn’t an idea original with me, and in fact one chap has a very nice article up on Instructables. The 40W bulb he dissected delivers 30VDC to its LED array, and he had to do some major surgery to rewire the array to take 12VDC instead. My approach would be to figure out what DC voltage a given type of bulb generates for its LEDs, and then build a high-current passive (i.e., non-switching) power supply to deliver exactly that voltage to all the modded bulbs in the building. (Note that there’s nothing magical or standard about his 30V figure. That’s just what the maufacturer happened to use in that particular model of bulb.) This would require running a separate 30VDC (or whatever) power network inside the workshop building, but since it’s going to be a custom building, I can do that.

We’re not nearly done with the house and landscaping here yet, and I won’t have a great deal of loose time until the summer. (We still have work to do on our Colorado house before we sell it.) I’ll start a research binder on LED bulbs in the meantime, and maybe allow myself a few hours at some point to pull a cheap bulb apart to see what its LEDs are eating. If any of you have played around with LED bulb internals, (or have come across any pertinent links) by all means share in the comments. I have a hunch that a lot of very clever guys are pondering this problem right now, and I’m looking forward to hacking the hardware myself. I haven’t done much building in the last couple of years for various reasons, and damn, I miss it!

Odd Lots

Feb 18th, 2016
by Jeff Duntemann.
12 comments
  • Lazarus 1.6 has been released. It was built with FreePascal 3.0.0, a first for Lazarus. Mostly incremental changes, but there’s a new rev of the docked form editor that looks promising, even though it’s not quite stable yet. Wish I had more time to play with it!
  • Older versions of Lazarus have run well on the Raspberry Pi for me. However, installation on the newer Raspberry Pi 2 is much trickier. This installation tutorial is almost a year old, and I haven’t yet installed Lazarus 1.4 or 1.6 on my Pi 2, but it’s the best how-to I’ve yet seen.
  • From Glenn Reynolds: Indie author Chris Nuttall lays out his journey as an indie, emphasizing that all but the biggest names are being driven to indie by publishers who simply don’t understand which way the wind is blowing. Read The Whole Thing, as Glenn says.
  • Back when I reviewed the Baofeng handhelds, there was some discussion in the comments about the RDA-1846S SDR chip. Gary Frerking pointed me to the HamShield project on Kickstarter, which is an Arduino add-on board (a shield, in their jargon) that uses the RDA-1846S to transceive on 2M, 220 MHz, and 450 MHz. Like the Baofeng radios, HamShield will also operate on FRS, MURS, and GMRS, though the group doesn’t say that explicitly. (This is an SDR, after all.) It’s not shipping yet, but they’ve raised a fair amount of money (well over $100,000) and appear to be making progress. Definitely one to watch.
  • Cool radio stuff is in the wind these days. One of Esther Schindler’s Facebook posts led me to Beartooth, which is an SDR roughly similar to HamShield built into a smartphone battery case that snaps onto the back of your phone. Unlike HamShield, beartooth is going for FCC type acceptance and will operate on MURS. However, there’s been no activity on their Web site since mid-December and I wonder if they’re still in business. It’s not an easy hack; see this discussion from midlate 2014.
  • Oh, and I remembered GoTenna, which is similar to Beartooth except that it’s limited to texts and geolocation data. (That is, no voice.) It’s a Bluetooth-powered stick that hangs on your belt and uses your smartphone as a UI, basically, and allows you to text your hiking buddies while you’re out beyond the range of cell networks. I guess that makes it a sort of HT…a Hikey-Textie. Unlike HamShield and Beartooth, GoTenna is shipping and you can get two for $300.
  • Twitter continues to kill itself slowly by shadowbanning users for political reasons. What the hell is in it for them? When they collapse, something else will appear to take their place. They’re a tool. (Take it any or every way you want.) When a tool breaks, I get another tool, and generally a better one.
  • In case you’ve never heard of shadowbanning…
  • I stumbled on something called Roblox, which is evidently a high(er) res take on the Minecraft concept. It’s looking more and more like what I was thinking about when I wrote my “RAD Mars” piece for the last issue of Visual Developer Magazine in late 1999. Anybody here use it? Any reactions?
  • Slowly but steadily, reviews are coming in on my Kindle ebooks. Here’s one that I particularly liked.
  • The Obamacare exchange in Colorado “smelled wrong,” so Carol and I avoided it. We were right. (Thanks to Sarah Hoyt for the link.)
  • I don’t care how many tablets and smartphones you have. Paper is not dead.

Odd Lots

Sep 15th, 2015
by Jeff Duntemann.
2 comments
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