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LED Bulbs, RF Noise, and a Crazy Idea

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

  • 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

Odd Lots

Odd Lots

Odd Lots

Odd Lots

Review: The Impossible Baofeng HTs

3 HTs - 500 Wide.jpg

I bought my first ham radio handheld (“handied-talkie” or HT) back in 1977. The Standard Radio SR-C146 had five crystal-controlled channels and weighed two pounds. (No wonder they called it a “brick.”) No TT pad, no CTCSS. I don’t recall what I paid for it new, but I’m thinking $350–and that didn’t even include a charger. (I built a charger for it from scratch!) That would be about $1400 today. It was a really big deal, and I used it for almost ten years, until I bought an Icom HT at Dayton in 1986.

In truth, I never used HTs all that much except at hamfests. I’ve had 2M mobiles in various cars, and for the past 18 years or so have used an Alinco mobile rig as a base. I still have the Icom in a box somewhere, but the case is cracked and it’s been in the corner of my mind to get a new HT for almost ten years.

Then Bob Fegert mentioned the Baofeng dual-band UV-82 HT, which now sells on Amazon for $37 brand new. (I actually paid $35.) In 1977 dollars, that would have been…ten bucks. So I ordered one. While cruising the Web looking at reviews and commentary on the unit, I happened upon the Baofeng BF-888S. Amazon had those for $15. $3.85 in 1977 funds. So I bought one of those as well, just to see what a $15 HT could do.

Both radios put out 1W or 4W selectable. The UV-82 covers the 2M and 70cm bands. The BF-888S covers only the 70cm band. Well, actually not only the ham bands, which is an issue worth a little discussion here. Many commenters on the ham boards loathe these radios, for a simple reason: They claim the ham radio positioning is only a ruse, to get around FCC type acceptance.

The problem is that for use on the several business bands, the Family Radio Service (FRS), the General Mobile Radio Service (GMRS) and the Multi-Use Radio Service (MURS), a transceiver must meet certain FCC requirements and pass tests to ensure that it meets those requirements. This is called type acceptance. A type-accepted radio will transmit only where its type acceptance allows. There are other requirements that aren’t about frequency. FRS radios, for example, may not have removable antennas. Ham radio gear, on the other hand, does not require FCC type acceptance at all.

These are software-defined radios. Within a broad band of frequencies dictated by the output power amp, they can receive or transmit anywhere you want them to. A free program called CHIRP allows you to create a special-purpose database of frequencies and other settings, save it as a file, and then squirt it into the radio through a USB cable. It’s nominally illegal to use a radio like the BF-888S on FRS or GMRS, but a quick Web scan shows that it’s evidently done quite a bit. The type acceptance process takes time and money, so a radio pitched for amateur use can cost less.

The flexibility of using CHIRP to set frequencies and settings allows these radios to also act as scanners and receive public safety and weather channels. It’s possible to disable transmit on any frequency, which I did for the weather channels. (One of the downsides of the display-less BF-888S is that it’s not always obvious what frequency you’re tuned to. Mistakes are possible, and in this case may be rule violations that may cause interference.)

As 2M and 70cm radios, they’re pretty good. I can hit all the repeaters I usually reach from here, just using the “rubber duckie” antennas. Audio is clean and strong. The UV-82 has a better receiver: Weak local signals will break squelch on the UV-82 when they won’t budge the BF-888S.

There are some downsides:

  • Neither radio has a squelch knob. Squelch levels are parameters that you set from the keypad (for the UV-82) or in CHIRP. This can be annoying if your noise level rises and falls for some reason, or if a weak signal is right on the edge of squelch. (The BF-888S has a button that turns squelch off while pressed, which is better than nothing.)
  • The chargers are flimsy and almost weightless. I’m not sanguine about how long they’ll last, and they certainly aren’t physically stable. Nor are the chargers or charge voltages the same for the two radios.
  • The antenna connectors are SMAs. I had to order some SMT-UHF adapters so that I could use my discone antenna up in the attic.
  • Both radios “speak” a channel number when you move up or down the channel set. With the BF-888S this is the only reliable way to know where you’re sitting, as the numbers on the channel select knob are almost invisible.
  • The UV-82 has a broadcast FM radio feature, which works fairly well but is not easy to use, especially if you switch stations a lot. (It is a little weird hearing classical music coming out of a ham radio HT.)
  • Although it would be very useful, I don’t think it’s possible to control (rather than simply program) either radio through the USB cable.

Both radios have white LED flashlights built-in, for what it’s worth.

So. I’m sure a Yaesu or an Icom HT would be better in a great many ways. However, Icom HTs don’t cost $35. Given how little I use HTs, the price was irresistable. How well they will serve over time is an open question. They seem rugged enough to withstand a certain amount of outdoor rough-and-tumble. If they break (or if anything weird happens) I’ll certainly tell you here.

So far, recommended.

Odd Lots

Odd Lots