Y’alls on crack.

image

I bought some Lite-On led displays with integrated shift register driver a few years back. They’re kinda cool, reducing the microcontroller pin count needed to drive two digits of alphanumeric displays to a mere three — chip select/enable, clock, data in. Not bad at all, even if they don’t have serial out like a proper shift register; the last cell of the shift register is connected to output latch to remove the need to externally fire the latch.

But good luck reading that datasheet.

image

So far so good, right?

image

aargh.

image

AAAUGH. WHY?! WHHHHYYYYY??!!! All this is missing is a liberal use of Comic Sans.

Please, do not do this.

GE Orion VCO adjustment / alignment for band changes

What you’ll need: Multimeter, dummy load, Orion programming software OrionVCOs(Programmer for Windows or the older DOS software), radio code files for the radio (used when programming; re-uploaded each time the flash memory fills up).

If you are moving the band split (and this is probably why you are here), you also need the SC or SC4 files.

Full instructions follow this silliness…

Read more “GE Orion VCO adjustment / alignment for band changes”

The Westinghouse Prog Stom Ass’y, or Lost Arts in Electronics

IMAG2765…You read that right, the module has an ancient TYPO on it.

Today I was at the Miami-Dade County Store, and somewhere in the shelves of weird old broken network hardware and PCs that had been picked clean by creepy Jamaican exporters, this one bronze colored anodized aluminum mystery box peeked out at me. The thing just had a strange energy about it, I couldn’t really explain it.

This box has silently served hundreds of thousands of people on their way to work, to play, in good times and bad. But what is it? And what’s with the typo?

Read more “The Westinghouse Prog Stom Ass’y, or Lost Arts in Electronics”

Mac OS X is beating your hard drives to death. Here’s the fix.

You read that right.

Quick link to the fix before I get to my usual rambling: hdapm. Install it and it will automatically set itself to auto-start on each boot and disable the auto park feature for all your drives.

Under Linux you can also use the hdparm command. Please note that you still need to fix your Mac OS X system with hdapm though as it will by default reset the power management on each boot!!
hdparm -B 255 [device]
or, if that throws an error
hdparm -B 254 [device]

device is usually /dev/sda.

My usual rambling as to the background on this problem follows…. 🙂
Read more “Mac OS X is beating your hard drives to death. Here’s the fix.”

Replacement for the L603C

Cockus Blockus. :(
DENIED!!!

At left: The very common ULN2803; picture borrowed from Adafruit Industries, who sell them for $1.95 a pop.

The Harris Z16HD+ transmitter at work has a bunch of these STMicro L603C Darlington arrays all over in weird places where Harris decided to run things unnecessarily off the +50-60V PA power supplies.

Original part datasheet: L603C
T
he L603C’s max voltage is 90V.

The only replacement I have found so far that has a suitably high voltage rating: SG2823J. SG2800 series (SG2823)

It’s $65 a piece at Digi-Key!

At this point the question can be raised of “how much is that piece of equipment REALLY worth to you?”. If you need to replace an L603C that is used in a lower voltage application (voltages below 50V), the common, inexpensive ULN2803 is your chip! (See link above.) If you need that high voltage, though, prepare to open your wallet a bit wider than usual…

The awful tale of the spiral CFL

Ladies and gentlemen, here is an awful story about light bulbs and why they now SUCK.

In the early 1900s, we had incandescent bulbs with carbon filaments, then tungsten filaments. The earliest bulbs were very low brightness and could only be pushed to burn a sort of orange color at very low efficiency. As time and technology advanced, incandescent bulbs became more and more efficient. In general, the hotter you burn the filament, the more efficient the bulb. Since the bulb is emitting light as a black-body radiator, the visual quality of the light increases with higher filament temperatures as well. Larger wattage bulbs produce more lumens per watt than smaller ones.

The halogen bulb, which dates all the way back to the earliest efforts to prevent the glass from becoming darkened from evaporated filament material on the earliest bulbs, was found to work really well if pushed to super high temperatures using quartz as an envelope material instead of typical sodalime glass. Iodine is used inside the bulb as a cleaning agent; once the quartz envelope and filament reach typical operating temperature, the iodine scavenges the evaporated tungsten back off of the quartz. Pretty cool, really. Of course since these bulbs run so hot, it’s easier to squeeze better efficiency ratings out of them!

So we have those two coiled filament brothers… They’re simple resistive loads, easy to manufacture using no hazardous materials, and they just work. Well, ’till they don’t… then you just change it out, inexpensively.

The problem with them is that they generate a LOT of waste heat, and result in very high energy consumption. As energy shortages become problematic in modern urban areas, and the pollution and other effects from generating this energy using fossil fuels or old nasty-ass nuclear power technologies from the 1970s (I’ll yell about this in another post!) become troublesome, the desire became strong for much higher efficiencies.

Enter the discharge lamp.

The first very high intensity discharge lamps were carbon arc. These predated even the incandescent bulb. They operated in open air using two carbon rods which were slowly consumed as the lamp operated, requiring a regulating mechanism to keep feeding fresh carbon. Some of these lamp regulators are truly beautiful and clever clockwork! They were practical for street lighting and lighting large building spaces, but never made it into the home. Fire hazards? Oh, you betcha. 😉

The carbon arc lamp may still be found in some applications including spotlights that are aimed into the sky. It provides a very harsh, bright light.

Later, in the early 1900s, there were efforts made to use discharge across a low pressure gas inside a glass tube for lighting. Different gases or mixes of gases were used. They all required some pretty scary voltages to strike the arc (3-15 kilovolts depending on gas type and arc length). Daniel McFarlan Moore invented an early practical lamp using carbon dioxide for a nice daylight color, which was used for photographic and color matching applications for some time.

The mercury vapor lamp had been around since the early 1900s as well, but it produced a nasty blue-green light and was not really pleasant for indoor lighting use. In the 1930s, General Electric started lining mercury vapor tubes with phosphor to correct the color and provide enhanced light production, and the modern fluorescent lamp was born.

It flickered, of course. The magnetic ballast transformers needed to regulate the current to the lamp all just feed it 60 cycle AC current.

The fluorescent lamp was introduced to the public at the World’s Fair and Golden Gate Exposition, and it wound up in millions of homes and businesses. The classic fluorescent lamp is a linear tube, and requires fixtures shaped to hold it. Probably the most common form is a 48 inch long form factor that’s available as a 30 or 40 watt lamp. Higher efficiencies are possible in thinner bulbs.

Color rendering was, and still is, fairly awful. There are bands of color simply missing from the lamp’s output. Ott-Lite has some tubes that are reasonably better, through the addition of more exotic and expensive phosphors, but for some reason nobody else ever caught onto the idea that people actually see in color.

Efforts to get away from the long straight tubes have included the “Circline” lamp which is an almost closed C shape with a plastic bracket/connecting plug occupying the space between the ends, and the U-bend tube.

Lights of America used to produce screw in adaptors that worked well in a lot of table and ceiling lamps. They contained a small ballast inside a bracket that screwed into the socket, and had a T-shaped holder that clipped to a Circline bulb and held it in place. To install it in a table lamp, you would remove the shade, unclip the harp (for some reason knowledge of what this is called is uncommon!) from its bracket near the socket, screw in the adaptor, reinstall the harp, put the tube on the arms, and put the shade back on.

This could have been, technically, the first compact flourescent to gain widespread market in the US.

Old_compact_fluorescent_lampPhillips and some other companies also had screw in self-ballasted CFLs. They usually used a magnetic ballast – a very heavy transformer, and would knock over your table lamp. In addition, the magnetic ballast fed the lamp 60 cycle AC current which made it prone to visible flicker.

The electronic ballast eventually showed up, resolving the flicker problem, but also adding a bonus side order of radio/tv interference problems in some designs.

In the late 1990s, Enron put California’s balls in a vise. Through creative accounting and generating more artificial energy shortages than actual energy, they got people used to rolling blackouts and the need for extreme conservation measures. We looked at the incandescent lamp again and realized it was time to ditch it for the higher efficiency of flourescent. LED lighting was out there, but it wasn’t ready for prime time; the first practical white LEDs were just barely enough for a flashlight.

The PL type flourescent lamp, basically a super compact version of the U-bend bulb, finally got paired to a miniaturized screw in miniature electronic ballast and produced as the first modern style CFL in the late 1990s. They were kind of an expensive curiosity at the time and faced with lots of technical difficulties. First off, this represented the first time in US history that manufacture of light bulbs jumped completely offshore to China.

American electronics manufacturing had been so heavily offshored at this point that nobody was ready to manufacture the electronic ballasts stateside. A small but growing number of brands of Chinese imported CFLs became available, and they were all… okay. They had build quality problems, were prone to detonating and filling a room with smoke and/or causing fires, and NONE could be run in a totally enclosed fixture because the ballasts got too hot.

Interestingly, the worst CFLs I have ever seen came out around this time: the GE Biax. The GE name wound up being associated with these either because GE bought production runs from a Chinese manufacturer to have them custom branded for them, or simply because they licensed their brand name and trade dress to an importer or retailers to place on Chinese bulbs themselves. The Biax, however, managed to be prone to downright malevolent failure. The bulbs would be unusually dim and difficult to start from day one, which would indicate either a bad tube or problems with the ballast. By day four or five, the bulb would be flickering or dead, and when they died they tended to fail catastrophically with the ballast area catching fire and breaking open.

If you look at these early CFLs they all had the same sort of appearance. They had a series of U-bend tubes coming out of the base, usually with thin pips connecting them together. They were made in the same molds and machines that were used for “PL” size fluorescent tubes. This form factor was chosen as a compromise between good performance and compact size. Some light is lost in a PL bulb where the light from one tube simply gets absorbed into the phosphor on an adjacent tube, but it really wasn’t half bad. Some of these tubes were even made with really good “daylight” color.

AND THEN THE STUPIDITY HAPPENED.

The spiral fluorescent lamp was experimented with by General Electric in the 1970s. At the time, they shelved it because they could not figure out how to adapt it to mechanized manufacturing. It did not look like the modern spiral CFL; it was a much more widely spaced tube to avoid the occlusion problem wherein the turns of the spiral block light output.

The Chinese took a look at this design and figured it’d work right into their marketing strategy. See, the way I’ve analyzed it, and feel free to laugh at me if I’m wrong, is that the Chinese really love to make themselves spaces to sell on the American market by using technologies adapted or outright stolen from elsewhere, then mass producing a product that may be of inferior quality, but has a lot of flashy features added to entice the consumer to buy theirs through simple comparison shopping. “But does the American made washing machine have Bluetooth and a bunch of LEDs all over it and play a song when it’s finished? No? Okay, let’s buy the Chinese one that does.”

In China, labor standards and employee compensation are NOT what they are over here, so cheap human labor is often sought over safer but more expensive production methods.

Remember how I said the spiral bulb didn’t lend itself well to mechanical production?

Well, Shanghai Xiangshan saw the spiral lamp and decided to enter mass production… employing dozens of glassblowers to manufacture the bulbs. Very soon afterwards, the glassblowers began to fall horribly ill from exposure to the mercury used in the bulbs.

Problem? Your glassblowers are all dying of mercury exposure.

Solution? Sweep it under the rug with a big iron broom. CAPITALISM!!!!!

wpid-imag2307.jpg
Pissbulb shortly after powering on.

Now, remember how I said the Chinese really like to get consumers drunk on flashy but useless features? The spiral bulbs, looking like soft-serve ice cream dispensed into a cup, did indeed have a “wow” factor about them…. Followed soon afterwards by a “yuck!” factor because the quality of light from these bulbs
is
simply
AWFUL.

The cheapest, nastiest phosphors were used shortly into the production runs, owing to the wonderful Chinese business core ‘value’ of quality fade. They look like someone took a piss on the bulb. Additionally, the quality of phosphor coating inside the handblown glass tube is extremely variable, and it’s not uncommon to have large dark spots where the phosphor is too thin or too thick. Just eyeballing one on my desk here, I’d say that about 50% of the light, if not more, gets fired into a useless space inside the spiral where it doesn’t escape, or into adjacent turns of the tube.

Then the clever, evil marketing showed up. The spiral bulbs were foisted upon the public as being the best new thing, just because they were new and looked cool and unique! Nevermind that a U-bend type CFL of the same wattage, placed alongside the spiral, would show just how pathetic the light output and performance of the spiral is.

Flash forward to today… you cannot find the U-bend CFLs anymore. They have reached near industrial extinction in favor of the “ice cream whip” spiral bulb. Only a few special application high wattage CFLs still maintain the old, more efficient, mechanically produced tubes that didn’t require a glassblower to slowly poison themselves to manufacture it.

It’s the horrible end of a vicious cycle that will be very difficult for the industry to ever pull itself out of.

Fortunately, the LED bulb has become practical and is now technically superior. The CFL’s only remaining advantage is that it can be cranked out cheap as hell.

Do the entire world a favor and buy LED instead.

Radio Shack has lost it…

image

What you are looking at is the prime endcap space in the middle of my local RadioShack store.

Years ago, this would have been occupied by a home theater system, high end stereo, or something that someone would have actually bought, and it would have made the salesperson who helped them with the transaction a good amount on commission.

Now, it’s stupid t-shirts.

Radio Shack is not much longer for this world. They’ve been my go to place when I need a connector or some simple part on short notice, but I don’t think they’re going to be there for me much longer.

They’re the last venture of the Tandy Corporation, which renamed itself to Radio Shack. Tandy Corporation has engaged in many potentially successful ventures over the years, yet methodically run every single one of them into the ground in flames. Some that come to mind, of course, were Incredible Universe, the Tandy Computer brand, TechAmerica, and Computer City.

I used to love Radio Shack in the late 80s through mid to late 90s. They used to have a lot of components and supplies for my tinkering, and it was with the assistance of a Technician class study guide that I purchased at a Radio Shack in 1999 that I got my ham radio license. Back then they still even carried some ham radio equipment in their stores. I remember they still had the HTX-202/404 brick handhelds in their stores, and a 2 meter mobile radio, along with some Vectronics stuff (was this before or after they were part of MFJ Enterprises?). TechAmerica, a mail order only venture (as far as I know) had even more ham gear available when they were around.

What they didn’t have in their stores, they had available in a 200+ page catalog, available for shipment straight to you or to your local store.

In the late 1990s they started to lose focus on what their core business should be. They began to heavily push cell phones, then gradually cut more and more into their retail planograms* to devote more space to cell phones. Eventually, half the store was occupied by cell phones and accessories. Components were pushed back into organizer drawers in one back aisle. They stopped carrying home theater and stereo gear entirely as of about 2010, instead just focusing on low ticket items and cell phones. The commission based sales model would have seriously stopped working for their employees at this point in time, as there’s no longer such a thing as making a $50 commission on the sale of a $500 TV, for instance…

Now, today, I walked into one of their stores and this was in the middle. The cell phone display was pushed against a wall – there’s a good chance they haven’t sold a phone in quite a while, especially since their prices (up front or hidden!) are not competitive with other retail outlets or buying directly from the carriers.

At some point they did make an effort to reconnect with the electronic hobbyist and education markets, but it was all too little, too late. A line of kits they worked on in conjunction with Make Magazine got liquidated en masse at clearance prices…. then promptly reordered. They also carry a number of Seeed Studio kits and boards, but haven’t made any effort to promote this; they are merely just… there.

Despite the large uptick in interest in ham radio, they have not re-entered this market. They don’t even sell TV antennas for those who want to hook up their television sets for over the air programming.

This of course leaves a space for other businesses to fill. Systemax/TigerDirect is now starting to carry electronic kits in their stores. Who knows, maybe you’ll be able to get an oscilloscope there too, just like you can at a Fry’s. Alfa Electronics has been doing great business at their two store locations, and one of my fellow broadcast nerds has started doing some electronic parts sales from his business, Smiling Dog Systems.

It’s just a shame about Radio Shack. The mighty have truly fallen.

The Night of the Smoking Dummy Load.

A couple of months ago, I had a silly adventure. I was at the Homestead tower, just a couple blocks down the street from a Miami-Dade Fire Rescue station that was, at that time, on “brownout” due to Miami-Dade County budget issues. If you want to learn more about how Miami-Dade’s budget and politics work, I recommend you go check out Eye On Miami — I distance myself from politics to make life more pleasant.

The first thing I’m greeted by is a blaring fire alarm in the hallway of the transmitter building and a really foul electrical fire smell, but no particularly visible smoke. I figured either it wasn’t a particularly big one or it had already gone out and the smoke had been evacuated by an exhaust fan. Either way, I proceeded carefully inside and found the alarm belonged to one room on the first floor with the transmitters for Minnesota Public Radio’s classical station. I called their central control as indicated on the door while using an Xcelite “greenie” as a Sonic Screwdriver to gain access.

Harris HT 25 FM - Well it WAS black once.
Harris HT 25 FM – Well it WAS black once.

Inside I found everything coated in some kind of white sticky filth. The air filter on the Harris HT 25 FM transmitter’s power supply was totally caked in it and I’d first assumed this may have been the source, as the power supply was subsequently running too hot to touch. Keep in mind this is a power supply unit the size of a Volkswagen Type 1 “bug”.

At this point he had an engineer on the way to look at it but our conversation turned to what on earth had Let The Smoke Out. See, there’s a theory with electronics, they all work because they have this Magic Smoke sealed inside at the factory.

OLYMPUS DIGITAL CAMERA

Once you let the smoke out, the device never functions again, and it is impossible to force it back in there. Now I wish I’d scraped some of that white gookus off, maybe someday science can figure out how to coalesce it back into injectable Magic Smoke essence. Aaaanyway…..

The person at MPR indicated that he’d had contractor after contractor working on the site, whose maintenance is principally contracted out to Clear Channel Miami. His only indication that there might have been any trouble was that he tried to run a backup transmitter at the site and “it just wasn’t coming up right”. I proceeded to clean their filters while I waited for someone to arrive. OLYMPUS DIGITAL CAMERA

Shortly afterwards I found some very melty things in the vicinity of the dummy load. The site has two transmitters, one antenna, and one dummy load. A coax switch in a DPDT (double pole / double throw) configuration routes the output of both transmitters so that if one is set to antenna, the other is set to dummy load. This way one of them can be run for testing/maintenance while the other is on air, seamlessly. Smokelessly, even, if everything works right…. which it didn’t really.

OLYMPUS DIGITAL CAMERAThe object seen here is the top of the dummy load. Down inside the gray box, there is a star shaped holder clamped to the tops of six noninductive “Globar” type resistors that go down a chimney with a blower at the bottom. RF is applied to the top and grounded at the bottom, and they’re paralleled to form a load that presents 50 ohms impedance at  up to 25,000 watts…. IF THE AIR IS FLOWING. Unfortunately, there was a little oopsie. Note the heat darkening to the metal grille, the white gook splattered on the two pieces of spare feedline to the left…

OLYMPUS DIGITAL CAMERA…And this Krispy Kable…

The air coming out of the load by convection was probably over 500 degrees F. It seems like the resistors got just hot enough to smoke off the coating on the outside but not actually burn out or crack – the load actually tested 50 ohms at DC after the incident.

In the above picture you can see a Bird wattmeter line section. The “slug” which contains the coupling circuitry to pass a reading down the cable as a DC current is not in it. Here is what happened to the slugs from the heat.OLYMPUS DIGITAL CAMERA I call these flame broiled Birds.

The plastic top on one actually became convex and pushed the label off; on the other, the plastic bottom that protects the sampling element warped and tried to fall down the line section when I removed the slug. It’s actually fascinating to see how these work inside, they’re sort of a non-contact coupling with an L/C circuit and a diode. One of these days I’ll have to learn the magical theory as to how these directional couplers work. (Yes, they’re directional – they measure the power flowing in the direction the arrow is pointed, and you can turn them around to switch between measuring forward and reflected power!)

The backup transmitter was a Rockwell-Collins that looked distinctly older than I am. The other guy who showed up on site (whose name I have sadly forgotten) went to turn it on. He pressed filament on… and the dummy load’s blower began running with no problem. Mystery upon mystery, what happened? OLYMPUS DIGITAL CAMERAAt this point we waited for a “ready” indication telling us it was time to turn on the high plate voltage to make it start.

 

The old beast had none.

 

I was actually wondering if it’d light the Plate Off button or something as a ready indication, but it didn’t do that either. I started messing with the multimeter function on the front panel and observed that the meter didn’t work right, and the exciter’s power seemed to have flicked on and off a time or two. OLYMPUS DIGITAL CAMERA

With us both standing in front of the transmitter, he reached for the PLATE ON button.

Old tube broadcast transmitters like this usually run 4000-9000 volts DC on the plate at several amps. When voltage like that finds an unwarranted path, the whole unit tends to respond with an unwelcome BANG. Knowing this, I just about dashed from the room before he could touch the button.

It made two wimpy clacks, but nothing happened. The plate voltage kind of wobbled around but the wattage never went anywhere. The multimeter (when I could get it to work) indicated that the bias voltages were there, but it looked like one supply voltage was missing in action.

He asked me if I had any ideas. I looked at his feet and saw that he was wearing sandals. I was wearing steel toe boots. I said, “Hold on, I’ve got this” and kicked the unit in the front panel. The sound from the transmitter gained a bassier thrumming note, and a glance at the 1897867_10202606324673089_224100874_nmeters showed 25,000 watts output.

To repair something like this, you must truly understand it.

Last I heard they were going to go back in there and reverse-engineer the mess that was made of the control wiring to allow this transmitter to run without the load blower running and its airflow vane switch moving. Alas, the only way I will ever know for sure is the smoke test: Did the building fill with smoke again?

I’m also hoping that Harris HT 25 FM gets a very good internal cleaning at some point. They are known for making some spectacular bangs when they get unhappy.

Tascam CD-500B Button Repair

The Tascam CD-500B is one of a sadly quickly dying breed — a professional grade CD player, with balanced audio output (and AES/EBU digital) as well as RS-232 and contact closure remote control. Unfortunately, it features some very non-professional grade buttons on the front panel. I don’t even understand what on earth they were thinking.

Symptom: Buttons “fall” into front panel. Operation of button is impossible.

Broken off button
Button with broken hinge. Note that the switch is off center and sort of BESIDE the button, not directly under it as it is on Denon players

Problem: Thin plastic hinge section of button has broken.

Solution: Wedge button in place from below so it’s trapped between the front panel, the wedge, and the switch on the circuit board.

Disassembly of the player: This player is truly and sadly built like total BPC (Black Plastic Crap). You have to remove the rack ears, top cover, and the entire front panel. Carefully release the wires going to the front panel and unscrew the one visible grounding jumper. Unplug the two multi pin connectors (they cannot be mixed up – different number of pins). Remove all the silver screws around the front of the player and release the tabs on the right and left sides, then drop the front forward. Remove two screws holding in the LCD, then you can unscrew and remove either button board as needed.

Wedge the broken button(s) from below, then set them into the front panel with it tilted downwards and reassemble.

It is worth noting this player uses what appears to be a standard slotload SATA cd-rom drive as its transport! I have not tried substituting drives yet to see what happens. The buttons break before the transport 🙂

When you and your Arduino do not give a fuck

I can say fuck on the Internet, right?

the wiring is


// fucks.ino: Arduino sketch for automatically running out of fucks to give. Should work on any board, wired to an HD44780 based display or compatible. Does it look like I give a fuck?
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
// rs, enable, d4, d5, d6, d7
// on the lcd end these match to:
// 4, 6, 11, 12, 13, 14
// don't forget the 10k pot between gnd/5v with the wiper on lcd pin 3, ground pin 1, and +5 on pin 2,
// or a completely negative number of fucks will be given. this is undesirable but hilarious.
int fucks;
void setup()
{
fucks=100; // or whatever. watch me give a fuck.
lcd.begin(20,2);
lcd.setCursor(0,0);
lcd.print("Fucks To Give:");
lcd.setCursor(0,1);
lcd.print(fucks);

}

void loop() {
if (fucks>=1) {
lcd.setCursor(0,1);
lcd.print(fucks);
delay(250);
fucks--;
}
if (fucks=0) {
lcd.setCursor(0,0);
lcd.print(" Out Of Fucks ");
lcd.setCursor(0,1);
lcd.print("To Give! Fuck Off.");
delay(30000); // or just go fuck yourself
}
}

I could put up an example picture and video but I am out of fucks to give