Another picture from the Arlington Marching Band competition at The Dome in Syracuse.
Silhouetted Flags
These are flag twirls against portable mercury-vapor floodlights. The glare off that bare tree make the scene look just about as cold as it really was, even if it wasn’t icy.
The camera picked 1/5 second for this exposure, although the translucent flags don’t show the same strobing as the bright-white rifles. I think the lower floodlight is the same one in the single-rifle picture.
Took these pix while chaperoning the Arlington High School Marching Band trip to The Dome at Syracuse University. They’re warming up, if that’s the proper word for standing around in skintight uniforms on a 45-degree evening at Skytop, in preparation for their show.
Many Strobed Rifle Tosses
The ISO 1000 setting on a Sony DSC-H5 produces absolutely terrible color noise, but sometimes it just doesn’t matter. These were taken under low-pressure sodium-vapor parking lot lights, with some mercury-vapor lighting in the background, so they’re basically monochromatic anyway.
Single Strobed Rifle Toss
The shutter is 1/8 second and the lights flicker at 120 Hz, so the rifles reflect 120/8 = 15 blinks as they spin. The similar included angles show that all the rifles spin at nearly the same rate: the Color Guard does very nicely synchronized tosses. They’re good!
Now, for one of my top-ten favorite pictures…
I moved around to put the mercury-vapor light behind her, which prevented flareout & added a crisp edge. The camera managed to get nearly the right exposure, even under considerable duress. This is a crop from a larger image.
She’s absolutely stationary with only her hands moving, exactly the way it’s supposed to be done.
Despite the slow shutter speeds, they’re both hand-held pictures. You simply don’t get to see my botches…
Oh, and by the way. The “rifles” are wooden dummies, carved out in a general rifle-stock shape, but without any metal parts or even a barrel. Frankly, I think the Color Guard should be trained up in marksmanship and carry actual rifles. Perhaps those would work well?
Linear Technology’s LTSpice generic capacitor model has all the parts you need to synthesize a crystal, which is pointed out in the help file and various spots around the web. What’s missing is the relation between all the parts and the values you have in hand for an arbitrary crystal.
SPICE Capacitor Model
The crystal capacitor model looks like this…
Cpar (usually C0) along the right edge is the inter-electrode capacitance, on the order of a few pF.
Rpar (usually R0) along the left edge is the parasitic resistance across the case, on the order of hundreds of MΩ.
The RCL string in the middle is the “motional” part of the crystal model, generally found with a subscript “m” in the specs.
Crystal Properties
Now, the part I screwed up is that the capacitor’s value (the number appearing on the schematic) is Capacitance (in the angle brackets that royally screw up WordPress HTML), not Cpar. So the crystal capacitor properties panel looks like this…
That models a 10 MHz crystal, taken directly from a sidebar in Refinements in Crystal Ladder Filter Design by the legendary Wes Hayward W7ZOI, in the June 1995 issue of QEX.
Guess what? Plug it into a model of his crystal-measuring circuit and it works exactly like he says it should. No surprise there…
SPICE has a bit of trouble simulating high-Q oscillators; they tend to not start up properly. If nothing seems to be happening, wait for a few tens-to-hundreds of milliseconds before despairing. Try chopping Rser down by a factor of two or four to see if that improves its disposition.
You could try injecting a few (hundred thousand) cycles of a kickstart signal, but that’s fraught with peril: you’re simulating something even further from reality than usual.
Memo to Self: You can rename the cap from C2 (or whatever) to X1 (or whatever) and everything still works fine.
Found this on the long-disused stage of the former Martha Lawrence School, now the St Francis Hospital Daycare Center, hosting the polling place where I was serving as an Election Inspector. It’s a bit hard to read, even in the larger version, but I thought a one-year warranty etched into a brass plate was interesting; it’s screwed right to the side of the dimmer panel.
Lighting Switchboard Warranty Placard
The warranty provisions require that the dimmer panel be properly maintained, regularly used, and kept clean. As you can easily see, it’s been a long while since anyone has put on a stage production.
I think the warranty ran out right around the time I was born, but I could be off by a decade or two either way.
Lighting Switchboard Dust Accumulation
Voting Machine LCD Touchscreen Miscalibration
This is on the “control panel” side of the Sequoia ImageCast Ballot Marking Device voting machines used in Dutchess County. I put my finger in the middle of the CLOSE POLL button and the panel misread a press on the REPORTS button.
That’s one of several misreadings of the day. Earlier, while setting up the machine for the day, it misread horizontally and gave me a STATUS report instead of a ZERO report.
Last year the same sort of thing happened. It’s always explained as “being out of calibration”, which makes me wonder just exactly when the panels are calibrated and what the criteria for success might be.
One of the few good things to come out of having a totally dysfunctional State Legislature is that New York has managed to delay and stall and fumble around until other states demonstrated the utter stupidity of direct-recording, no-paper-trail electronic voting machines. The ImageCast machines are a spectacular boondoggle, but far less catastrophic than what we’ve seen in Florida, Ohio, California, and …
Oh, and after a 16-hour shift as a BMD Election Inspector, exactly zero handicapped voters (actually, any voters) took advantage of the machine to cast their vote. A report from someone who’s in a position to know says that in the last election, the bottom line was $250 per vote on the ImageCast machines. I think that’s probably low.
My tax dollars at work, fer shure!
We stayed at the Syracuse Sheraton while chaperoning a Marching Band trip, which led to meals in the Regents Ballroom, a large space (potentially) divided in three parts by the usual folding partitions. The wall in each section had a bank of RJ-11 and -45 jacks…
Hotel Ballroom Phone and Data Jacks
Obviously, back in the day, a single room with 25 Phone jacks and one (red) Data jack made perfect sense. Or maybe the ballroom has 75 phones lines and three Data connections? Hard to say.
Judging from the overall crud accumulation, the jacks aren’t getting much use. I wonder if it was originally set up so they could run a boiler-room operation out of the hotel ballroom?
Ten Pound Hershey Bar
Several decades ago I got my esteemed wife a ten-pound Hershey bar for Christmas. She said that was a thoughtful gift, exactly what she wanted, and if I ever did that again, she would kill me.
Turns out that I’d gotten such a bar myself, many many years ago…
These days, of course, the biggest Hershey’s Chocolate bar you can get is a measly five pounds.
Guess what? Update Firefox to 3.0.15 in Xubuntu and we’re back to the continuous restart reminder situation I mentioned there.
Same fix applies this time, too.
Aerator filter disassembly
I’m sure they have more different versions of these things than anyone can count, but when I unscrewed the kitchen sink aerator, this is what I found inside.
The yellow plastic filter actually has two parts, held together by a minuscule clickstop on the central post. You can pry the whole thing off the main body with your thumbnail or, as in the photo, just pop the top screen off.
Rinse the grit off the screen, snap it back together, screw everything back onto the spout. Done!
It’s amazing how much grit accumulates downstream of the whole-house water filter. On the other paw, having just replaced the water heater, I’m not that amazed.
Once again, the faucet O-ring seals are leaking. This happens about every two years, perhaps due to mineral buildup in the spout body despite the water softener. Fortunately, it’s a dribble rather than a spurt, so it’s not an emergency.
This is a Home Depot (or was it Lowe’s?) faucet, but they do not stock repair parts. Go to FaucetDirect.com, order these parts:
Popping off the button
Of course, order two or three of each, because FD has punitive shipping rates. Ten bucks for a few envelopes of O-rings? Sheesh… but the last time I tried to get ‘em locally, they were No Stock. If I’ve got to wait around, I’ll have ‘em delivered to my door.
The first puzzle is how to get the faucet apart. After making a mess of it the first time, it turns out you poke a small flat screwdriver inside the handle and pop the red-blue button out. It’s held on by two small tabs, one on each side, and if you can just push one then it’ll ease right out. It is not a screw head, despite the recessed slot down the middle.
Poke a 3/32″ hex key in the hole, back out the setscrew a few more turns than you think it takes, pull the handle off.
The plastic cap retainer has two arms holding the escutcheon ring in place. Push inward, remove the escutcheon. The retainer is probably hopelessly jammed into the top of the faucet spout, so if it doesn’t come out, that’s OK.
Loosen the three screws holding down the valve cartridge, pull it straight up and out. You did turn the water off first, right? Remove the plastic spacer plate and three O-rings below it if you can; the plate may not fit through the retainer.
Faucet column
Now, get comfortable on the sink. Pull-and-twist the spout straight up with far more force than you think necessary. It will suddenly fly off and bloosh the water that’s been standing in the faucet column all over the place.
You’re left with a rather grody column and the two offending O-rings. Note the orientation of the silver flange ring at the bottom and the lower white plastic bearing ring. There may be three O-rings stuck to the top surface; they belong inside the spacer plate.
Remove all that hardware and scrub the grodosity off the column.
Hint: if you’re weak of stomach, never look inside your drinking water fixtures, because you’ll never drink tap water again.
I generally soak the spout in vinegar for a bit, scrub it out with a toothbrush, ease the remaining deposits off with a small screwdriver, then scrub the whole thing down with a ScotchBrite pad.
I apply a very very very thin layer of silicone lubricant to the bearing surfaces inside the column, which makes the next step possible.
Put the flange ring, the new O-rings, and plastic bearing rings in place, then slide the spout assembly straight down over the column until it bottoms out with a thump.
Install the new spacer plate & its O-rings, then reassemble all the other doodads in reverse order, turn on the water, and you’re done.
Then forget all the crud you saw in there that you couldn’t clean out.
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