Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
One of the Coopers Hawks that keep the rodents under control around here landed atop a pine tree and spread its wings to dry out:
Coopers Hawk drying in pine tree
Shortly thereafter, the second hawk arrived and the pair shared some Quality Body Maintenance time:
Coopers Hawks in pine tree
The first image comes from the Sony DSC-H5 with the 1.7 tele adapter. The second is from the Canon DX230HS with the digital zoom set to 2x “digital tele adapter mode” and the optical zoom cranked all the way out; they’re both small crops from larger images. Not much to choose between the two, although the Canon wins hands-down for convenience.
While thrashing around with that DVD player, I finally figured out that VLC stores its configuration settings in ~/.config/vlc/vlcrc. I don’t know if it’s supposed to update that file automagically after twiddling the GUI config settings, but it doesn’t; I must manually edit the file to get a sticky change.
Anyhow, the vital setting for that particular drive turns out to be audio synchronization, as set by the audio-desync parameter. The audio must lag the video by 400 ms, thusly:
So I picked up a cheap digital scale at Harbor Freight because it can count parts based on weight. After all the dust settled, it was on sale for about $8, which tells you just about all you need to know, and the “5 Year Warranty” looked generous on the box:
Harbor Freight 1 kg Scale
Alas, the fine print taketh away (clicky for more dots):
Warranty
Ah, well, all this stuff is disposable anyway, right? Nobody’d ever try to fix it…
The instructions for the Count function omit a step. In order to invoke the Count function, do this dance:
Turn it on
Count exactly 10 pieces on the scale, wait for stabilization
Press-and-hold PCS until the display shows 10
Release PCS
Press PCS briefly; the pcs annunciator turns on (they omitted that)
The display will still show 10, which is the number of pieces
Now you can weigh stuff and read off their counts
The scale resolution is 0.1 gram, so SMD resistors just aren’t going to count properly at all. It’s best if you add the entire group at one time, rather than trickle parts into the pan.
Well, it turns out that the DVD drive I stuffed into that case really does require a whole bunch of current. I tried playing a DVD and got erratic results, including weird keyboard (!) failures. Finally, I hitched a bench supply to the coaxial power jack on the case and caught it in the act:
Laptop DVD – current display
That jack normally connects to the power-only USB cable, which implies an upper limit of 100 mA. A bit of poking around inside shows that the coaxial power jack simply parallels the USB jack’s VCC line, so there’s no fancy negotiation or current sharing going on.
When the keyboard went nuts it was sharing an unpowered USB hub with this thing, which means that the overcurrent dragged down the hub’s supply. I was permuting all the choices to see if the failures suggested anything; eventually it did.
A bit of rummaging in the Basement Laboratory Warehouse Wing uncovered a 5.0 V 3.7 A wall wart switching power supply that is grossly in excess of the drive’s 1.5 A rating. Amazingly, it even had the correct coaxial power plug on the end of the cable, which never happens.
Alas, because the external supply back-powers the USB data cable, it lights up the Q150’s power button when the PC is turned off. I think I can insert an isolation diode into the USB power trace to isolate it from the jack, somewhat along the lines of that hack. However, that seems to require removing the USB connector to uncover a very well protected top trace. For now, I’ll just unplug the drive.
That tag should ensure any TSA agent will sideline me for an enhanced inspection sufficient to reset breakfast to last Tuesday. Or I get to ride in the cockpit. Maybe both.
Aitch is one of the very few people in the world who can use a business trip to the Atacama Desert as a cover story for his real activities, about which I know absolutely nothing because I’m Still Alive™. The fact that he returns with a camera full of gorgeous pix merely demonstrates the cover team’s finesse. The NSA schwag came from another trip. So he says, anyway.
Oh, that tag originally hung from the drawstring of a very nice black velveteen pouch containing an NSA-logo sippy cup along with the matching coaster. All made in China, of course: if irony were energy, we could saw off the entire Middle East and be done with it…
Scaling the cubes to about 15 mm on a side puts a 6×6 array neatly on the build plate. Takes nigh onto four hours to print all 36 of them at 30 mm/s print and 100 mm/s move… a bit over 6 minutes each.
The print quality is Good Enough. The bottom surface of the front cubes faces forward and reflects the scale markings:
A pair of fritillary butterflies have been enjoying the butterfly bush at the living room window. The first one has a slightly tattered wing:
Fritillary butterfly – dorsal
The camera can’t do justice to the silver patches on the bottom of the rear wing. They’re not reflective like a sheet of silver, but they shine like metal in the light:
The Smell of Molten Projects in the Morning 