Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
This little critter was chugging across the Dutchess Rail Trail near the ponds north of Page Industrial Park, so I stopped to lend a hand:
Tiny Turtle Dorsal – Rail Trail – 2018-05-23
The plastron looked like a brightly colored jewel:
Tiny Turtle Ventral – Rail Trail – 2018-05-23
Perhaps plastrons start out with all the pigment they’ll ever have, then fade from bright orange to yellow-brown as they spread out.
If you’re not paying attention, you’d think “pebble” or “dog turd”. Neither of which you should ride over, of course, but … teleporting a tiny turtle to the drainage ditch on the far side seemed to increase the world’s net happiness.
The pix are tight crops from the AS30V’s 170° FOV images, which means they’re way grittier than you’d expect from a “full HD” image.
When they happened, I knew where to look, because the Kevlar-belted Primo Comet had two conspicuous bulges surrounding debris jammed between the tread and the carcass along the sidewall: the gashes were wide open!
Much to my astonishment, the tire hadn’t gone instantly flat.
Some screwdriver probing in the leftmost gash produced this nasty glass chip:
Primo Comet gash – chip side view
AFAICT, the smooth side slid over the internal Kevlar belt as the edge sliced between the rubber tread and the carcass. I think the top entered first, with the somewhat crushed end hitting the pavement on each revolution:
Primo Comet gash – chip edge view
The other gash emitted a somewhat smaller chip.
I rode over something crunchy, most likely the remains of a beer bottle, in a shaded section along Rt 376, and we stopped a few driveways later to diagnose a once-per-revolution thump from the front tire. The tube still wasn’t losing pressure, even after extracting the glass, so I continued the mission; it was a fine day for a ride!
I later filled those gashes (plus a few others) with silicone rubber to keep grit out. It’s surely a feel-good gesture, but maybe it’ll help the tire reach the end of its tread life.
You can judge our “riding environment” by the tire’s condition …
As always, we knew this wouldn’t end well for the small lump just in front of the car’s rear wheel (clicky for more, albeit fuzzy, dots):
Turtle 0134 – Vassar Rd – 2018-05-20
So I stopped to lend a hand:
Turtle 1280 – Vassar Rd – 2018-05-20
A fumbling hand, as it turned out, on the turtle’s slippery shell:
Turtle 1364 – Vassar Rd – 2018-05-20
A belly-up turtle in the middle of the road knows the solution to the Halting Problem.
I hoped a secluded spot under a pine tree was closer to its destination:
Turtle 1724 – Vassar Rd – 2018-05-20
However, if the turtle is a female in search of an egg-laying site, then she and all her progeny must cross Vassar Road in the other direction to reach the Mighty Wappinger Creek.
The time-of-day clock in my M20 often resets when I change the battery in the middle of a bike ride.
I turn the camera off, wait for the status light to go out, remove the battery, install the new battery, turn it on, and the time-of-day displayed on the screen has reset to 2016-01-01 00:00:00.
I’m using firmware 1.3.1 (the latest), genuine and fully charged SJCAM batteries, and swap the batteries as fast as I can. Sometimes it works, but maybe half of my bike rides end years before they start! [grin]
It seems my turned-off M20 is extremely sensitive to the power fluctuations occurring during a battery change.
What do you recommend?
Thanks …
Their reply:
The capacity of internal memory battery on main board is very small due to hardware limitation so it can save date and setting for about 10 seconds after pulling out battery.
Would you please check it again ?
I’d call that a design screwup, not a “hardware limitation”. Perhaps I don’t understand how putting a slightly larger capacitor on the PCB, in place of the one that’s already there, would pose a problem.
They also recommend checking with my “re-seller”, but, seeing as how I bought it directly from their nominally official Amazon store, so:
In case they are not able to offer help, SJCAM Technical Department offers a maintenance service. The steps of such service are:
1. You ship the camera directly to our Technical Department address at your own cost (it is located in Shenzhen, China).
2. We check and repair the camera. The repair process usually takes about 3-5 working days.
3. We ship the camera back to you.
Note: The whole process usually takes about 20-30 days, and if your camera doesn’t have damage on the main-board, screen or lens, the maintenance will be free, but we charge 15$ as return shipping cost.
As usual, round trip shipping to Shenzen costs half the price of the M20 camera package, a fact I’m sure they’re well aware of. I did a warranty return to Australia with the Cycliq Fly6, before replacing the battery myself, and (re)learned valuable lessons about warranties and batteries.
I turned SJCam’s offer down, which prompted a curious proposal:
You can send back your camera to SJCAM factory and then we can replace internal memory battery for you.
So the “hardware limitation” has morphed into a (presumably inadequate) internal battery that, when replaced, will resolve the problem. Huh.
Note: you can’t use the M20’s “Car mode” with the timestamp function, because you must remove the battery to let the camera start when the USB power goes on. Unlike basically all other cameras-with-clocks, the M20 wasn’t designed to run its internal clock without a battery.
Improving my battery change speed definitely has the best ROI. Alas, my dexterity has a definite upper limit …
The back tire on my bike was flat when I rolled it out for a ride (the day after replacing the front shifter cable), which ought not be possible with a Michelin Protek Max tube inside. On the other paw, we’ve had zero flats in the not quite two years since installing the things, which says they’re doing very well, and I’ll take a flat in the garage over a flat on the road any day.
With the bike up on the stand, I didn’t spot the expected large glass chip or sharp wire, but I did find three smaller gashes:
Bike tire tread gashes – composite – 2017-05-13
… from which I extracted two small glass shards. Perhaps a wee puncture spent four days parked at the top of the wheel, with the ProTek’s internal goop drained away and unable to plug the slow leak.
Having spun the tire a few times while looking for trouble, I pumped it back up to 80 psi. After delaying the ride for half an hour, the tire pressure remained constant, and we enjoyed a fine ride around the block.
Because I’m writing this in the future, I know it’ll hold pressure just fine, which means I can declare victory and move on.
The tube & tire weigh more than some frames, but they’re worth it!
That’s what all dog owners say when their dog lunges at you:
Dog Lunge – DCRT 2017-05-13
We sounded our usual bike bell dings while approaching and moved as far to the left as we could. The group compressed to the right, which was unusually courteous, we said nothing, and they said nothing while their dog barked and lunged at both of us.
Perhaps we are easily startled, but we do not regard lunging and barking as friendly or sociable gestures. Even as pedestrians, we do not want our crotches explored, our hands licked, or our chests pawed.
AFAICT the only reason Mary didn’t get knocked over and gnawed was a good grip on a thin leash. Maybe the dog would just lick her to death, but it’s still unwanted aggression.
From what I’ve read, dog shoulders operate as front-to-back rotating pivots, rather than all-direction ball joints. Disabling an attacking dog thus requires grabbing its front legs and spreading them as far apart as possible, which is feasible because human arms are much stronger laterally than dog legs. While the process brings one’s head entirely too close to the dog’s jaws, it apparently breaks most of the dog’s ribs, collapses its lungs, and instantly puts it out of action.
I devoutly hope I need never test that maneuver under field conditions, as I can see serious repercussions. If it’s in Mary’s face, however, I will not err on the side of generosity.
Protip: if your dog isn’t well-trained enough to completely ignore strangers, don’t bring it near strangers who may not be dog people.
The genuine Sony NP-BX1 that came with the AS30V camera suffers from voltage depression (green trace) and no longer survives a typical ride:
Sony NP-BX1 – 2018-04-24
The STK C battery (red trace) is also pretty much kaput, so the two of them go into the recycle bag.
The very short blue trace is the Wasabi F battery after a ride, showing about 1 W·h remaining of the initial charge. After a full change, the upper blue trace shows it has a capacity in the same range as the others. Our rides are about an hour long, so the camera draws somewhat less than the 1 A test current, roughly what I’d estimated from other data.
The Smell of Molten Projects in the Morning 