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Charlotte and a shrew
Friday, March 29 2024
location: 940 feet west of Woodworth Lake, Fulton County, NY
Though I'd made a weak attempt not to drink too much booze last night, I woke this morning with a mild hangover, which isn't all that unexpected. I made myself a french press of coffee and fed the dogs when they appeared (Neville had slept with me in the large first floor bedroom but Charlotte had slept in the loft beanbag as usual).
In a continued effort to find the cause of Charlotte's itchy skin, recently Gretchen got a bag of Purina Hydrolyzed ProPlan Veterinary Diet, which is supposedly vegetarian. Our vet suggested this, claiming it was low in the allergens likely to trigger Charlotte's skin problems. It looks weird, with the kibbles having a pale bleached color. That must be the effect of the hydrolyzation. Last night, though, I'd made a problematic discovery: Neville loves the new food but Charlotte can't stand it. So what ends up happening is that Neville eats all his food and then eats Charlotte's, and she's left with nothing to eat. I'd been under strict orders not to let Charlotte eat anything else, but that clearly wasn't going to work. So this morning I made her a peanut butter sandwich with a piece of stale bread.
After drinking my coffee and switching to kratom tea, I resumed work on my remote control system, focusing on the hardware aspect. I'd decided to rework how the system would be organized. Instead of having some janky wires intercept power to be switched by relays at the circuit breaker box, I decided the relays should instead be safely inside junction boxes near the circuits they control. I don't know how to make any of this code-compliant, but doing it this way would at least be safer than having relays attached to live current out in the open air.
I also wanted my NodeMCU to be able to make lower voltage connections of the sort where using a relay would be overkill. For this functionality, I thought I could use some optoisolators (also called optocouplers), devices that contain an internal LED optically-coupled to a photo transistor so that the former can control the latter without any electrical connection between them. (I've only ever used optoisolators to electronically bridge the equal button on a calculator to make it count upward on its own, something that seemed mind-blowing when I did it at the age of thirteen back in 1981.) A good application for optoisolators would be to reset the Moxee cellular hotspot (I currently bridge its on button using a low-current relay) or turn on the Generac generator. So I spent more time than I should have installing and wiring up a 28 pin socket, which is big enough to hold seven optoisolators. I installed connector pins and current-limiting resistors that will allow me to hook things up to it.
Since I don't have anywhere near the amount of on-hand scrap to root around in for odds and ends, I had trouble coming up with reisitors of the correct value. I had a box of ancient unused resistors that had been in some old man's toolbox I'd bought at the the Tibetan Center thrift store, but there was only one resistor of the right value it that and it was a huge one designed to dissipate a lot of current. Fortunately, though, I happened to have a scrap analog board from an old CRT monitor that I'd prudently thought to bring to the cabin, and it had two resistors of a close-enough correct value.
Beyond creating the circuitry to support two optoisolatators, I didn't go any further on that tangent. Instead I shifted my focus to the practical problem of what junction boxes I should use for holding the relays and what wire I should run to supply them the 12v needed to switch them. I had a number of metal boxes, but the problem with them is that drilling a small hole through them for the 12v cable would result in sharp edge that could cut into the cable. So I was thinking maybe it was best to use plastic boxes. Unfortunately, the boxes I had on hand weren't really right. So I loaded up the dogs and drove to the True Value hardware store in downtown Glovesville. Since a conventional hardware store doesn't really cater to the specifics of what I was doing (this is pretty common for my kind of projects), it was best that I be left alone with my thoughts as I selected the things I needed. Fortunately, the staff left me alone to do this.
Back at the cabin, it seemed like the dogs were itching to go for a walk. So I grabbed the big Kobalt electric chainsaw (now with a brand new blade) and headed with them down to the lake, stopping to cut chunks out of a couple trees that had fallen into the trail over the winter. Down at the lake, I saw that it was still about as frozen as it had been when I'd last visited, though it looked like there was more thawing out across the lake near its eastern shore. There also looked to be a fairly large swath that had been liquid at some point earlier in the winter and then flash-frozen, preserving the state of all the ripples. (I'm not saying that's what happened, but that's what it looked like.) From there, I took the dogs north along the lakeshore towards the outflow beaver dams. Along the way, I found a 12-inch-long by four inch log that tapered to a chiseled point on each end. Clearly this was an artifact made by a beaver, and it was so striking that I decided to carry it back to the cabin with me. Soon thereafter I heard a high-pitched chirping coming from a small patch of ground that Charlotte had cleared of snow. When I went over to investigate, I found Charlotte had exposed a tiny shrew who had been going about his business beneath the snow. But she was just curious and didn't mean the shrew any harm. I called her away and the threw some snow on the shrew to help him hide from Neville, who wouldn't've been as kind.
After passing the beaver dams, Charlotte walked across the outflow creek on the little stony causeway, indicating she really wanted to go walking over there. So I ended up taking the dogs for a pretty substantial walk to the northwest all the way to the State Park boundary. Due to the deep shade of the hemlocks, some of the snow along the way was still as much as a foot deep. I was a little worried about Neville, who plods along like an old man. But he managed to keep up pretty well and, when the terrain got too rough (when I was climbing up along the steep, shallow gorge that the outflow creek forms as it approaches state land) Neville found easier terrin to walk in.
Back at the cabin, I stayed up late implementing and testing a relay (technically it's a contactor) inside a double-size PVC junction box with a duplex outlet to control. I'd decided to use four wire telephone cable to carry the 12v to the relay after testing it and finding it easily worked across about 50 feet of such wire. To further improve its reliability, I decided to combine the red and yellow wire and the green and blue wires so as to double their current-carrying capabilities. Once I was happy with all that, I connected it to an existing outlet box near the northeast corner of the cabin's basement, near the two other circuits I want soon to be remote-controlling (the boiler and the hot water heater).
The contactor, with a nearly-installed outlet (to be controlled by the contactor) and the telephone cable carrying the control signal. Click to enlarge.
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