1.5 VDC Pseudocell



There's a few problems with the suggested off-the-shelf solution. [1]
The most project fun happened last, after piglet (and another at eevblog) suggested 120R for R1 and 24R for R2. (piglet, with my last sentence, it suddenly became obvious to me why you use R to denote ohms. LOL.) Although 120R and 24R certainly work, you may still ask, "Are they optimal?" ROTFL. Let's have some fun and see! First, you set up a system of simultaneous linear equations (details shown at my updated link: https://crcomp.net/pseudocell/index.php ):
R1 R2
1 -5 0 1 1 150
Then you "plug and chug" the system through octave:
octave:1> A = [ 1 -5;

A 1 -5 1 1
octave:2> b = [ 0;

b 0 150
octave:3> r = A\b r 125 25
Close enough for government work, no? Now, was that fun or what?
Note.
[1] First, there's no nearby electrical outlet to plug it into. Second, it requires a larger, even more unsightly, hole in the wall, to accommodate either a wall wart or pseudocell. The attic's unheated and must be sealed afterward, so the project then creeps into spackle and paint matching.
Danke,
--
Don, KB7RPU, https://www.qsl.net/kb7rpu
There was a young lady named Bright Whose speed was far faster than light;
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In a pinch, you could snip the wire and splice it after you put it through the hole.
--
RoRo

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A larger hole must be drilled in order to push the off-the-shelf solution's flexible cable through it. Stiff wire was pushed through, instead of pulled through with a snake, to keep the hole as small as possible. The solution's cable length is also about 94 feet too short. Perhaps you can spice it to the stiff wire. But it's difficult for me to fully apprise the situation from an image. And unpleasant surprises, after a sometimes long wait for arrival, are anthematic to me. It's also difficult for me to pay $28.99 for parts freely available in my bone pile.
Danke,
--
Don, KB7RPU, https://www.qsl.net/kb7rpu
There was a young lady named Bright Whose speed was far faster than light;
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