the Hearth @Felthry@awoo.space

what is this exponential graph with a marking halfway between 1 and 10 supposed to be telling me

what is the upper limit of the stable region at high currents

it's very tall

this has been Felthry Has Opinions About Electronic Component Brands Hour, next up: Analog Devices vs Texas Instruments

I'm used to the cheapest capacitors in digikey searches being from like, Panasonic or KEMET or something

so it's really weird when the cheapest three are, in order, Rubycon, United Chemi-Con, and Nichicon

Also apparently Würth Elektronik does capacitors too, we just know them for making high quality inductors

I don't _really_ want to be using a 16VAC input to this, 14VAC is sufficient and it's already gonna be dissipating a lot of power

or some other linear regulator, maybe we can use an LDO and a capacitor that's less than 20mF

okay we're overdesigning this

just gonna, stick a 7815 in there for the 15V thing, use a schottky bridge rectifier and a big cap, and we'll worry about anything on lower voltages when those things actually get designed in

not going to but it should not be this hard to build a power supply using technology that's been around for like six decades

tempted to just say fuck it and stick lead-acid batteries in there all over the place. oof

we don't know enough about magnetics to be comfortable winding our own transformer if it's going to be carrying a nontrivial amount of power

what we know: we need at least 750mA (call it an amp for headroom) at 15V

this is not hard, get a 14V or 16V AC source (transformer) and rectify etc.

but we have reason to believe we may also need a nontrivial amount of current at 5V, and I don't exactly want to be dropping 15V to 5V at like 2A in a linear regulator, so do they make transformers for 14VAC to 5VAC at 10-ish watts, or something like that?

trying to design a power supply when you don't know how much current you're going to need, and when you're concerned about efficiency, and you absolutely have to make it linear (noise would mess up research stuff)... fun times

three is a good number of eyes to have.

Apparently non-lead-free plumbing solder is usually 50/50 tin-lead. I wonder why that is, when it's so far from eutectic? Electrical solder is almost always either 60/40 (a simple ratio close to eutectic) or 63/37 (exactly eutectic).

*loud beeping*

*thinks for a moment, then emits a beep with a 432Hz fundamental and particularly pronounced second, third, fifth, eighth, thirteenth, and twenty-first harmonics, lasting exactly one second*

megamon, gotta get equipped with 'em all