Re: Disgraceful!

On Wed, 29 Jan 2025 18:20:50 +0000, Cursitor Doom <cd@notformail.com>
wrote:

On Mon, 27 Jan 2025 13:25:25 -0800, john larkin <jl@glen--canyon.com>
wrote:
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On Sun, 26 Jan 2025 18:29:58 +0000, Cursitor Doom <cd@notformail.com>
wrote:
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On Sun, 26 Jan 2025 09:45:45 -0800, john larkin <JL@gct.com> wrote:
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On Sun, 26 Jan 2025 11:07:14 -0600, John S <Sophi.2@invalid.org>
wrote:
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On 1/26/2025 5:29 AM, Cursitor Doom wrote:

Gentlemen,
 
I never ceases to amaze me that for all I've learned about the theory
side of electronics over the years, my construction skills have not
improved one iota since I was about 10 years old. Case in point:
 
https://disk.yandex.com/i/zGA2slnrNWqGjQ
 
I cobbled this board up to automatically turn on the water supply when
the soil moisture fell below a certain amount. I've got 240V/10A wires
juxtaposed next to low voltage signal interconnects and components
with the insulation smeared through by careless use of a soldering
iron all secured with blobs of hot melt glue and many of the component
lead ends close to shorting out. It's obvious I've paid scant regard
to layout considerations as you can tell. I'm posting this so John
Larkin can see for himself that having the ability to visualize 3-D
apples with insects etc is of no help whatsoever in laying out boards.
Now you might say, "Well, it's only a prototype, CD; it's not as if
you were going to actually use this thing as it stands" to which I'd
have to confess that was indeed my intention! Appalling, isn't it?

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No. The uglier it is, the better it works.

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I disagree. Pretty protos and pcb's and schematics work better, for
some very good reasons.
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https://www.dropbox.com/scl/fi/t7vpf7auh650b2qjfgnk8/D200_BB_4.JPG?rlkey=92oe1louvcpeh91ept0n1w616&raw=1
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https://www.dropbox.com/scl/fi/g27cv9ifg6gwkxphjz4ox/LDP2.JPG?rlkey=0z4y8cge3fg0xwft3hcz329x2&raw=1
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https://www.dropbox.com/scl/fi/ydvcds95zvzjq56bzeimr/Z412_Proto.JPG?rlkey=hyejukxbbnk3573engf0if4zt&raw=1
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Your Dremmeling has improved no end.

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Carbide dental burrs, Mantis, lots of practice.

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There's a 'pen' type extension tool you can get which improves control
no end. Uses a flexible cable with a steel wire inside to convey the
drive from the dremmel. So it's like holding a Sharpie rather than a
bulky lump with a motor in it.
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That board referenced by your middle link above: what frequency is it
intended for?

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That was hundred-amp microsecond stuff. I did that mostly to test some
parts to destruction.

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Using those slender wires and SMB connectors? I know you can get away
with thin stuff for short durations of high current over short
distances, but how did you know your arrangement was good for that
much current?

The wires are gate drive and current monitor.

The circuit should be obvious. Two black things are TVS diodes.