phooky @phooky@octodon.social
Hardware, hackerspaces, retrocomputing, sketching and occasional weird tasks. Personal toots @phooky
https://octodon.social/media/AlCwOnneuKNG4JboRqU wirewrap intensifies
Got around to fixing the distortion in the display. My hacky OR gate was at fault; the pulldown after the diodes was ~500Kohms, but there was a ton of capacitance in the input being driven (74LS244 @ 5V), so minor power fluctuations were screwing up the sync. Went to a 680ohm pulldown and now it's solid.
How shitty are my microscope's optics? This shitty: https://octodon.social/media/taRkka9HoKcaHrIO8Oo https://octodon.social/media/e9VS_zHUtVglwrAfafc https://octodon.social/media/wmTAOz1b4o_6813LeC4
(yes, i've got replacements on the way)
Hey, remember how the other day I was like "Should I extract the font from this chip by decapping it and looking at the ROM under a microscope?" and everyone was like ha ha you're so funny no one would ever do that and so long story short WHO'S LAUGHING NOW
https://octodon.social/media/najfKdb8cyqiDrP1oSk https://octodon.social/media/XvSUXiducUcrXOSAqPA https://octodon.social/media/tcVNRIoTgHz5DmArJz0
does anyone have a hint as to what could be causing this kind of distortion? https://octodon.social/media/B3RaQ2Mu6NMKAwkn1aE https://octodon.social/media/BZdWbXfb8rJHx7sSrEk https://octodon.social/media/MKgsXV2e7pSusgFkZXc
Today in unexpectedly successful chemical free chip decapping
https://octodon.social/media/nF6IetaAm5QXNzlJx7Y https://octodon.social/media/FJ7VTVrvzKTtxwI7u6w https://octodon.social/media/7YEIN8ubVEqXRzgG5Bk
looking good! OSH Park just shipped my PCBs, so this is starting to look like it's going to happen for real.
yesssssssss
Couldn't remember what chip I was using as 3.3V->5V level shifter. Then found the part number in a single frame from the timelapse where I was holding the rail in front of the camera. Nice. https://octodon.social/media/qoEI8chzt0g7pySaUSk
It works. Don't know how or why it works, but somehow it works. Now to track down the rogue interrupt on the teensy...
Also, still trying to identify or characterize this transistor. Circa 1980; device designed in France but maybe manufactured elsewhere; operating in the 60V range. Maybe (but not likely) related to http://pdf1.alldatasheet.com/datasheet-pdf/view/30419/TOSHIBA/2SC5468.html
Any thoughts?
My first schematic in #kicad (video output stage for my weirdo Minitels). I still feel like Eagle is more intuitive; every time I do anything in eeschema I feel like I'm supposed to know where everything's going to end up at the outset, or should sketch it all out on paper before laying it out.
https://octodon.social/media/U_CB1p6cQijDBL-rpkE
