#garfield Logs

Nov 27 2021

05:42 AM rue_mohr: polprog, https://www.4qdtec.com/mvibs.html come play...
05:50 AM Tom_L: morning
05:50 AM rue_mohr: heh
12:13 PM rue_mohr: morning
12:13 PM rue_mohr: this time for real
12:44 PM Tom_L: hah
12:44 PM Tom_L: but it's afternoon
12:58 PM rue_mohr: I'v had my shower!
12:58 PM rue_mohr: next: breakfast
12:58 PM rue_mohr: if I want to eat...
12:59 PM Tom_L: have supper now so you can get it out of the way
01:49 PM rue_mohr: hmm, how to read +-100VDC with an avr...
01:52 PM rue_mohr: ah, op-amp with a 1M input resistor looks ok
01:52 PM rue_mohr: tho resolution is 0.2V
01:54 PM rue_mohr: if I use a current source and a timer I get lots more resolution
01:55 PM rue_mohr: at 8Mhz i'd get 40000 counts
02:13 PM rue_mohr: hmm, worst case
02:14 PM rue_mohr: the freq goes down
02:14 PM rue_mohr: I need to focus and finish my power supply for the driveway
02:14 PM rue_mohr: flyback, 20W
03:56 PM aandrew: yeah just use high value resistor and let the built in ESD diodes shunt the tiny current
03:57 PM aandrew: and if you want actual voltage, just a sufficiently large divider :-)
04:16 PM rue_shop3: so, cleaning up breadboards
04:17 PM rue_shop3: part of what I'm left with is
04:17 PM rue_shop3: a floppy drive pfm direct audio storage project
04:17 PM rue_shop3: 3 servos
04:17 PM rue_shop3: 7 random microcontroller boards
04:18 PM rue_shop3: a rom that runs a 5x7 led array and displays the ascii character fed to it
04:18 PM rue_shop3: and a small UV lightsource (boost supply)
05:43 PM aandrew: so I love these spool holders: https://www.thingiverse.com/thing:3407527 but they have a problem where the spool tends to wander off the bearings
05:44 PM aandrew: so I made this: http://mixdown.ca/dump/spoolholder.stl which you pop the bearings in to and then push the bearings on to the mounts as normal
05:44 PM aandrew: hopefully it will work better
07:32 PM rue_mohr: yea
09:05 PM rue_shop2: one of the ups' in the shop is venting sulphor fumes
09:05 PM rue_shop2: bbl
09:57 PM rue_shop2: test 1 2, can you hear what I'm saying?
10:16 PM aandrew: indeed I can
10:56 PM rue_mohr: so the step-down circuit didn't work
10:56 PM rue_mohr: ok
10:56 PM rue_mohr: I have a step up/down that I want to make