#garfield Logs

Jun 13 2021

#garfield Calendar

11:25 AM rue_bed2: seems to be an inside stuff day
11:39 AM Tom_L: not here, been out and mowed
11:55 AM rue_mohr: !!!
11:55 AM rue_mohr: I either have a large pile of plastic in a printer or the box is printed!
11:55 AM Tom_L: might be worth a look ehh?
11:56 AM rue_mohr: looks like a box!
11:56 AM rue_mohr: I'm supposed to cast it with the lid on, right?
11:56 AM rue_mohr: :)
11:57 AM rue_mohr: (didn't print the lid yet)
11:57 AM Tom_L: how'd the lettering come out?
11:58 AM rue_mohr: fine
11:58 AM Tom_L: err maybe i should ask that after the casting step
12:00 PM rue_mohr: you saw the lines in the other part from the printing grain eh?
12:00 PM Tom_L: yes
12:00 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1190994.jpg
12:01 PM Tom_L: nice
12:01 PM Tom_L: you get some good prints
12:01 PM Tom_L: what infill?
12:01 PM rue_mohr: this one is 15%
12:01 PM rue_mohr: it doesn't need to be strong
12:02 PM Tom_L: put your holding screws by the boss's or you might poke thru
12:02 PM rue_mohr: minimal plastic
12:02 PM rue_mohr: I was annoyed I couldn't get the other one out without screws
12:02 PM Tom_L: yeah i figured it would be minimal
12:50 PM rue_mohr: the sun is kinda out
12:50 PM rue_mohr: huh
12:52 PM * Tom_L is betting he can keep rue_mohr busy in the casting business for some time
01:08 PM rue_mohr: I dont know if its reliably dry enough today for casting
01:08 PM rue_mohr: but I'd like to get the jukebox up
01:09 PM Tom_L: weather makes a big difference?
01:09 PM rue_mohr: rain is BAD
01:09 PM rue_mohr: melts the casting sand and solidifies the metal
01:09 PM Tom_L: well yeah, especially if you're doing it ouside :)
01:10 PM rue_mohr: and I need to write invoice 43!
01:12 PM rue_mohr: 34
01:42 PM rue_mohr: Tom_L, so, what you gonna design next?
01:52 PM rue_shop2: I'm going to see if I can get this esp32 bitbanged colour composite video working
02:09 PM Tom_L: you shouldn't put off collecting money that long
02:09 PM Tom_L: i can design whatever you can come up with :)
02:16 PM rue_mohr: oh no, I'm not your only source of insiration!
02:18 PM Tom_L: i'm not building anything at the momemt
02:18 PM Tom_L: need to keep up on the cad though obviously
02:19 PM Tom_L: when i was taking the class i could have done both of those in probably an hour or less
02:19 PM rue_mohr: :)
02:21 PM Tom_L: and have time left to help the guy next to me
02:21 PM Tom_L: (he never did get it)
02:29 PM Tom_L: i did that mostly just for fun
02:29 PM Tom_L: both kids took more classes than me on it
02:45 PM Tom_L: surely you need more things designed on your big mill :)
03:24 PM rue_shop5: not sure
03:24 PM rue_shop5: I got the clamps for the router, and need to build up the Z axis
04:06 PM polprog: evening
04:06 PM polprog: I fixed the lamp today, i can work at night now
04:06 PM rue_mohr: haha
04:07 PM Tom_L: yeah who needs sleep!
04:08 PM rue_mohr: I'm pretty impressed with the bit-banged video from the esp32
04:08 PM rue_mohr: I think they used the DAC tho
04:09 PM rue_mohr: but getting 3.5MHz from the dac is pretty good
04:09 PM polprog: yep
04:09 PM rue_mohr: dma or not
04:09 PM rue_mohr: the camera did it a lot of justice, its actually kinda dim
04:09 PM polprog: ive been playing with the pierce oscillator yesterday
04:10 PM rue_mohr: ah!
04:10 PM rue_mohr: any success?
04:10 PM polprog: i have to re-try it with the new NPNs, i cant get the JFET to go faster than 40MHz
04:10 PM rue_mohr: hmm
04:10 PM polprog: they are 400MHz bandwidth
04:10 PM polprog: I dont know why. But the crystals are running lower than rated
04:10 PM polprog: 100MHz makes 20, some other makes 40MHz
04:10 PM polprog: i cant get it to drive a 50 ohm load
04:11 PM polprog: tried making a matching transformer but no luck there, probbaly not enough windings, has not enough impedance at that frequency
04:11 PM polprog: and loads the output too much
04:15 PM rue_shop5: crystals have different harmonics
04:15 PM rue_shop5: depending on how you drive them you get different frequencues
04:15 PM polprog: it's a standard pierce oscillator
04:15 PM rue_shop5: I have another 100 pin cpld to play with
04:16 PM rue_shop5: heh, I can never remember which oscillator is which
04:16 PM rue_mohr: is heartley with a center tapped coil and collpits with a center tapped capacitor?
04:17 PM polprog: i dont remember
04:17 PM polprog: but pierce is the one with crystal
04:18 PM polprog: with jfet the biasing is basically a large R to source
04:20 PM rue_mohr: hahah libera is less stable than freenode
04:21 PM polprog: timeouted?
04:21 PM polprog: heh
04:21 PM polprog: i wonder how their server net looks, geographic-wise
04:21 PM rue_mohr: I think that esp32 video was the last thing for my weekend bucket list
04:22 PM polprog: neat
04:22 PM polprog: I think i will get some more of these jfets, got 2 left only
04:22 PM polprog: got 5 then
04:22 PM polprog: 2 blew up, 1 in circuit, 2 in stock
04:22 PM rue_mohr: hmm
04:22 PM polprog: and ill try to resolder the circuit to be more in the air
04:22 PM rue_mohr: so
04:22 PM polprog: maybe my chokes are crap
04:23 PM rue_mohr: what do you think of finding a work-from-home engineering job?
04:23 PM polprog: the 22uH / 2.2mH ones were pulled from a video
04:23 PM polprog: id say if it's a good job take it
04:23 PM rue_mohr: what about 130 jobs over a year for $1M?
04:24 PM rue_mohr: each 4 weeks
04:24 PM rue_mohr: 9 at a time
04:24 PM polprog: what do you mean
04:24 PM polprog: so maybe the chokes are not choking at that frequency
04:24 PM rue_mohr: well, the question is, would you do it for $1M
04:25 PM polprog: the behavior changed completely when i added a 100R in series
04:25 PM polprog: depends what kinda jobs
04:25 PM rue_mohr: even 22uH chokes a freq pretty fast, you had a series resistor, right?
04:25 PM polprog: yeah..
04:25 PM rue_mohr: how about jobs where nobody even cares if you do a good job?
04:26 PM polprog: ill just rebuild it and take better notes
04:26 PM polprog: you mean govt jobs :P?
04:26 PM polprog: nah, id stay away
04:26 PM rue_mohr: hmm
04:26 PM polprog: id go crazy in a job like that, or go fuck-all
04:27 PM rue_mohr: $1M/year for a year?
04:27 PM polprog: i dont know how much is $1M a year where you live
04:27 PM rue_mohr: is $1M USD/year much for you over there?
04:28 PM polprog: quite a lot
04:28 PM rue_mohr: it would build me the new house and shop I need
04:29 PM polprog: hmm
04:31 PM rue_mohr: so
04:31 PM rue_mohr: the thing I'm uncomfortable with, regarding the cplds
04:31 PM Tom_L: some ppl do that under govt contract in war zones
04:31 PM rue_mohr: is that its got firmware on it
04:31 PM Tom_L: pay is good
04:32 PM Tom_L: slight risk
04:32 PM rue_mohr: its not just a chip that does a thing
04:32 PM rue_mohr: Tom_L, work from home is all over the place now
04:32 PM rue_mohr: covid made things explode
04:33 PM Tom_L: yeah
04:34 PM Tom_L: economy is crap too
04:34 PM Tom_L: i don't blame that all on covid though
04:35 PM rue_mohr: covid did a work-from-home thing tho
04:35 PM rue_mohr: hmm
04:35 PM Tom_L: funny how it all happened during an election year
04:36 PM rue_mohr: can I implement a 4 channel, parallel interfaced, 8 bit pwm system on a 9572?
04:36 PM rue_mohr: I think I can
04:36 PM rue_mohr: about 40 latches
04:36 PM Tom_L: may take all 72 cells
04:36 PM rue_mohr: but comparing numbers hits it pretty hard, so manybe not
04:37 PM rue_mohr: I always wanted pwm speed control on the lawn mowing robot
04:38 PM rue_mohr: I was playing with serial interface to the cpld, but the extra shift registers burn things up really fast
04:38 PM rue_mohr: like, a working register for shifting the serial and an output latch for the final value
04:39 PM rue_mohr: its only 16 io
04:39 PM Tom_L: mine is a 108 i think
04:39 PM rue_mohr: I'm finding 9572s everywhere
04:39 PM rue_mohr: seems to be defacto-standard for glue-logic
04:39 PM Tom_L: for small things yes
04:40 PM Tom_L: it was probably their small one of that series
04:50 PM rue_mohr: yea
04:50 PM polprog: i just noticed my pierce oscillator does not have a C between the jfet base and ground
04:50 PM rue_mohr: I'm kinda sad I dont have the stuff to reverse engineer whats on them
04:50 PM polprog: jfet gate
04:50 PM rue_mohr: see what people are doing
04:51 PM polprog: i forgot about it because i would put a too big cap and blow the jfet, but i could put a couple pf there, maybe even a varicap and see if that works
04:54 PM rue_mohr: your definitly need a series resistor with the choke inductors tho
05:08 PM rue_mohr: yea, sorry
05:08 PM rue_mohr: the capacitance between all the windings
05:08 PM polprog: something I picked up
05:08 PM rue_mohr: yep
05:08 PM polprog: i had that board with sooo many tht lump style inductors
05:08 PM polprog: got at least 10 off of it
05:08 PM rue_mohr: :)
05:09 PM rue_mohr: the blue lumps with the dots?
05:09 PM polprog: yup
05:09 PM rue_mohr: hah, I think those are funny
05:09 PM polprog: I wonder if the inductors used on various digital boards are any good for RF
05:09 PM polprog: i hae a couple of these in the immediate scrap cache
05:09 PM rue_mohr: 100Mhz is pretty high
05:09 PM rue_mohr: you doing it on a baordboard?
05:09 PM polprog: i wanna to do 400MHz :D
05:09 PM polprog: ofc not, manhattan style
05:09 PM rue_mohr: ok
05:09 PM rue_mohr: I was gonna say
05:10 PM rue_mohr: hmm whats a 2222 rated to...
05:10 PM rue_mohr: 250
05:10 PM rue_mohr: hmm
05:13 PM polprog: hmm, i could try with 2n2222
05:13 PM rue_mohr: no its awefull
05:13 PM rue_mohr: find a computer CRT monitor that uses transistors in its video path, they are rated 2Ghz
05:14 PM polprog: i have some RF NPNs, BFX59
05:14 PM rue_mohr: and IT MAKES A DIFFERENCE!
05:14 PM polprog: 1GHz
05:14 PM rue_mohr: I think I was playing with some switching stuff, and I was amazed
05:14 PM Tom_L: what about the silicon determines it's operating frequency?
05:15 PM rue_mohr: dunno
05:17 PM polprog: me neither
05:17 PM polprog: maybe stray capacitances
05:17 PM polprog: idk
05:17 PM polprog: allright, ill try to test the oscillator tomorrow :)
05:17 PM polprog: gn
05:18 PM Tom_L: so you say
08:40 PM rue_mohr: http://www.dicks-website.eu/fetosc/enindex.htm
09:23 PM Tom_L: there was a trick to the lettering i'd forgoten
09:24 PM Tom_L: you gotta do it in the drafting mode not sketcher
09:24 PM Tom_L: then you save it as a dxf and paste it into the sketch. that turns the letters into polylines which then can be extruded
10:40 PM rue_mohr: :)
11:22 PM aandrew: I'm up at a cottage in the ottawa valley
11:23 PM aandrew: about 30m from where my grandfather's farm was
11:23 PM aandrew: (on Kohlsmith road, my surname, incidentally)
11:23 PM aandrew: I feel quite strongly that I might just move up here once my immediate famillial responsibilities are met
11:23 PM aandrew: little house with a workshop in the middle of fucking nowhere
11:24 PM aandrew: thankfully my employment needs are largely geographically independent although I'm about an hour from Ottawa which has a fairly high-tech sector
11:24 PM aandrew: heat would likely end up being wood/propane, and internet almost certainly starlink
11:25 PM aandrew: I'm gonna see if I can't arrange a road trip with my dad and all my sons just for fun in the next year
11:25 PM aandrew: think it might be kind of cool to have 3 generations
11:25 PM aandrew: sadly my grandfather died like 20+y ago
11:26 PM aandrew: he'd have loved to have met his great grandkids
11:26 PM aandrew: that's probably the biggest thing I'm fighting... trying to make sure I'm not just wanting to move way the fuck up here with nobody around me just because I'm feeling nostalgic
11:40 PM rue_mohr: why do they all sell the farms
11:43 PM aandrew: well
11:43 PM aandrew: my grandfather died
11:43 PM aandrew: I was -->||<-- that close to buying it when i was 17
11:43 PM aandrew: or at least trying to
11:44 PM aandrew: there aren't many jobs up here
11:44 PM aandrew: largely drinking culture
11:44 PM aandrew: not a great place to move as a young'un nor to raise young'uns
11:44 PM aandrew: but not a bad place at all to "retire"
11:45 PM aandrew: and i think it'd be pretty fucking amazing to either buy his old farm (it's not currently up for sale) or buy a place on Kohlsmith Rd. :-)
11:45 PM aandrew: dunno though
11:45 PM aandrew: half my kids are grown adults and the others are getting there but still a ways to go
11:45 PM aandrew: I wouldn't leave them anytime soon
11:45 PM aandrew: but after they're grown.... why not
11:46 PM aandrew: my wife, likely ex wife before then, would be welcome to visit, but I seriously doubt any real retirement or future with her
11:47 PM aandrew: nothing malicious, but I know I'm rapidly sick of the BS and I know she feels the same
11:48 PM aandrew: this cottage is basically one large area, about 30' x 15' with a kitchen on one end and couch on the other, and then another 10' or so along that long wall with three rooms and a bath
11:48 PM aandrew: it's damn near perfrect for a single guy who just needs a bit of space, an office and bedroom
11:49 PM aandrew: throw a 30x30 workshop beside it, ideally connected to it and that's pretty much perfect
11:49 PM aandrew: think your place, rue_mohr