#garfield Logs

Aug 08 2020

12:16 AM rue_mohr: ouch
12:22 AM rue_mohr: alternating channels?
02:29 AM zhanx_workshop: ok hard wired noq
02:30 AM zhanx_workshop: now with a new keyboard
02:31 AM polprog: what are you building with these 6002 opamps, rue?
02:32 AM polprog: hi zhanx
02:32 AM zhanx_workshop: hey polprog
02:33 AM polprog: today evening im back at my workshop/bedroom :)
02:35 AM zhanx_workshop: i attempted the wifi relay but hardwired it instead
02:37 AM polprog: as in both APs are connected over a wire?
02:37 AM zhanx_workshop: now yes
02:37 AM zhanx_workshop: POE
02:39 AM zhanx_workshop: update time
03:20 AM rue_bed2: polprog, power supply
03:23 AM zhanx_workshop: rue_bed2, i had to hardwire the shop
05:08 AM zhanx_workshop: ok cement work done
06:09 AM Tom_L: i put a wifi relay in the garage a while back but i've still got hardwire out there
08:33 AM polprog: rue_bed2: these opamps drew my attention, are these just garden variety or some special?
08:33 AM polprog: ive seen they are up to 1MHz
11:42 AM rue_bed2: polprog, their rail to rail
11:42 AM rue_bed2: input and output
11:42 AM rue_bed2: I have two that I like
11:43 AM rue_bed2: mcp6002 and LM6842 (I think)
11:43 AM rue_bed2: one of them can only go to 5V
11:43 AM rue_bed2: the other can take like 15
11:43 AM rue_bed2: but both rail-rail
11:44 AM rue_bed2: in contrast, the LM741 can barely get to within 3V of its power rails
11:44 AM rue_bed2: aka not much left if your trying to run it on 5V
11:44 AM rue_bed2: most op-amps have lots of overhead that way
12:40 PM rue_mohr: damn, its too easy to catch up with whats going on on twitter
12:40 PM rue_mohr: ok, its 10:40
12:41 PM rue_mohr: maybe if I do branch chipping for a while I"ll think of what to do
12:41 PM rue_mohr: oh the power supply
12:41 PM rue_mohr: ok, I need breakfast/shower
02:03 PM Tom_L: half the day is gone
02:11 PM rue_mohr: oops
02:26 PM Tom_L: figuring out the cutter holder
02:45 PM rue_mohr: recycling, bbl
02:52 PM polprog: damn, they are nice indeed
02:53 PM polprog: good to be back. i have to declusterfuck the room
02:53 PM polprog: i think the thin clients will go to the basement, and i have to reorganize the books
02:56 PM polprog: oh wow. one of the unusual uses for the reset IC i posted (M51957) - 5uA current source on pin 4
03:06 PM rue_mohr: :) nice
03:07 PM polprog: jus ran a job on the dot matrix printer
03:07 PM polprog: the datasheet i posted on twitter, just to have it to scribble on
03:07 PM rue_mohr: hahah did you get it going as an oscillator?
03:07 PM polprog: not yet
03:07 PM polprog: dad just came in and said "Im going to sleep, please dont print anything tonight"
03:07 PM polprog: the pins of the SIP are too short for the breadboard
03:10 PM polprog: its B, the open drain version
03:10 PM rue_mohr: use machined header strip
03:10 PM rue_mohr: or solder a header to it
03:10 PM polprog: just did dthat
03:11 PM polprog: it is alive thats for sure
03:11 PM polprog: reacts as intended
03:11 PM rue_mohr: I got a bunch of old hard drives delivered to the e-waste centre
03:11 PM polprog: imma turn the analog scope on...
03:11 PM rue_mohr: which is good, helping to clear things off the deck
03:11 PM rue_mohr: if kiwa wants those drives it'll help too
03:11 PM rue_mohr: a bit
03:11 PM polprog: isnt he in south america?
03:11 PM rue_mohr: yea
03:12 PM rue_mohr: I sent him some ram sticks once
03:12 PM rue_mohr: :D
03:12 PM rue_mohr: 30 pin
03:12 PM polprog: neat
03:12 PM polprog: dosfox sent me a mpeg decoder card
03:12 PM rue_mohr: the drives would be a bit more shipping, see if he wants to kick in for it
03:12 PM rue_mohr: hey, that image for the pal software
03:12 PM rue_mohr: is it good?
03:13 PM polprog: i think it is
03:13 PM polprog: i havent tested it on bare metal yet
03:13 PM polprog: i dont have the pals yet either
03:13 PM rue_mohr: I want to put it on a disk and boot something
03:13 PM polprog: yeah. do that please
03:13 PM rue_mohr: I dont have a pal programmer
03:13 PM polprog: huh
03:13 PM rue_mohr: half the challenge seems to be to make the file
03:13 PM polprog: there are partport ones...
03:13 PM polprog: parport*
03:15 PM rue_mohr: w/ diy schematics?
03:15 PM polprog: yeah
03:15 PM polprog: i think i saw one
03:15 PM polprog: hmm
03:16 PM polprog: so this thing closes the open drain output when power is good. So i get 5V at the output when power is good
03:16 PM polprog: power good is 5V on the input
03:16 PM polprog: :( i need a transistor
03:19 PM polprog: it oscilaltes
03:19 PM polprog: makes a puilse train
03:19 PM polprog: ugh
03:19 PM polprog: cant type with my hands raised
03:28 PM rue_mohr: hm
03:33 PM polprog: 44 minutes
03:33 PM polprog: :P
03:34 PM polprog: remind me not to do schems in pen anymore
03:34 PM rue_mohr: hmm
03:35 PM polprog: different cap gives different intervals
03:36 PM rue_mohr: thats good...
03:36 PM rue_mohr: did you make it a relaxation osc?
03:36 PM polprog: no, i dont think so
03:36 PM polprog: however
03:36 PM polprog: actually i think it is
03:36 PM rue_mohr: ground itself out when it gets up to votlage?
03:37 PM polprog: yeah
03:37 PM polprog: funny enough it seems to be happy with just the breadboard capacitance at the cap pin
03:38 PM rue_mohr: heh, I suppose you can do that with a 555 too.
03:38 PM polprog: which makes it run at 6khz that way
03:38 PM polprog: not the fastest thing, but the 4n33 isnt either
03:38 PM rue_mohr: hahah
03:39 PM rue_mohr: no comments from peanut gallery! we makin oscillators out of EVERYTHING
03:39 PM rue_mohr: :)
03:39 PM polprog: :P
03:39 PM polprog: peanut gallery :P ?
03:39 PM rue_mohr: watchers
03:39 PM polprog: ah
03:40 PM rue_mohr: going to go do things, biab
03:40 PM polprog: cya
03:44 PM polprog: ill head to the bed
05:57 PM rue_shop1: damnit, I forgot to get the mortar for the driveway pillars
05:58 PM rue_shop1: and the parts for fixing up the cement mixer
05:59 PM rue_mohr: and a new tarp for the table saw
06:00 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/Broach/Broach_holder1.jpg
06:01 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/Broach/Broach_holder2.jpg
06:01 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/Broach/Broach_holder3.jpg
06:01 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/Broach/Broach_holder4.jpg
06:01 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/Broach/broaching1.jpg
06:01 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/Broach/broaching2.jpg
06:01 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/Broach/broaching3.jpg
06:01 PM Tom_L: end run.
06:02 PM rue_mohr: polprog, why did you put the onto in there?
06:02 PM rue_mohr: heh thermal printer
06:03 PM rue_mohr: Tom_L, did you catch a video?
06:03 PM Tom_L: no
06:03 PM rue_mohr: heh, nice retainer
06:04 PM rue_mohr: did the process go pretty smooth?
06:04 PM Tom_L: i may add another screw or a dowel pin to keep it located
06:04 PM Tom_L: yeah
06:04 PM rue_mohr: cool
06:04 PM rue_mohr: what step size?
06:04 PM Tom_L: manual :)
06:04 PM rue_mohr: ?
06:04 PM Tom_L: i tried .005" and it seemed ok
06:04 PM rue_mohr: 5 thou?
06:04 PM rue_mohr: haha
06:05 PM Tom_L: at least it doesn't push back in the holder now
06:05 PM Tom_L: it's possible it is moving down a tiny bit in front. that's why i may add another screw
06:06 PM Tom_L: it was crap i had sitting on the bench so i tried it
06:11 PM rue_mohr: yea
06:11 PM rue_mohr: test
06:13 PM Tom_L: gonna go finish cutting it now and see how it does
08:18 PM rue_mohr: ok, did up a few more tubes for sprayers
08:20 PM Tom_L: i was thinking how easy it would be to cut those on the rotary
08:20 PM Tom_L: the slot
08:20 PM Tom_L: i forgot how you did it
08:34 PM rue_mohr: router
08:34 PM rue_mohr: the thin slot in the end of the pipe is via table saw with carefully calibrated jig and blade
08:35 PM rue_mohr: http://www.ruemohr.org/p1080919.jpg
08:35 PM rue_mohr: that the sheet metal slides into
08:35 PM Tom_L: yeah
08:35 PM Tom_L: i bet that's noisy to cut
08:35 PM rue_mohr: the router, yes
08:36 PM rue_mohr: the thin slot no
08:36 PM Tom_L: do you mount the router on a table or freehand it?
08:36 PM rue_mohr: you can barely make out the blade doing the cutting
08:36 PM rue_mohr: I have a jig for the router table
08:36 PM rue_mohr: its totally taking over my router table
08:36 PM Tom_L: i don't use my router very much
08:37 PM Tom_L: i did put a new bearing in it several years back
08:37 PM rue_mohr: me either
08:37 PM rue_mohr: I thought a router table would be nice, we needed one for the spryaers so I made it
08:37 PM Tom_L: i don't think i'm gonna broach much on the mill. i think it's too hard on it
08:37 PM rue_mohr: i guess the same bits could be used in the cnc with a jig
08:38 PM rue_mohr: its probably the most force youve applied to the axis
08:38 PM Tom_L: no doubt
08:38 PM Tom_L: twice i've pushed the work back in the chuck
08:38 PM rue_mohr: you didn't shoulder it up against the back?
08:39 PM Tom_L: no i wanted it sticking out so i could center the tool against it using the edge
08:39 PM rue_mohr: I think using the z axis would have been better
08:39 PM Tom_L: maybe, i dunno
08:39 PM Tom_L: it's got more force
08:40 PM Tom_L: due to the pulley reduction
08:40 PM rue_mohr: and gravity
08:40 PM rue_mohr: most of the helft of the cut would probably be covered by the head weight
10:05 PM Tom_L: it's hard to find motor specs for the sherline motor
10:06 PM Tom_L: but aparently it's only 60w
10:09 PM Tom_L: i thought it was more
10:10 PM Tom_L: so maybe that 750w motor i was looking at would be enough instead of the 1.2kw one
10:10 PM Tom_L: that would save me wiring 220v to it
11:58 PM zhanx_workshop: rue_mohr, dumb question
11:59 PM zhanx_workshop: can i earth ground my shop and call it good or do i need to rerun the wire with a ground to the service