#garfield Logs
May 15 2021
#garfield Calendar
12:00 AM rue_mohr: I am having a really hard time getting myself to do anything latley
12:13 AM rue_mohr: hahah
12:13 AM rue_mohr: youtube wont let me delete a video with any of the browsers I have
12:13 AM rue_mohr: dare I use an online browser to do it?
12:33 AM rue_mohr: https://www.youtube.com/watch?v=Q1AJrLTZ4Yo
12:38 AM rue_mohr: polprog, I dont see where the module gets its power (the creative board)
01:39 AM polprog: morning
01:40 AM polprog: rue_mohr: there was a molex floppy drive header but i removed that and stuck a 7805 with a dc jack on it.
01:41 AM polprog: i think i had just one clip where i solder it in and i didnt film that
01:54 PM rue_mohr: morning
01:54 PM rue_mohr: :)
02:34 PM Tom_L: yeah
02:50 PM rue_shop1: so, I wonder if the mowerbots batteries are still ok
02:50 PM rue_shop1: oh battery
02:50 PM rue_shop1: ok
02:51 PM rue_shop1: 7.8V is not good
02:51 PM rue_shop1: implies its only got 4 working cells
02:52 PM rue_shop1: heavy charge current is a good sign
02:53 PM rue_shop1: the amount of aluminum I have for casting is stupid
02:59 PM rue_shop1: jumped to 14.6 pretty fast
03:00 PM rue_shop1: Tom_L, cnc router
03:00 PM rue_shop1: what do you think is the max reasonable precsiion
03:00 PM rue_shop1: were talking wood
03:00 PM rue_shop1: 0.1mm?
03:01 PM Tom_L: depends on your abilities and construction methods
03:02 PM Tom_L: for that big one?
03:02 PM rue_shop1: yea
03:02 PM rue_shop1: but wood in general
03:02 PM rue_shop1: it breathes a lot
03:02 PM rue_shop1: there is no point machining it to 1 thou
03:02 PM rue_shop1: or below
03:07 PM rue_shop1: ditto plasma cutter for different reasons
03:07 PM rue_shop1: when your cutter is +- like 1mm from where you put it
03:07 PM rue_shop1: maybe more
03:10 PM rue_shop1: I suppose the start of breaking down is to cast/machine V sleeves for the 608 bearings
03:51 PM polprog: hello rue
03:58 PM rue_mohr: hi
05:34 PM polprog: plan for the next evening
05:34 PM polprog: https://www.nxp.com/docs/en/application-note/AN238.pdf
05:43 PM polprog: rue_mohr: got LTspice?
05:47 PM aandrew: RF electronics always makes my mind wilt
05:53 PM polprog: you tell me
05:53 PM polprog: i just now realized that i hve to multiply instead of adding >:)
05:54 PM polprog: becasue of course sina * sinb is the right formula
05:54 PM rue_mohr: i dont
05:54 PM polprog: it's a nice program
05:54 PM polprog: free
05:54 PM rue_mohr: linux?
05:55 PM rue_mohr: did you see the logic gate mixer?
05:55 PM rue_mohr: or was that a discriminiator
05:55 PM polprog: logic cate mixer
05:55 PM polprog: gat*
05:55 PM polprog: ugh
05:56 PM polprog: to be frank if you treat an inverter as an amplifier and use the transimpedance topology it could work
05:57 PM polprog: 1st picture
05:57 PM polprog: https://www.electronics-notes.com/articles/radio/rf-mixer/bipolar-transistor-mixer.php
05:58 PM polprog: The "LO to base, RF to emitter" could be done using the inverter input as the base and feeding the RF into the grund pin hahaha
06:00 PM polprog: doesnt that BJT need some power at the collector or did they just omit that
06:03 PM rue_mohr: https://acidbourbon.wordpress.com/2021/04/11/a-74xx-defined-radio/
06:03 PM polprog: dang, they were first :<
06:03 PM rue_mohr: you didn't catch it on twitter?
06:04 PM rue_mohr: maybe I generate too much like-noise
06:04 PM polprog: now i look at that schem and i think i saw that
06:04 PM polprog: yeah i saw it but i didnt catch how it works
06:09 PM rue_mohr: stuff two freqs into an XOR, the result is pwm :)
06:09 PM rue_mohr: not the same, but cool
06:09 PM polprog: heh
06:09 PM polprog: i should build a boost for 33V for the modulator/demod cans
06:09 PM polprog: if i could get the one with i2c going that would be kewl
06:09 PM polprog: poor mans radio
06:09 PM rue_mohr: haha after me building a 555 based 700V boost yesterday
06:10 PM polprog: haha maybe something
06:10 PM polprog: hmm
06:10 PM polprog: not a bad idea
06:10 PM polprog: was that flyback?
06:10 PM rue_mohr: you can scale it down
06:10 PM rue_mohr: yes
06:10 PM polprog: welcome to polprogs bench, where every boost converter is flyback
06:10 PM rue_mohr: from 12V, but it had no problem generating 90V from 5
06:10 PM polprog: watching 12voltvids repair a tv set
06:11 PM polprog: yeah i need 33V and stabilized, so id probably throw some feedback onto it, if you didnt have it
06:11 PM rue_mohr: it does
06:11 PM polprog: i just skimmed thru, i have loads of bs work
06:11 PM rue_mohr: https://twitter.com/RueNahcMohr/status/1393403106109497345/photo/1
06:11 PM rue_mohr: change the zener for whatever you want
06:11 PM polprog: ah i remember
06:11 PM rue_mohr: even in that config, I could put a 24V zener in and get 24V
06:12 PM rue_mohr: the 2n2222 is a shutdown regulator
06:12 PM rue_mohr: the 2N7000 prevents shutdown DURING a pulse (which screws up the switching)
06:13 PM rue_mohr: the fitler on the 555 power was required!!!
06:13 PM rue_mohr: the 10k pullup on reset was not
06:13 PM polprog: heh
06:14 PM rue_mohr: open loop, it shoudl generate about 12kHz, about 40% duty
06:14 PM polprog: smart with that 2n7000
06:14 PM rue_mohr: neither is critical
06:15 PM rue_mohr: and you cant overload it
06:15 PM rue_mohr: it'll just duck out
06:15 PM rue_mohr: that is to say "it cant be overloaded"
06:15 PM polprog: i wonder if i should get a head on magnifier
06:16 PM rue_mohr: I need to make a cap bank
06:16 PM polprog: the chip hooks on these i2s ICs on the soundblaster were pretty hard to spot right
06:16 PM polprog: and the adjustable magnifier on the stand was pretty finnicky to use
06:16 PM rue_mohr: xy table and a toy usb microscope
06:16 PM rue_mohr: ;)
06:17 PM polprog: for working on stuff, not for looking at stuff
06:17 PM polprog: that too
06:17 PM polprog: a metallurgical microscope would be awesome
06:17 PM polprog: or a regualr optical one
06:17 PM polprog: but a proper, not a toy one
06:17 PM polprog: they are too expensive tho
06:17 PM rue_mohr: its still sunny, I'm gonna go try to be outside
06:18 PM polprog: have fun
06:19 PM polprog: play catch with the mowerbot
06:22 PM polprog: how cool is that
06:22 PM polprog: i should get a tiny tv
06:22 PM polprog: like 14", and make it into a cvbs display
06:22 PM polprog: i wonder if i could retune the horizontal scan frequency to match the nonstandard video output from my spectrum analyzer...
06:23 PM polprog: or just to have a regular display for the pi
06:23 PM polprog: but i dont have space for a 14" box
06:39 PM polprog: i should take a look at my CRT, its a bit dim
06:39 PM polprog: even on 800x600
06:40 PM polprog: and preactically unreadable at native resolution...
06:40 PM polprog: i wonder why, maybe i just need to crank up the eht adjust
06:40 PM polprog: forgot the name
06:43 PM rue_shop1: backlight or contrast?
06:47 PM polprog: contrast
06:47 PM polprog: or rather.. white letters are barely visible
06:48 PM polprog: like, linux tty at native resolution (1600x1200)
06:48 PM polprog: cant see anything
06:50 PM polprog: Adjust CDT Anode voltage to 26kV ± 0.2kV with
06:50 PM polprog: hmm, i wonder if i can measure that
06:51 PM polprog: i have no idea how old the tube is, but this was pulled from the collection at grandmas house, someone just carried it down there
06:51 PM polprog: so it was from a house, probably not running 24/7
06:53 PM polprog: i have the service manual with full schematics <3
07:15 PM rue_shop1: this spot welder would be easier if I'd been able to start with any part ready and working
08:48 PM aandrew: hm, I didn't think I had that big a muslim population near me, but there's all kinds of fireworks going off, presumably for Eid
08:48 PM aandrew: I know there's a neighbourhood a couple km away that's got a LOT of indian/sikhs but didn't think there were many muslims around
08:49 PM Tom_L: ok. finally got the pc back
08:50 PM Tom_L: or my office rather..
09:09 PM Tom_L: https://hackaday.com/tag/wire-bender/
09:26 PM rue_shop1: whats this one like...
09:32 PM aandrew: interesting, not a super bender but good for making custom and unusual springs
09:32 PM aandrew: https://howtomechatronics.com/projects/arduino-3d-wire-bending-machine/ is better I think
09:35 PM Tom_L: i think that one is shown at the bottom of the hackaday article
09:35 PM Tom_L: or midway
09:36 PM aandrew: yep it is
09:36 PM aandrew: it's the second one in the hackaday link you pasted
09:37 PM aandrew: I should hunt around for a wire cutting/stripping machine. I loved that zeittberg or zettler or whatever one that car-san had.
09:39 PM rue_shop1: I thik I saw that one
09:42 PM aandrew: heh first hit on google: https://www.youtube.com/watch?v=Jl6ZATZypAQ
09:46 PM aandrew: https://www.youtube.com/watch?v=WVnbbqSEDU0 is a lot closer to the one I used, including the blades
09:46 PM aandrew: the commercial machine used two "tracks" to grab and move the wire around so it had a lot better grip, and it also had a straightener in front of it
09:49 PM aandrew: https://www.youtube.com/watch?v=xZfV_YZVd1s is pretty much the exact unit I used
09:56 PM rue_shop1: why does it have two ethernet jacks?
09:57 PM Tom_L: double the throughput
09:57 PM Tom_L: ?
09:59 PM rue_shop1: interesting how everyone is using V cutters
09:59 PM Tom_L: for wire cutters?
09:59 PM Tom_L: i didn't watch the yt
10:02 PM rue_shop1: you know, if I just had a mchine to strip the ends when I push them In I'd be happy
10:05 PM aandrew: yeah I have no idea on the double ethernet
10:05 PM aandrew: I think V cutters are just easy to get, and you can cut enough of the insulation that it easily pulls apart
10:06 PM Tom_L: do they enter the wire size so the v cutter doesn't nick the wire?
10:06 PM aandrew: man I replaced the gasket on my little moka pot (old one must be a year old) - holy shit what a difference that made :-)
10:07 PM aandrew: the one I used yes - you specified both the gauge of the wire and thickness of insulation
10:07 PM aandrew: I bet it could properly strip quad shield coax if you entered all the parameters
10:07 PM Tom_L: wonder how it does on teflon
10:08 PM aandrew: indeed; I was just cutting regular old wire
10:11 PM aandrew: heh
10:11 PM aandrew: https://www.aliexpress.com/item/1005002316848877.html watch the video there
10:11 PM aandrew: scary machine
10:13 PM aandrew: wish this had a video, I'd like to see that work: https://www.aliexpress.com/item/1005001411777621.html
10:14 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/JT-SHOP/model.jpg
10:14 PM Tom_L: making an assembly fixture for that
10:14 PM aandrew: oh
10:14 PM aandrew: https://www.youtube.com/watch?v=oHb3BZIGyHI
10:14 PM aandrew: not as impressive as I'd hoped
10:15 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/JT-SHOP/profile1.jpg
10:15 PM Tom_L: that's what that is for
10:16 PM aandrew: and holy fuck, https://www.youtube.com/watch?v=DQr6QwacJHQ is just begging to eat fingers
10:17 PM Tom_L: he looks like he's missing a few parts anyway
10:17 PM aandrew: 10/10 for enginuity though
10:18 PM rue_shop1: one of the guys at our copany paid $700 for a stripper
10:18 PM Tom_L: was she any good?
10:18 PM aandrew: bet it doesn't have as many OHSA violations as that video :-)
10:18 PM aandrew: lol Tom_L
10:19 PM aandrew: reminds me of that line on the movie dodgeball
10:19 PM Tom_L: he must be just salvaging the copper
10:19 PM aandrew: "the stripper was meant to be congratulatory" "it was also a man"
10:19 PM rue_shop1: its just a right angle gear motor on a stand with a blade and a speed controo
10:20 PM rue_shop1: told him I'd have sold him one for only $500
11:33 PM rue_mohr: a bit of work on the 4x8 cnc today
11:34 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1190598.jpg
11:35 PM rue_mohr: shapeloc to try to get the profile of the router
11:40 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1190600.jpg
11:40 PM rue_mohr: some different options for driving Z
11:41 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1190601.jpg
11:41 PM rue_mohr: I found a drive rod and some sprockets for the X axis
11:45 PM rue_mohr: I'm not sure if I should put the drive motor on the bed and fix the chain to the carriage, or if I should fix the chain to the bed and put the motor on the cariiage