#garfield Logs

Mar 05 2020

#garfield Calendar

12:00 AM polprog: buy pot (1k linear, 10k linear)
01:30 AM rue_bed: na, you just need an adjustable voltage around the 3.3 mark
01:30 AM rue_bed: log or linear doesn't matter
01:31 AM rue_bed: it looks like when its gonna oscillate, it does
01:31 AM rue_bed: its backwards eh?
01:31 AM rue_bed: it triggers when the cap voltage is too low
01:31 AM rue_bed: so it naturally starts on power up
01:32 AM rue_bed: the active component charges the cap, not discharges it, thats why I said its an anti-relaxation osc
01:32 AM rue_bed: in a relaxation osc, the active component discharges the cap, its charged by a resistor
01:33 AM rue_bed: this thing is discharged by resistor
01:33 AM rue_bed: the cathode going low enough makes the gates "static" voltage high enough to trip the scr, which continues to conduct untill the current drops too much
01:34 AM rue_bed: its, of course charging a cap, so at some point the differential voltage between the supply and the cap isn't sufficient to maintain the current
01:34 AM rue_bed: the charge rate being limited by that 560 ohm resistor
02:01 AM polprog: i have adjustable voltage between 0-5V but i couldnt get it to oscillate
02:02 AM polprog: iirc they need a minimal current to maintain
02:02 AM polprog: what i got was the cap voltage closely following the gate voltage
02:06 AM polprog: if i put a resistor on the gate, i also had that behavior but the gate voltage range was smaller (drop on resistor)
10:45 AM polprog: ofc thyristors are current controlled!!
10:45 AM polprog: ive got a gate trigger current here (BT151 - i bought 4 today) of 2mA typ, 15mA max
10:46 AM polprog: ill have to find out the trigger current of the TC-100 soviet one..
11:26 AM polprog: oi!
11:26 AM polprog: i got it to oscillate
11:27 AM polprog: the cap discharge resistor needs to be small enough to actually turn the thyristor on!
11:27 AM polprog: otherwise its just the gate current charging the cap
11:27 AM polprog: rue_bed: !!!
11:40 AM polprog: but i need an additional diode
11:55 AM polprog: oh.. it also oscillates without the 22n cap
12:05 PM Tom_L: breadboard?
12:05 PM Tom_L: probably capacitance on the breadboard itself
12:05 PM polprog: possible
12:06 PM polprog: its extremely unstable
12:39 PM polprog: putting my hands over the probe wires makes it all wonky
01:44 PM polprog: https://polprog.net/rozne1/ircjunk/thyrosc/
01:57 PM polprog: so the big soviet one has a golding current of 250mA
02:00 PM polprog: holding current*
02:00 PM * polprog shakes rue_bed
03:23 PM zhanx_ is now known as zhanx
07:11 PM rue_mohr: polprog, when you origionally made it, did you have the 47k resistor on the gate?
07:12 PM rue_mohr: yea, mine was pretty unstable too, oscillating, but lots of noise
07:13 PM rue_mohr: :) ool
07:13 PM rue_mohr: cool
07:14 PM Tom_L: is there virus madness up there too?
07:14 PM rue_mohr: everywhere is out of rubbing alcohol
07:14 PM Tom_L: and hand sanitizer...
07:14 PM rue_mohr: its polen season, so, I'm starting to have usual issues
07:15 PM rue_mohr: I dont react to the polen, I have issues with the volumes of it
07:15 PM Tom_L: yeah, i didn't used to but now i do
07:15 PM rue_mohr: its the volumes of polen
07:15 PM rue_mohr: there is a coating of it on my truck
07:16 PM Tom_L: where we're going it turns everything yellow
07:16 PM rue_mohr: yup
07:16 PM rue_mohr: its mostly aldar polen right now
07:17 PM Tom_L: i'm not sure what they have
07:17 PM Tom_L: way past where kat lives
07:17 PM rue_mohr: I think today was a waste in almost every way
07:18 PM Tom_L: i'm sure of it
07:18 PM Tom_L: kid ran over a couple nails in his new car and cost me a $200 tire
07:18 PM rue_mohr: his you?
07:18 PM rue_mohr: his himself
07:19 PM Tom_L: yes
07:19 PM rue_mohr: car = expenses, pay for it yourself
07:19 PM Tom_L: i covered it
07:19 PM rue_mohr: ?
07:19 PM rue_mohr: hmm
07:19 PM Tom_L: he helps out around here
07:19 PM Tom_L: both do
07:19 PM rue_mohr: good show
07:19 PM Tom_L: but it was still a pisser
07:24 PM rue_mohr: tom di you see the bender?
07:53 PM Tom_L: no
07:53 PM Tom_L: not that i know of anyway
07:54 PM Tom_L: now i did
07:56 PM Tom_L: how did the stubby sharpies work out?
08:04 PM rue_mohr: didn't try yet
08:04 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1150400.jpg
08:05 PM Tom_L: yeah
08:56 PM rue_bed: thoughts
08:57 PM rue_bed: ?
09:00 PM Tom_L: not enough pics or details
09:01 PM Tom_L: looks functional though
09:03 PM rue_bed: bends seem to be comming out a bit soft
09:03 PM rue_bed: not sure if I need to do it differently
09:03 PM Tom_L: is the angle iron radius'd in the ID?
09:04 PM rue_bed: wow, stress kills me for the day
09:04 PM Tom_L: might need to weld 2 plates to get the 90 instead for a sharp corner
09:04 PM rue_bed: I took an angle grinder and ground the angle iron
09:04 PM rue_bed: right took for hte right job, right?
09:04 PM rue_bed: I kinda think I might have warped it
09:05 PM rue_bed: I can check if I get n r g to get out of bed
09:07 PM rue_bed: I need to be a robot
09:08 PM Tom_L: you'd better invest in better batteries before
09:08 PM rue_bed: yea
09:08 PM rue_bed: worried I'm not in good habbit to charge them when they need it
09:11 PM Tom_L: you'd better have a backup plan for that one
09:13 PM rue_bed: I been trying to figure out how much of my inability to get up and do things is mental
09:13 PM rue_bed: I can kinda tell melatonin
09:13 PM rue_bed: not sure on the other bits
09:14 PM Tom_L: the ones from target are the best
09:14 PM Tom_L: do you have target?
09:15 PM rue_mohr: no
09:15 PM rue_mohr: not what i'm saying
09:15 PM rue_mohr: after taking melatonin, I can tell when I get hit by my own
09:16 PM rue_mohr: but there is other stuff going on that makes me tired
09:19 PM Tom_L: i haven't done anything i'd call productive since the mill build
09:41 PM rue_mohr: with summer comes inspiration
10:23 PM zhanx: well tonight sucks
10:51 PM rue_shop1: do tell z
11:01 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1150402.jpg
11:01 PM zhanx: my grandfathers lawyer called me
11:02 PM rue_mohr: oh no
11:02 PM zhanx: he is on his death bed
11:02 PM rue_mohr: ouch
11:02 PM zhanx: since i am the sole etc
11:02 PM rue_mohr: can/doyou want to go see him?
11:02 PM rue_mohr: oh
11:02 PM rue_mohr: you got a lot to deal with
11:02 PM zhanx: i can't afford to
11:02 PM zhanx: but he is bill gates rich
11:03 PM rue_mohr: can afford to see him or have him die
11:03 PM rue_mohr: so his passing will cost a fortune?
11:03 PM rue_mohr: I hear it goes bad in the states
11:03 PM zhanx: beats me, i am would rather he live then have a dollar
11:03 PM rue_mohr: yea
11:03 PM rue_mohr: did he build stuff?
11:04 PM zhanx: ford CEO for 50 years
11:04 PM rue_mohr: !woof
11:04 PM rue_mohr: did he go up or start at the top
11:04 PM zhanx: bottom up
11:04 PM rue_mohr: cool
11:05 PM rue_mohr: so is he in the usa?
11:05 PM zhanx: i am the only grandson not to be on his belt loop etc
11:05 PM zhanx: yes
11:05 PM rue_mohr: well, what would it take to go see him?
11:05 PM zhanx: i thought I was getting some guns etc
11:06 PM rue_mohr: drivable or fly thing?
11:06 PM zhanx: a time machine now
11:06 PM rue_mohr: oh, he did pass? is passing?
11:06 PM rue_mohr: :S
11:07 PM zhanx: he was the only one when i earned my green beret to care
11:07 PM rue_mohr: :)
11:07 PM rue_mohr: so he was in contact
11:07 PM zhanx: he was a man of very very few words
11:08 PM rue_mohr: hm
11:08 PM rue_mohr: special family trip once every x years kinda relationship?
11:08 PM zhanx: remember back in 08 when i freak out due to my cousin dying?
11:08 PM zhanx: when i went postal etc
11:09 PM rue_mohr: its a bit of a blur, there was a lot going on a few times
11:09 PM zhanx: he never forgot that
11:09 PM rue_mohr: you live a bumpy life
11:09 PM zhanx: yep
11:18 PM zhanx: should just stop that
11:18 PM zhanx: be easier and less painful
11:19 PM rue_mohr: its not always dialable
11:19 PM rue_mohr: I was told today that all my going-on about domains and servers and software was over-complexifying our email system
11:21 PM rue_mohr: and I guess thats it, I make things complicated
11:22 PM zhanx: i was planning on going to SpaceX tomorrow they are highering like crazy now
11:22 PM rue_mohr: that would be cool