#garfield Logs

Feb 15 2014

02:57 dumbass-afk the original url : news.discovery.com/human/health/brest-milk-varies-for-males-females-140214.htm
02:57 dumbass-afk the new url : http://news.discovery.com/human/breast-milk-varries-for-males-and-females-140214.htm
02:57 dumbass-afk they cannot spell the simplest words, and cannot use a spell checker
14:50 rue_house http://electronics-diy.com/schematics/1185/30V-10A-Variable-Bench-Power-Supply-circuit.jpg
14:50 rue_house I could put a switching back end on it
15:47 dumbass-afk 3055's are dead slow, yanno
15:48 dumbass-afk what a wierdly drawn schematic
16:06 rue_shop2 my idea was to remove all the 3055, and replace it all with a pwm buck converter
16:06 rue_shop2 remember, I'm going for switching on this
16:06 dumbass-afk you you will keep the line on the paper in place, and change ut all the parts and their functions?
16:08 mbass-afk points out that out in the field, 40+ yrs ago, switching psu was discovered when new high freq parts were used in regular circits that had too much positive feedback, and they oscill
16:10 dumbass-afk it's possible, if you add too much lead inductance (or a small choke) to the pass transistor (or fet), it will oscillate nicely, especially if you replace the 3055's and the lil driver with a pnp transistor and the chokes on the emitter, and make sure you drive it with a square wave
16:12 dumbass-afk another option is replace the opamp used for voltage sense with two comparators: the volts are either to low so turn on the pass transistor, or too high so turn it off
16:19 dumbass-afk modern switchers can get complicated
16:19 dumbass-afk they don't get more efficient in the real world, just more complicated
16:22 rue_shop2 kat, do you know whwere I can find specs for E clips?
16:23 dumbass-afk no
16:23 rue_shop2 I just get themout of stuff, dont knwo who sells them
16:23 dumbass-afk Fastanl does, but i don't have specs
16:23 dumbass-afk fastenal
16:23 dumbass-afk mouser prolly does
16:23 rue_shop2 mouser? e clips!?
16:24 dumbass-afk i seent hem on ebay
16:24 dumbass-afk but no specs
16:24 dumbass-afk praps we don't mean the same thing by "e clips", what do you mean?
16:25 rue_shop2 look like a C but with a nub on the inside back
16:25 dumbass-afk oh, for shafts?
16:25 rue_shop2 https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcS_jmw9Mv9nH0cNCcUHd63waIXjSeWv1ZUlhrMQKbwdp6kkhThd
16:25 dumbass-afk yeas, seen them on ebay and at Fastenal
16:26 rue_shop2 http://www.teamassociated.com/parts/hardware/clips/
16:26 rue_shop2 oh my
16:26 rue_shop2 oh, they just spec by inside size
16:27 dumbass-afk you cannot put much load on them
16:28 dumbass-afk in my expereince, the more they are removed and put back on, the weaker they get
16:29 rue_shop2 most of the ones I have, were only put on and off once
16:29 rue_shop2 C clips are also called retaining rings
16:30 rue_shop2 so I'd have to use a drilll bit set to work out what the sizes of all these are
16:31 rue_shop2 black finish is called phosphate
16:32 mbass-afk
16:49 rue_shop2 I wonder what kinda phosphate
17:10 dumbass-afk it's an acid, it converts normal rust to a oxide that acts like anodising does for aluminum, you can buy it in various size buckets online
17:11 dumbass-afk look up phosphatizing
17:11 dumbass-afk or Parkerising
17:12 dumbass-afk http://en.wikipedia.org/wiki/Parkerizing
17:13 dumbass-afk there's spray-on, wash-off recipies you can get on ebay, etc
17:14 dumbass-afk i seem to recall decades ago people would phosphateise with Cokeacola
17:28 rue_house huh
17:31 dumbass-afk i have all this info in my head, and yet you believe i have no judgement
17:31 dumbass-afk huh
17:32 rue_shop2 remind me what I said to make you belive that?
17:32 rue_shop2 I think you get offended when Iget advise for a project but its in a different direction than I want to go so I dont take it
17:32 dumbass-afk "you sure you cannotmake a rocket heater?"
17:33 rue_shop2 I didn't know you didn't really need a heater
17:33 dumbass-afk the issue isn't me saying i cannot make a rocket heater, or any other wood burner, but i have no chmney to carry the smoke outside
17:33 dumbass-afk and you said i was freezing my ass off, as if i couldn't plug in an electric heater
17:34 rue_shop2 soemtiems when 'cant do' comes up against ' have to', compromises are found
17:34 dumbass-afk it just shows, no matter what i say, my words are useless
17:34 dumbass-afk who said anything about "cant do" ?
17:35 rue_shop2 you can well imagine how many interpertations there are of "I saw a green car drive down the street"
17:35 dumbass-afk no, tell me plainly
17:35 rue_shop2 how about I play "honky tonkin" again, instead
17:36 dumbass-afk then i still believe my words are nothing to you
17:37 rue_shop2 honestly, language is so crude I'm amazed anything at all can be conveyed
17:38 dumbass-afk you refuse to tell me plainly
17:41 dumbass-afk hell rue, i have not made any pcb at all since i used red string to make a coupling between shafts, i was not aware red string was such a signal that i deserved harassment, i used it only because i had it
17:41 dumbass-afk it's like having a garden means i deserve to be attacked by dogs
17:41 dumbass-afk or, as my mom plainly said, making my own electricity means i deserved to be disassembled by dogs
17:42 dumbass-afk i have no clue what humans want of me, except it always ends badly for me
17:42 dumbass-afk even mentioning it's cold in winter
17:42 dumbass-afk shit
19:03 Guest79275 hay dan
19:36 rue_house ?
21:57 rue_shop2 I think I can put 30V across a TL071 without it blowing up
21:57 rue_shop2 +-18V
21:57 rue_shop2 from ground
21:57 rue_shop2 which I think is 36V
21:57 Tom_itx who was zim?
21:58 rue_shop2 Invader Zim?
21:58 Tom_itx * zim has joined #garfield
21:58 Tom_itx * zim is now known as Guest79275
21:58 rue_shop2 dunno
21:58 Tom_itx since you ignore those
21:58 Tom_itx apparently knew you
21:59 rue_shop2 I came up with a great right side current sense
21:59 rue_shop2 I'm all excited
22:01 rue_shop2 still not sure how to make this settable votlage/current regulator
22:01 rue_shop2 I think I have to start with one or the other, and modify in the other feature
22:01 rue_shop2 my head just cant grasp the two at the same time
22:02 rue_shop2 always like digital circuits
22:02 rue_shop2 ^d
22:02 rue_shop2 this analog stuff is pickey and never works like the math says it will
22:03 Tom_itx iirc i had an old ACE brand voltage current supply
22:04 Tom_itx ACE made model airplane electronics way way back
22:04 rue_shop2 damn, somewhere I made a diagram of my micronta
22:04 rue_shop2 I wonder if I put it under the suppy
22:05 rue_shop2 sweeeet I rock! so predictable!
22:29 rue_shop2 ok I understand the design, but its making my head hurt
22:31 dumbass-afk too bad you don't havea local dumbass you could discuss it with
22:49 rue_shop2 its a strange setup cause they put the LM723 grounded on the + rail of the output,
22:50 rue_shop2 which is operated by common collector NPN from the outputs seperate supply
22:50 rue_shop2 so all the references inflict pain to the brain
22:51 rue_shop2 my high side current sense wont work, it needs lots of headroom
22:51 rue_shop2 which is dos't have
22:53 Tom_itx i'm growing weary of irc i'm afraid
22:53 rue_shop2 its been pretyt quiet latley
22:54 Tom_itx maybe it's just life i'm growing weary of
22:54 rue_shop2 Tom_itx, your not working on as many of your projects latley either it seems
22:54 rue_shop2 suddenly I have all these people around here
22:54 rue_shop2 there is a local maker thing comming togethor
22:56 rue_shop2 hmm
22:56 Tom_itx still doing your class?
22:56 rue_shop2 staying on the positive rail, how DOES one sense current thru 0 to 30V
22:56 rue_shop2 yup
22:57 rue_shop2 I think I have to use one of the isolated sense devices
22:57 rue_shop2 they are frustrating, they 0 at 2.5V
22:59 rue_shop2 recon I just have to tough it out
22:59 rue_shop2 Tom_itx, whats the last new project you took on?
22:59 Tom_itx i have no idea
22:59 Tom_itx it's been quite a while
22:59 rue_shop2 your temp logger?
23:00 rue_shop2 Tom_itx, the comming of spring will prolly help
23:00 Tom_itx i made a new cover for my pendant. i suppose that was the last thing: http://tom-itx.dyndns.org:81/~webpage/cnc/pendant/pendant2.jpg
23:01 rue_shop2 nive
23:01 Tom_itx but that seems like ages ago
23:01 rue_shop2 nice even
23:01 Tom_itx finally got the proper engraving bits
23:01 rue_shop2 winter is long and depressing, dont get too dismayed by it
23:01 Tom_itx life is long and depressing
23:01 rue_shop2 I'm waiting for spring to get the energy to think about building a new house
23:02 rue_shop2 what did you use for colouring in the engraving?
23:02 Tom_itx black spray paint
23:02 Tom_itx then just wiped it off
23:03 rue_shop2 rubbed off wet of polished off after dry?
23:03 Tom_itx dipped a toothpick in it and dobbed it in the cuts
23:03 Tom_itx then wiped it off
23:04 rue_shop2 silk screening, there are a few things that I want to make, but setting up to make just one is kinda impractical
23:04 rue_shop2 realized that about a few circuits I'v just made up on veroboard
23:14 rue_shop2 want to help me set up a difference amp with a gain of 5.41 and an offset of 2.5V?
23:15 rue_shop2 always messes me up
23:35 rue_shop2 what has a descent DAC I can strip out
23:35 rue_shop2 cdroms seem to use something stupid
23:52 dumbass-afk i am just real tired of never doing anything right
23:53 dumbass-afk it's always something new too, i cannot get usps mail, i cannot even keep warm right