#garfield Logs

Dec 27 2020

12:06 PM polprog: https://www.youtube.com/watch?v=0ywbd76wVtk
03:52 PM polprog: https://allegrolokalnie.pl/oferta/generator-funkcyjny-voltcraft-fg-506-6mhz
03:52 PM polprog: bought a siggen
03:54 PM polprog: http://www.powertronics.com.br/fotos/18072011_6362.pdf
03:55 PM polprog: :o it has a counter
04:01 PM rue_mohr: :)
04:02 PM rue_mohr: ooo what functions does it do?
04:03 PM rue_mohr: ah there
04:03 PM rue_mohr: ok,
04:04 PM rue_mohr: the old ones I used went to 1Mhz, and it was an AWEFULL 1Mhz, if I wanted to use it, I had to do a lot of post-processing
04:05 PM rue_mohr: the new one I made goes from .1Hz to 10Mhz
04:05 PM rue_mohr: the 10M needs a termination resistor
04:05 PM rue_mohr: and its just a freq gen, no duty or voltage control, ttl 50% only
04:06 PM rue_mohr: I havn't used it much since I got the chniese function gen
04:09 PM rue_mohr: it must be a synth output
05:40 PM polprog: woah
05:40 PM polprog: i got it i got it
05:40 PM rue_mohr: ?
05:40 PM polprog: adjustable negative voltage converter
05:41 PM polprog: with closed loop control
05:41 PM rue_mohr: hah
05:41 PM rue_mohr: well lets see!
05:42 PM polprog: -3.8 V min
05:42 PM polprog: lrt mr draw it
05:42 PM polprog: let me draw it*
05:51 PM rue_mohr: did I tell you guys I got some help and the cnc is on the deck?
05:58 PM polprog: no
06:05 PM polprog: https://polprog.net/rozne1/ircjunk/dcdc/negative_dcdc.jpg
06:05 PM polprog: https://polprog.net/rozne1/ircjunk/dcdc/negative_dcdctrace.png
06:05 PM polprog: ch2 is the uln drive
06:06 PM polprog: this core can do -3.8V at best
06:06 PM polprog: thats at full drive
06:06 PM polprog: fun fact, if you disable the drive co,pletely the feedback divider charges it up to +5V, heh
06:15 PM polprog: aah the diode is flipper oops
06:15 PM polprog: flipped
06:16 PM polprog: this core sucks
06:16 PM polprog: i need to wind a proper one
06:18 PM polprog: woah, phone line isolator gives me -5v easily
06:36 PM rue_shop1: oh right
06:38 PM rue_shop1: ornice
06:38 PM rue_shop1: polprog, nice
06:38 PM rue_shop1: polprog, let me draft you up soemthing to try
06:39 PM rue_shop1: It'll do +5 -> -5
06:42 PM polprog: it is pretty late though :<
06:42 PM polprog: weird, my cheek ithches
06:42 PM polprog: is itching
06:45 PM rue_mohr: do you have a small pnp?
06:45 PM polprog: i do
06:46 PM polprog: ill try it tomorrow though
06:46 PM rue_mohr: sure
06:46 PM polprog: i should goto sleep
06:58 PM rue_shop1: ARRR SHE WHISTLES LIKE A BANSEE!
06:58 PM rue_shop1: ARRR SHE WHISTLES LIKE A BANSHEE!
06:58 PM rue_shop1: ..
06:58 PM rue_shop1: and this isn't regulated, normally, I would adjust the turns to compensate for the diode loss
07:03 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1180346.jpg
07:04 PM rue_mohr: its not regulated, its locked to the turns ratio
07:04 PM rue_mohr: so you get 4.3V if your diode drops .7
07:04 PM rue_mohr: mine ran at 11kHz, "squeals like a banshee"
07:05 PM rue_mohr: the diode to +5 constrains the switching duty to ~50%
07:10 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/p1180345.jpg
07:10 PM rue_mohr: forgot that one
07:26 PM polprog: self resonating hmm
07:30 PM Tom_L: who's whistling now?
07:33 PM polprog: hmm, ill test that tomorrow
07:33 PM polprog: the converter is whishling. it's an osha requirement
07:34 PM polprog: the operator must know there is dangerous -5V on the output
07:40 PM Tom_L: ahh
07:41 PM polprog: nighters
07:41 PM Tom_L: ya ya that's what you said last night too
07:42 PM polprog: surprise
07:42 PM polprog: one of these days ill go to sleep at 9 pm and you will wonder where did he go
07:42 PM polprog: :P
07:43 PM Tom_L: rue is +2 from me but i dunno about you
07:44 PM * darkrose is on UTC+10, but mostly lives a 24.5 hour day, so sleep time changes regularly
07:44 PM Tom_L: 2:32 am?
07:44 PM Tom_L: yeah you're an aussie right?
07:45 PM darkrose: yeah
07:45 PM Tom_L: what part?
07:45 PM darkrose: brisbane queensland
07:45 PM Tom_L: we knew a guy from gold coast
07:45 PM Tom_L: and brisbane iirc
07:45 PM Tom_L: i forgot where thebear was from
07:47 PM Tom_L: some gal i forget her handle was in sydney
07:47 PM Tom_L: rue might remember
08:42 PM rue_shop1: hmm
08:42 PM rue_shop1: something about a fountian
08:43 PM rue_shop1: I cant recall the nick
08:43 PM rue_shop1: she was making fountians?
08:47 PM Tom_L: she had an electric scooter too
08:59 PM Tom_L: rebecca
08:59 PM rue_mohr: yea
09:03 PM Tom_L: done with that class?
09:13 PM rue_mohr: yea waiting for government marks
09:15 PM Tom_L: gonna start work on the big cnc again now?
09:30 PM rue_mohr: yea I'm trying to finish my bench power supply
09:31 PM rue_mohr: it took me 2 days to do up the regulator board
09:31 PM Tom_L: i thought that one was coming to an end
09:31 PM rue_mohr: I just finished basic tests, and its basically working, I may have to fight with some oscillation issues
09:31 PM rue_mohr: it just needs that last board
09:31 PM rue_mohr: machined dip16
09:33 PM Tom_L: work is slowing down here
09:33 PM rue_mohr: wasn't it already slow?
09:34 PM Tom_L: yeah slower than normal
09:34 PM Tom_L: nothing tomorrow
09:34 PM Tom_L: some of that is because it's between christmas and newyears
09:35 PM rue_mohr: on tuesday were redoing a counter at a building supplies store
09:35 PM Tom_L: first scheduled is wed
09:35 PM Tom_L: unless something changes
10:39 PM rue_mohr: hmm, I wonder how much work that power supply will take to finish up
10:40 PM rue_mohr: somewhere I have a start on motor drivers for the cnc
10:40 PM Tom_L: gotta fine me another project soon..
10:40 PM rue_mohr: how about a single pass on the chuck adatper?
10:40 PM Tom_L: yeah maybe
10:41 PM rue_mohr: all from the top
10:41 PM rue_mohr: threaded hole for a stub to hold the chuck
10:41 PM Tom_L: dunno if i have a 3/8 fine thread bold..
10:41 PM Tom_L: bolt
10:41 PM rue_mohr: side of the street, they fall off cars all the time
10:42 PM Tom_L: i may have one
10:42 PM rue_mohr: yea get it from that
10:42 PM rue_mohr: its probably not holding on anything usefull anyhow
10:42 PM Tom_L: at least the thread numbers are proven
10:43 PM rue_mohr: yep
10:45 PM Tom_L: i think brass should be ok for that maybe
10:45 PM Tom_L: i could do steel but i've got the brass too
11:17 PM rue_mohr: I'd go with the brass
11:17 PM rue_mohr: less chance of a tool inncedent
11:18 PM Tom_L: i'm not worried about that, the steel cuts fine too
11:51 PM Tom_L: ok, all programmed
11:59 PM Tom_L: 22 min spindle time