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[20:59:43] <Tom_itx> bat files are rather powerful if you can decipher them
[21:00:16] <rue_shop4> yep
[21:00:23] <Tom_itx> rue_1, rue_2, rue_3 whasssup tonight?
[21:00:32] <rue_shop4> negitive resistance
[21:00:41] <Tom_itx> i'm trying to automate processes for idiots
[21:00:55] <rue_shop4> one of the lackies used a pn2222 as the active element in a relaxation oscillator
[21:01:09] <rue_shop4> I made a curve tracer "" and started going thru my transistors
[21:01:24] <rue_shop4> turns out pn2222 (2n2222) is one of the only ones that has negitive resistance
[21:01:30] <rue_shop4> one of, BUT
[21:01:39] <rue_shop4> 2n5551 has MUCH MORE
[21:02:07] <rue_shop4> and they are SUPER cheap from aliexpress, I just bought 500 for $10
[21:02:16] <Tom_itx> i'm getting quite close with my program
[21:02:24] <rue_shop4> ok
[21:02:32] <Tom_itx> fix a few reports and should be ~fair
[21:02:45] <rue_shop4> you gonna take it to market?
[21:02:50] <Tom_itx> no
[21:03:00] <Tom_itx> writing it for a friend starting a business
[21:03:48] <Tom_itx> remembering dos is somewhat fun
[21:05:11] <Tom_itx> but i'm trying to use best of both worlds by exporting files and dual booting to windows to manage the data for reports or mailouts etc
[21:05:59] <Tom_itx> it would have taken me forever to write it in windows
[21:06:38] <Tom_itx> using .com file trickery too
[21:06:52] <Tom_itx> to use the keyboard buffer to execute commands in other programs
[21:07:05] <Tom_itx> to auto import the data
[21:48:58] <rue_shop4> ooooo!! 2sc945 is even better!
[21:58:13] <katsmeow> mou
[22:27:30] <rue_house> kat!
[22:27:49] <rue_house> 2sc945 seems to be the best performer yet on the negitive resistance thing
[22:28:03] <rue_house> mpsA42 will do it, mpsA06
[22:28:13] <rue_house> 2n5550 and 2n5551
[22:28:31] <katsmeow> ok
[22:28:41] <rue_house> I'v got a vco assembled that goes from 300hz to 34Khz
[22:28:45] <rue_house> :)
[22:29:01] <rue_house> 2 decades is pretty good
[22:29:04] <katsmeow> pretty wide range
[22:29:36] <rue_house> the ramp could be used for pwm generation
[22:30:03] <katsmeow> what you can do is merge decades with a PLL , you cannot sweep fat thru the PLL range, but you cold manually tune seaml;essly thru the range
[22:30:48] <rue_house> yea, I'm trying to scare up a pll idea
[22:31:58] <rue_house> put togethor a curve tracer on the scope and went thru all sorts of parts
[22:32:13] <rue_house> I found out nothing in the diac drawr is a diac :)
[22:32:35] <rue_house> lots of them were stripeless resistors
[22:33:10] <katsmeow> heh
[22:33:12] <rue_house> I thought some of the ir leds might exibit negitive resistance on reverse breakdown
[22:33:28] <rue_house> but none of them would break down under the 25V I had available
[22:33:55] * katsmeow hands rue an ignition coil
[22:34:20] <rue_house> if its not gonna break down under 12V, its not exciting
[22:34:43] <katsmeow> 6v lamp
[22:34:56] <rue_house> :)
[22:35:04] <rue_house> it dosn't double back tho does it?
[22:35:19] <katsmeow> double back?
[22:35:36] <rue_house> negitive resistance curve
[22:35:53] <rue_house> sloped \ instead of /
[22:35:58] <katsmeow> as the V across it drops, the resistance drops too
[22:36:01] <rue_house> for --> V
[22:36:06] <rue_house> ^I
[22:36:58] <rue_house> I know of it for AGC, esp in sin osc's
[22:37:55] <katsmeow> umm, ok
[22:38:01] <rue_house> I been trying to wrap my brain around negitive resistance amps for bidirectional apps like telephones
[22:38:21] <katsmeow> i have other things to wrap my brain around
[22:38:35] <rue_house> where the negitive resistance is used to compensate for line resistance
[22:38:39] <katsmeow> good thing you exist to handle those things i don't
[22:38:42] <katsmeow> and vice versa
[22:39:39] <rue_house> I'v wrestled with relaxation oscillators for a long time "becasue I could't get the parts to make one'
[22:39:50] <rue_house> all this time I'v had pn2222 }:|
[22:40:06] <rue_house> and C945, its the most popular transistor in old vcrs
[22:41:48] <rue_house> I'm cursious how large the region needs to be to make something like an RF osc using one
[22:42:01] <rue_house> tunnel diodes are almost all negitive resistance
[22:42:33] * katsmeow has never looked into it, the parts useto be WAY too pricey
[22:42:42] <rue_house> pn2222
[22:42:43] <katsmeow> except for the lamps and NE2
[22:42:45] <rue_house> 2sc945
[22:42:54] <rue_house> its been there the whole time
[22:43:05] <katsmeow> in the 1970's they weren't cheap
[22:43:12] <rue_house> WHAT you do, it leave the base unconnected, and reverse the CE
[22:43:16] <katsmeow> transistors useto cost more than vac tube
[22:43:18] <rue_house> go figure
[22:43:42] <rue_house> the reverse CE has a negitive resistance region
[22:43:53] <rue_house> indeed, but ...
[22:45:19] <rue_house> the pn2222 datasheet dosn't actually talk about the reverse CE breakdown
[22:46:21] <katsmeow> prolly doesn't discuss using it as a pnp transistor either
[22:46:26] <rue_house> I'm still feeling rather [8-o about this
[22:46:32] <rue_house> !?
[22:46:39] <rue_house> please tell
[22:47:54] <katsmeow> operated under the reverse Vce, some transistors will operate as the otehr polarity, but with much lower gain
[22:48:23] <rue_house> ooo
[22:48:31] <katsmeow> at 7v-20v-40v or so, they hit breakdown and avalanch , or smoke, if you give them enough current
[22:48:47] <rue_house> that would comfuse someone trying to reverse engineer a circuit to all hell
[22:51:34] <katsmeow> i first ran across one in a radioshack schematic of a mute function on a tape deck, they were feeding AC to a transistor collector, and it worked anyhow
[22:52:19] <rue_house> huh
[22:54:01] <katsmeow> http://mega65.org/
[22:54:51] <rue_house> I wonder why they didn't use SD instead of floppy
[22:55:52] <katsmeow> the oem C64 floppies were external, and who uses floppies anymore?
[22:55:55] <rue_house> why didn't they just recode the name on the rom instead of mauling the images?
[22:56:10] <katsmeow> they prolly hasve ram drive ports all over the thing somewhere
[22:56:15] <rue_house> yea I just upgraded my mowerbot, it uses CF now
[22:56:48] <rue_house> all they had to do was change the strings in the rom, huh
[22:57:31] <rue_house> ok, know any outside the box ways to make a toggle ff?
[22:58:13] <katsmeow> the olde way: two transistors , caps, and a few resistors
[22:58:41] <katsmeow> could also do a voltage multiplier that resets when the target voltage is reached
[22:59:13] <rue_house> oh a resetting step gen
[22:59:15] <rue_house> hey
[22:59:34] <rue_house> if the charge time was limited
[22:59:37] * rue_house thinks
[23:00:05] <rue_house> the relaxation could reset it
[23:00:20] <rue_house> set it up so two pulses take it just over
[23:00:27] <katsmeow> yeas
[23:00:35] <rue_house> er, no, thats not gonna hold it low
[23:00:39] <katsmeow> or a zener
[23:00:50] <rue_house> hmm
[23:01:05] <rue_house> I know the symetric transistor way
[23:01:30] <rue_house> wait, there is a /2 with neon that
[23:01:42] <rue_house> is just relaxation based ring counters
[23:03:18] <rue_house> if it can be done with neon, it can be done with this 2222 trick
[23:03:24] <rue_house> (at a lower voltage)
[23:19:02] <katsmeow> http://www.ebay.com/itm/Ultra-rare-Commodore-65-C65-DX64-prototype-working-serial-22-/171673209321
[23:26:39] <katsmeow> quote// Programming is the eternal competition between programmers who try to make apps more and more idiot proof and the universe that makes dumber idiots. So far, the universe is winning...