--- Day changed Sun Sep 27 2009 | ||
genehacker | hmmmm.... | 00:00 |
---|---|---|
genehacker | hey I think that andy howell guy was at dorkbot | 00:03 |
ybit | are you guys going for a toolbook-like animation with pycal3d? | 00:07 |
kanzure | ybit: toolbook incorporated that idea from skdb | 00:08 |
drazak | man sometimes you guys are more boring than reading the most bland technical manual | 00:08 |
fenn | what about an auto-generated technical manual | 00:09 |
kanzure | you do realize we're basically making a bland technical manual generator? | 00:09 |
kanzure | hey >:( | 00:09 |
kanzure | stop reading my brains | 00:09 |
fenn | sorry it's so difficult with all the cross talk in here | 00:09 |
kanzure | didn't yo mamma tell you to not cross the signals? | 00:09 |
fenn | can't stop the signal mel | 00:10 |
genehacker | complete with indecipherable japanese and oh wait... | 00:10 |
drazak | man sometimes you guys are more boring than reading the most bland technical manual | 00:10 |
drazak | shit | 00:10 |
drazak | I just said that | 00:10 |
drazak | nevermind | 00:10 |
drazak | I was scrolled up like 2 lines | 00:11 |
drazak | and thought it didn't post :S | 00:11 |
kanzure | fail | 00:11 |
genehacker | isn't there some version of autocad that does that? | 00:11 |
genehacker | i think that's patented code | 00:11 |
kanzure | http://media.photobucket.com/image/signals%20cross%204chan/Ragnor144/Fail%20Macros/GiraffeeFail.jpg | 00:11 |
fenn | oh noes patented code | 00:11 |
fenn | the sovereign nation of AutoCAD | 00:11 |
fenn | they are going to bust down my door with military robots | 00:12 |
genehacker | no | 00:12 |
genehacker | they're just going to sue you or something | 00:12 |
genehacker | woohoo fun winblows error time | 00:13 |
genehacker | now what does one use to bore out large diameter holes in aluminum rod stock? | 00:15 |
fenn | why not just buy the stock as tubing instead | 00:16 |
genehacker | can you buy cheap 1.5 foot lengths of 2 inch OD aluminum tubing for not expensive? | 00:17 |
genehacker | I need to check the machine shop... | 00:19 |
genehacker | I want to make a high power piston based water gun from hell | 00:19 |
fenn | just use a pneumatic cylinder | 00:21 |
genehacker | now where do I get those? | 00:21 |
genehacker | here's the deal | 00:22 |
genehacker | I want a dual diameter piston | 00:24 |
fenn | a telescoping piston? | 00:24 |
fenn | oh you could use a bike pump | 00:24 |
genehacker | hmmm.. on second thought I don't have an aircompressor | 00:25 |
genehacker | this might be impractical | 00:25 |
fenn | eh? | 00:25 |
fenn | mind sharing with the rest of the class? | 00:26 |
genehacker | http://www.sscentral.org/homemade/supercannon2.html | 00:27 |
genehacker | I was thinking something like this | 00:28 |
genehacker | but with a piston that has a large diameter that goes to a small diameter | 00:29 |
fenn | a tapered bore? | 00:29 |
genehacker | small diameter piston goes to a small diameter pipe filled with water connected to the nozzle | 00:31 |
genehacker | other end connects to pressurized air pipe | 00:31 |
fenn | oh, an intensifier | 00:31 |
genehacker | yeah | 00:31 |
fenn | don't kill yourself | 00:32 |
genehacker | well considering I'm not a very good machinist, I don't have much in the way of tools or transportation | 00:33 |
genehacker | it's probably not going to happen | 00:33 |
fenn | you can get air-powered hydraulic pumps from harbor freight | 00:33 |
fenn | also they sell a little air powered grease gun for $20 | 00:33 |
genehacker | hmmm... | 00:34 |
fenn | but realistically 100psi is way too high for a squirt gun anyway | 00:34 |
genehacker | I want to spend less than $25 | 00:34 |
fenn | hah | 00:34 |
fenn | buy a squirt gun | 00:34 |
genehacker | i did | 00:34 |
genehacker | this is for an assassin contest | 00:34 |
fenn | i don't know what that means | 00:34 |
genehacker | it means that people with waterguns are going to be a common sight in ETC | 00:35 |
* ybit eats CIA-32 | 00:47 | |
* CIA-32 tastes crunchy | 00:47 | |
ybit | see, drazak, we're not boring | 00:47 |
* ybit rubs CIA-32's tummy | 00:48 | |
CIA-32 | *purr* | 00:48 |
genehacker | hey don't abuse our bots | 00:49 |
drazak | lol | 00:49 |
ybit | genehacker: i think cia-32 doesn't like to be referred to as 'bot', it's slightly derogatory | 00:50 |
genehacker | they might have something that resembles the feelings of a flatworm! | 00:50 |
* ybit thinks the pythonocc svn is going to build, not the one in kanzure's dir | 00:50 | |
genehacker | I wonder if sufficiently fast programs would have something like senses | 00:52 |
ybit | gn i suppose :-\ | 00:52 |
* ybit kills CIA-32 | 00:52 | |
* CIA-32 dies | 00:52 | |
genehacker | would they feel pain? | 00:53 |
ybit | yeah | 00:53 |
* ybit kicks CIA-32 | 00:53 | |
CIA-32 | ow | 00:53 |
ybit | see | 00:53 |
genehacker | though what is pain | 00:53 |
* ybit suggests changing the topic to philosophy allowed between the hours of 2-5am | 00:54 | |
genehacker | philosophy detected terminating | 00:54 |
ybit | so come back in an hour, and you might be in the clear | 00:55 |
* ybit waves gn | 00:55 | |
genehacker | I should just keep mapping out the reactions | 00:55 |
* ybit hugs CIA-32 | 00:56 | |
* CIA-32 hugs ybit | 00:56 | |
genehacker | sleep is for weak people | 00:56 |
ybit | i'll remember that and call you when you drift off later this afternoon | 00:57 |
ybit | ..just to remind you | 00:57 |
ybit | third time's a charm: and i'm out | 00:57 |
genehacker | ok | 00:59 |
drazak | blah | 01:15 |
drazak | been staring at circuit diagrams all day | 01:15 |
drazak | and excel | 01:15 |
drazak | trying to part out this freaking amp | 01:15 |
genehacker | ugh | 01:22 |
genehacker | what does 3 h stand for with reference to chemical abbreviations | 01:23 |
genehacker | as far as I know combining two chemicals that don't contain phosphorus to make something with phosphorous is impossible | 01:25 |
genehacker | phosphine | 01:29 |
genehacker | it's gotta be phosphine | 01:29 |
drazak | what context | 01:31 |
genehacker | in synthesizing beta-cyanoethyl N,Nbis(diisopropylamino)chlorophosphine | 01:32 |
genehacker | from | 01:33 |
drazak | where does 3h come from? | 01:33 |
genehacker | i-Pr2EtN, 3 h, CH2-Cl2, 0 °C --> RT, 70-77% | 01:33 |
genehacker | it's gotta be phosphine | 01:33 |
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bkero | Anybody try doing some OCR recently? | 04:54 |
bkero | kanzure: ? | 04:54 |
fenn | why d0 you ask? | 05:19 |
kanzure | no not recently | 07:16 |
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ybit | was nalioth informing about cloaks for this channel? | 11:53 |
ybit | o i c, group registration | 12:00 |
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* ybit is looking for modular house designs | 15:24 | |
ybit | will gradually expand the building as my limited income allows | 15:25 |
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kanzure | houses are for quitters | 15:27 |
ybit | yeah, modular warehouse, how 'bout that? | 15:30 |
Utopiah | yep, cf http://www.peopleofwalmart.com/?p=3914 | 15:31 |
kanzure | shipping containers | 15:31 |
ybit | hah, i like the second comment fromt that link | 15:33 |
kanzure | i made a wrapper for cal3d | 15:33 |
kanzure | http://adl.serveftp.org/~bryan/pycal3d/ | 15:33 |
ybit | nice, and you included install notes | 15:36 |
ybit | http://www.containercity.com/riverside-building.html nice | 15:38 |
ybit | seeing some really neat designs using shipping containers, if the price is reasonable, i'm sold | 15:39 |
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ybit | ~$100 each, but it seems you have to buy in bulk | 15:40 |
ybit | e.g. http://cgi.ebay.com/20%60-shipping-cargo-storage-container-So.-California_W0QQitemZ140224168109QQcmdZViewItem | 15:41 |
genehacker | ybit are you plannin on making snowcrash style apartment | 15:43 |
genehacker | s | 15:43 |
ybit | more like a warehouse, no apartments | 15:46 |
genehacker | have you read snowcrash? | 15:51 |
ybit | though, if the hackerspace idea comes into fruitition, i don't have a problem with friends living there, it certainly wouldn't be much of a technical problem adding on another container | 15:51 |
ybit | no | 15:51 |
genehacker | read snowcrash | 15:52 |
genehacker | it's good | 15:52 |
ybit | genehacker: hows about you describe these apartments to me :) | 15:53 |
genehacker | http://www.technovelgy.com/ct/content.asp?Bnum=121 | 15:56 |
AchiestDragon | ybit the shiping containers are sell at about £800 gbp on ebay , although the conversions cost upwards of £3000 depending what you want inside it | 15:58 |
ybit | genehacker: thanks for the link | 15:58 |
drazak | ybit: call around to railroads and shippers and stuff and see if htey have extra ones that they want to get rid of | 16:09 |
nykodemus | I both second and third the suggestion to read snowcrash | 16:26 |
ybit | nykodemus: that is not allowed my friend, second or third, but not both :P | 16:44 |
kanzure | http://adl.serveftp.org/~bryan/screenshots/2009-09-27-porrasturvat.png | 17:01 |
genehacker | kanzure why are you playing stair dismount? | 17:08 |
kanzure | i feel compelled to try to decompile anything that people don't offer sources to | 17:08 |
genehacker | are you going to use a search algorithm to find the highest possible score? | 17:09 |
kanzure | no the source isn't available | 17:10 |
genehacker | I have something that doesn't have the source | 17:10 |
genehacker | that is the only reason I don't use linux | 17:10 |
genehacker | my textbook reader | 17:11 |
kanzure | does it run under wine? | 17:12 |
genehacker | no | 17:13 |
genehacker | it needs .NET framework 3.5 | 17:13 |
genehacker | and of course that won't work | 17:13 |
kanzure | oh then mono should be able to run it | 17:14 |
genehacker | what's mono? | 17:15 |
kanzure | sudo apt-get install mono | 17:15 |
kanzure | it runs .NET on linux | 17:15 |
genehacker | really? | 17:15 |
genehacker | ok | 17:15 |
genehacker | I'll try that when I boot up linux | 17:16 |
genehacker | if you feel compelled to decompile everything | 17:17 |
genehacker | I've got a whole bunch of fun stuff for you to decompile | 17:17 |
ybit | the cost is roughly 1.5kusd-2k like AchiestDragon mentioned | 17:41 |
ybit | but as a npo, i'm guessing these companies would sell at a reduced cost and take the tax write-off | 17:44 |
kanzure | i need a marketing drone | 17:46 |
kanzure | anybody in here into marketing? | 17:46 |
* ybit quits blogging about building construction materials, though there are several ones which can be implemented cheaply: tire home, mud home, wood (from the mini forest that will be chopped down) | 17:50 | |
ybit | kanzure: what are you looking to market? | 17:50 |
kanzure | me | 17:52 |
genehacker | that can be interpretted in many ways | 17:53 |
genehacker | step 1 of marketing, who do you want to sell to? | 17:54 |
genehacker | what your selling doesn't matter | 17:54 |
genehacker | with good marketing it can be sold | 17:54 |
genehacker | that's all you need to know | 17:55 |
fenn | ybit get one of these http://www.farmtek.com/farm/supplies/cat1;ft1_tension_fabric_buildings;ft1_clearspan_tension_fabric_structures.html | 19:05 |
ybit | that's neat | 19:06 |
ybit | guess the articles of incorporation need to filed soon before i start hitting up companies | 19:06 |
ybit | fenn: my question is how does it withstand highspeed winds during tornado season. | 19:16 |
ybit | how +well | 19:16 |
fenn | um. how well does anything withstand tornadoes? | 19:17 |
fenn | seems to me that the rounded ones would probably be the most robust structure in a wind storm | 19:18 |
fenn | you can also get a "wide" building which is shorter | 19:21 |
fenn | http://www.clearspan.com/fabric/structures/ext;Structures/Sizes.html | 19:24 |
fenn | http://en.wikipedia.org/wiki/Salt_Lake_Tabernacle#Construction | 19:30 |
fenn | you can get custom printed graphics | 19:39 |
genehacker | in color? | 19:40 |
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fenn | you can get any color you want as long as it's blue | 19:46 |
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kanzure | nice email from anders | 20:40 |
kanzure | good to see he's not totally dead | 20:40 |
drazak | does anyone know of any unity gain stable opamps that have low voltage requirements and are suitable for an audio amp in the ground position? | 20:42 |
genehacker | no, but I know of some fluidic sound amplification devices with good frequency response qualities | 20:43 |
drazak | I already have a design, I just need to pick an opamp | 20:43 |
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kanzure | hello mason-l | 20:55 |
mason-l | Hello kanzure | 20:55 |
kanzure | huh docstrings are an optional parameter for swigging stuff. /me fixes | 20:57 |
kanzure | %feature("autodoc", "1") | 20:57 |
genehacker | http://hardware.slashdot.org/story/09/09/27/2020204/Revisiting-DIY-HERF-Guns?art_pos=4 | 20:57 |
genehacker | I wonder if HERF guns will become more widespread if EEstor sells their capacitors to the public | 20:58 |
katsmeow-afk | TL081 or TL071 | 20:59 |
katsmeow-afk | but you didn't define "low voltage" , so i dunno | 21:00 |
kanzure | in what package is gl/gl.h given? apt-file search isn't showing me anything | 21:58 |
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kanzure | hello idiot | 22:02 |
Guest91727 | hello kanzure | 22:11 |
drazak | katsmeow-afk: TL071 sucks for audio | 22:19 |
drazak | katsmeow-afk: sure, the slew rate is fast enough, and it's like what, 30khz? it just doesn't sound good | 22:19 |
katsmeow-afk | where do you get the 30khz figure? | 22:23 |
katsmeow-afk | you want rail-to-rail +/- 15v ? | 22:23 |
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katsmeow-afk | besides, you know you can put a simple gain stage after it? | 22:24 |
fenn | perhaps i'm an anti snob, but isn't just about any transistor more than fast enough for audio? | 22:27 |
katsmeow-afk | yeas, but few are linear all over their curve,, and a curve is by definition not linear | 22:28 |
katsmeow-afk | however, a decent opamp and any ole transistor is easily good enough for PA use | 22:28 |
drazak | katsmeow-afk: way lower than 15v, try 7.6v rail to rail, my audio opamp is a dual channel AD823, but they don't make a single channel version for my ground channel | 22:41 |
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katsmeow-afk | yeas, low voltage operation can be a pita, due to limited output swings and lockups | 22:42 |
drazak | yeah | 22:42 |
drazak | it's for a NiMH 9volt battery powered headphone amp | 22:43 |
katsmeow-afk | can you level shift your signal up and make a fake gnd at 3.8v? | 22:43 |
drazak | here, look at the schematic | 22:44 |
drazak | http://tangentsoft.net/audio/pimeta2/misc/sch-2.01.pdf | 22:44 |
katsmeow-afk | ? | 22:44 |
katsmeow-afk | umm, they call out al lthe parts numbers there for you | 22:45 |
katsmeow-afk | why ask us? | 22:45 |
drazak | because I'm not using all the same parts | 22:46 |
drazak | :P | 22:46 |
katsmeow-afk | IC2 already make a vcc/2 gnd for you | 22:46 |
drazak | right, the tle2426 | 22:47 |
katsmeow-afk | i guess i don't understand the problem | 22:47 |
katsmeow-afk | [22:42] <drazak> katsmeow-afk: way lower than 15v, try 7.6v rail to rail, my audio opamp is a dual channel AD823, but they don't make a single channel version for my ground channel | 22:47 |
drazak | right | 22:48 |
drazak | the ground channel takes a single channel opamp | 22:48 |
katsmeow-afk | what are you calling a "ground channel" ? | 22:48 |
katsmeow-afk | all those are using 2 opamps | 22:48 |
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katsmeow-afk | oh, the IC2 itslef?? | 22:49 |
drazak | no, OPAG | 22:49 |
katsmeow-afk | http://www.google.com/search?q=%22low+voltage%22+%22single+supply%22+opamp | 22:51 |
katsmeow-afk | i understand the point of an opamp there, but i suspect you can get by with C3 C4 C5 alone | 22:53 |
drazak | 3-channel topology keeps headphone return currents from disturbing the signal ground | 22:54 |
katsmeow-afk | yeas | 22:54 |
katsmeow-afk | ok, use a dual or quad package in place of OPALRG$1, OPALRG$2 , OPAG , and the TLE2426 | 22:55 |
katsmeow-afk | instead of what looks like 4 separate 8pin dips? | 22:56 |
drazak | it's 2 8 pin drops | 22:56 |
katsmeow-afk | IC2 is shown as 1/2 the chip, can't you use the other half for the OPAG circuit? | 22:56 |
drazak | the tle2426 comes in a to92 package | 22:56 |
drazak | and it's shown as 1/2 | 22:57 |
katsmeow-afk | the tle2426 has "1/2" written on it, praps it's a different pack | 22:57 |
katsmeow-afk | or is it "1 of 2" , not 1/2 ? | 22:57 |
drazak | hold on | 22:58 |
katsmeow-afk | either way, use another for the OPAG ? | 22:58 |
drazak | use another tle2426? | 22:58 |
katsmeow-afk | yeas, you don't actually need gain there | 22:58 |
drazak | does it have opamp action? | 22:59 |
drazak | I don't know a lot about the tle2426 | 22:59 |
katsmeow-afk | me either, but the OPAG - LMH6321 is all buffer, and vreference and current source/sink, not gain | 22:59 |
katsmeow-afk | it's headphones, it's hardly hifi | 23:00 |
drazak | uhm | 23:00 |
drazak | it's to drive my HD600's | 23:00 |
katsmeow-afk | ? | 23:00 |
drazak | hifi headphones | 23:01 |
katsmeow-afk | k | 23:01 |
katsmeow-afk | :-/ | 23:01 |
drazak | I'm hand matching resistors between left and right channel, etc | 23:01 |
drazak | it's not a crappy amp :P | 23:01 |
katsmeow-afk | oohhh | 23:01 |
katsmeow-afk | ok,, then, use another OPALRG , it's a dual-opamp in one pack? | 23:02 |
drazak | OPALR is a dual opamp, yeah, I don't know if the in/out pinouts are right to go in a dip socket for a single opamp | 23:02 |
drazak | I'll need to look at the datasheets | 23:03 |
katsmeow-afk | use one side for the OPAG, and a resistor string and the other side for the TLE24226 | 23:03 |
drazak | dude | 23:03 |
drazak | I'm buying the circuit board | 23:03 |
drazak | I'm deciding how to populate it | 23:03 |
katsmeow-afk | either way, if you are substituting parts around from what's said on irc, you're going to redo the pcb layout | 23:03 |
katsmeow-afk | you can't drop in a dual opamp pack where it calls for a single, no way | 23:04 |
drazak | http://tangentsoft.net/audio/pimeta2/pguide.html#op-amps | 23:04 |
drazak | that's what I mean | 23:04 |
drazak | so I'm trying to pick a single channel opamp that has similar voltage requirements as the AD823 | 23:05 |
katsmeow-afk | See below for comments on using a different type of chip in OPAG than in OPALR. | 23:05 |
drazak | yep | 23:06 |
drazak | I've read the whole thing :) | 23:06 |
drazak | "you may be forced to use a different opamp in OPAG than in OPALR" | 23:06 |
katsmeow-afk | well, they give parts numbers they recommend | 23:08 |
drazak | aye | 23:10 |
drazak | most of them aren't low voltage | 23:10 |
katsmeow-afk | but will they work at the low voltage, not are they speced for a low voltage as their max power | 23:11 |
katsmeow-afk | that gnd buffer is supposed to be operational at exactly 1/2 vcc, and not have any rail-to-rail swing | 23:12 |
drazak | yeah | 23:12 |
katsmeow-afk | lockup on power up is your only concern | 23:12 |
drazak | mhm | 23:14 |
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katsmeow-afk | i am sorry to say i disagree with a lot of his design there | 23:16 |
kanzure | http://fab.cba.mit.edu/academy/about/ | 23:16 |
kanzure | vocational tech school for the fab lab | 23:16 |
katsmeow-afk | i have found sonic differences (with even current buffers) in any resistance where he has R1 , above 100ohms | 23:17 |
katsmeow-afk | it's especially serious with fet input gain blocks where you are driving current to charge gate capacitances | 23:17 |
katsmeow-afk | the R and input capaciatance is it's own hf roll off | 23:18 |
katsmeow-afk | bipolar inputs aren't as bad for that, but then you get into offset and bias current requirements | 23:18 |
drazak | yeah | 23:19 |
katsmeow-afk | i've seen opamps bias up with signal, then drift down to 0v with no signal | 23:19 |
drazak | it's on parwith other portable headphone amps though | 23:19 |
genehacker | Marta Male Alemany? | 23:20 |
drazak | http://tangentsoft.net/audio/ppa/amp2/misc/schematic8.pdf for more highend | 23:20 |
katsmeow-afk | i once did a tape deck with flat responce 10hz to 25khz (metal high bias) , dc connection from tape head right to the output jacks, which sat at 0.000v , no offset | 23:20 |
genehacker | whoever they invited me to some event and never responded to my response | 23:21 |
katsmeow-afk | drazak, i'd use a wall wart, higher voltages, or series 2 "9v" batteries, eliminate the gnd generator, and have a wider choice of opamps | 23:21 |
drazak | katsmeow-afk: for at home use and while charging I'm going to use a decent power supply for it | 23:23 |
katsmeow-afk | 2 batteries will eliminate the need for input caps, etc | 23:23 |
drazak | decrease portability | 23:26 |
drazak | and the case for 2 batteries doesn't allow me to use a better pot, so it's not helping me with anything else | 23:26 |
katsmeow-afk | 2 batteries? you are tied to the audio cord anyhow | 23:27 |
katsmeow-afk | oh,, i didn'tknow the pot was a problem | 23:27 |
katsmeow-afk | too bad Fenchurch isn't in #seattlerobotics atm, he'd be who you could be talking to, it's his business | 23:28 |
drazak | hehe | 23:28 |
drazak | well, I'd prefer to use an ALPS RK27 instead of an ALPS RK097 | 23:30 |
drazak | the RK27 is much, much better, and I could use better input caps | 23:30 |
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kanzure | hey noah | 23:31 |
kanzure | we were playing around with opamp circuits | 23:32 |
Noahj | Ah, I think I might have one of those somewhere around here, I've never done anything with it | 23:33 |
katsmeow-afk | funny he doesn't say why not use ceramics in audio paths: they are temperature sensitive and microphonic | 23:33 |
drazak | katsmeow-afk: he does, other places | 23:34 |
katsmeow-afk | ok, i didn't see it on this page | 23:34 |
drazak | http://tangentsoft.net/audio/input-cap.html | 23:35 |
drazak | gah it's not that page either | 23:36 |
drazak | he says it somewhere | 23:36 |
katsmeow-afk | doesn't matter | 23:36 |
kanzure | Noahj: was wondering if you could blabber about fab academy | 23:36 |
Noahj | Hmm | 23:36 |
Noahj | The official spiel's a lot more informative than I am right now | 23:36 |
Noahj | http://fab.cba.mit.edu/academy/about/ | 23:37 |
katsmeow-afk | the specs on the buffer contradict what he says about loading the opamp output : http://focus.ti.com/lit/ds/symlink/buf634.pdf page4 shows less phase offset with heavier load | 23:38 |
drazak | katsmeow-afk: he says a couple places that the only ceramics you should ever have in audio are C0G, NP0 | 23:39 |
drazak | I think in the page for working with cranky opamps | 23:39 |
* katsmeow-afk nods | 23:40 | |
drazak | and that those aren't ideal, but if that's all you have room to use and you need them | 23:40 |
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