highaltitude.log.20080506

[00:02] <fnoble> hi Laurenceb, did you call for me earlier?
[00:02] <Laurenceb> doesnt matter
[00:02] <Laurenceb> I was going to ask you how much QM you study :P
[00:03] <Laurenceb> Was confused about something really basic :-/
[00:03] <Laurenceb> but got it now
[00:03] <Laurenceb> anyway, do you do much QM ?
[00:03] <fnoble> we do some basics this year
[00:04] <fnoble> weve just finished doing some simple solutions to the shrodinger eqn
[00:04] <Laurenceb> ok
[00:04] <fnoble> only time invariant stuff
[00:05] <Laurenceb> I found that not too bad... its just some of the notation and terminology that confuses me
[00:05] <fnoble> yeah, seems to be the flavour of qm, its ok if you dont think too much about what you are actually doing
[00:05] <Laurenceb> which is rather worrying at this stage :-/
[00:06] <Laurenceb> lol yes
[00:06] <Laurenceb> how long before you graduate?
[00:07] <fnoble> dunno yet, have to decide if i want to stay here for 4 years
[00:07] <fnoble> only a lowly first year
[00:08] <fnoble> your in your third year right?
[00:08] <Laurenceb> fourth
[00:09] <Laurenceb> not that my knowledge reflects that :P
[00:09] <fnoble> heh, thinking of doing a postgrad course of some kind?
[00:10] <Laurenceb> phd studentship with SSTL at surrey uni
[00:10] <Laurenceb> working on galileo
[00:10] <fnoble> oh sweet
[00:10] <Laurenceb> should be more fun that this :-( I'm getting very bored with being here after 4 years
[00:12] <Laurenceb> the same schedule ect for 4 years gets very tedious
[00:13] <fnoble> yeah i can imagine
[00:13] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc:
[00:16] flowolf (n=flowolf@unaffiliated/flowolf) joined #highaltitude.
[00:18] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[00:26] <fnoble> hi edmoore
[00:27] <Laurenceb> hmm pomegranate
[00:28] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc:
[00:28] Tigga (n=chatzill@pc-232-235-60.magd.cam.ac.uk) left irc: Read error: 110 (Connection timed out)
[00:41] <Laurenceb> fboble: you got your eee pc from ebuyer?
[00:42] <fnoble> yeah
[00:42] <Laurenceb> are they ok with delivery ect?
[00:43] <Laurenceb> I'm thinking of getting http://www.ebuyer.com/product/126743
[00:43] <fnoble> yeah, got it next morning ordering at 4pm
[00:43] <Laurenceb> looks very good value
[00:43] <Laurenceb> nice
[00:43] <fnoble> looks like very good value!
[00:44] <Laurenceb> :P
[00:44] <fnoble> for you or a balloon :)
[00:44] <Laurenceb> indeed
[00:44] <Laurenceb> I need a camera anyway, but that could go on a balloon as well
[00:49] fuzzylugnut (n=poofy@134.50.220.160) joined #highaltitude.
[00:49] <fuzzylugnut> Hey
[00:49] <fnoble> hello fuzzylugnut
[00:51] <fuzzylugnut> did any of you guys track saturay's launch on findu?
[00:52] <fuzzylugnut> i don't know if we got on the internet with the packets or not
[00:56] <fuzzylugnut> hmm
[00:56] <fuzzylugnut> looks like 1 packet did
[01:01] <fuzzylugnut> the gumstix and UHX-1 serial transceiver worked beautifully
[01:02] <fuzzylugnut> i was able to cut the balloon shards free with a pyro cutdown at 75,000 ft.
[01:02] <fuzzylugnut> data was taken... I am happy.
[01:02] <fnoble> awesome, well done
[01:02] <fuzzylugnut> however I really want to move to GSM as the bidirectional communications
[01:02] <fuzzylugnut> Thanks
[01:03] <fnoble> GSM isnt good above 1km i think
[01:04] <fuzzylugnut> because of the transmit power or what?
[01:04] <fnoble> although we have good results using a gsm module for backup when the payload lands
[01:04] <fnoble> i think it gets confused because it sees too mny cells
[01:04] <fuzzylugnut> hmm
[01:04] <fuzzylugnut> but at altitude its no good?
[01:04] <fuzzylugnut> oh
[01:04] <fnoble> its saved us several times the radio cut out, it just texts us the gps coords
[01:05] <fuzzylugnut> cool
[01:06] <fuzzylugnut> I was really hoping I could call it when its at 70+ kft
[01:06] <fnoble> yeah it would save a lot of hastle
[01:07] <fuzzylugnut> but it just doesn't work?
[01:07] <akawaka> nope
[01:07] <fuzzylugnut> lame.
[01:07] <fuzzylugnut> really lame.
[01:08] <akawaka> where are you fuzzylugnut ?
[01:08] <fnoble> its ok for you guys in the us, you can just use lots of radio power :)
[01:08] <fuzzylugnut> US
[01:08] <akawaka> you should get your ham license
[01:08] <fnoble> we are limited to 10mw
[01:08] <fuzzylugnut> get a ham license : 3
[01:08] <akawaka> its very simple and it opens up a whole bunch of options
[01:08] <fuzzylugnut> I have mine
[01:09] <fuzzylugnut> the serial link we used on this flight was on 2m.
[01:09] <fuzzylugnut> I want higher bandwith though
[01:09] <akawaka> i see
[01:09] <akawaka> yeah, going above 9600bps is gonna be tough
[01:10] <fuzzylugnut> *nod*
[01:10] <akawaka> fuzzylugnut: what transceiver did you use on the balloon?
[01:10] <fnoble> have to do it the clever way, error correcting codes and such
[01:10] <fuzzylugnut> UHX-1 from radiometrix
[01:10] MetaMorfoziS (n=avr@3e44b94c.adsl.enternet.hu) left irc: "who the fuck is alice?"
[01:11] <fuzzylugnut> it has a dumb modem built in, 500mw tx
[01:11] <fuzzylugnut> and its pretty small
[01:11] <akawaka> oh interesting
[01:11] <fnoble> what data rate were you using before?
[01:12] <akawaka> you kept in contact with it?
[01:13] <fuzzylugnut> this uses 1200bps
[01:13] <fuzzylugnut> and yeah, I kept hitting enter, and it would send back the linux prompt
[01:13] <akawaka> what kind of antenna?
[01:14] <fuzzylugnut> cartop, but I was using an arrow antenna too
[01:14] <fuzzylugnut> there were points where I couldn't get it exactly when i wanted it, but the flight was very very rough and jerky, so that could be a reason
[01:14] <fuzzylugnut> otherwise I was very pleased
[01:14] <akawaka> thats pretty cool
[01:14] <fuzzylugnut> when you type a charachter in kermit, it sends it, then the gumstix echos it back
[01:15] <akawaka> we abandoned the packet radio stuff because we couldn't get it working correctly
[01:15] <fuzzylugnut> it would be tricky to do it from scratch
[01:15] <akawaka> we did it with a handheld transceiver and soundmodem in linux
[01:15] <fuzzylugnut> the UHX-1 combines everything into a little shiny box
[01:15] <fuzzylugnut> ooh man
[01:15] <fuzzylugnut> yeah, thats inventive, but sounds hard
[01:16] <fnoble> yeah, we just get our payload to continously send data packets, could get 50-300 ish baud :)
[01:16] <fuzzylugnut> *nodnods*
[01:16] <akawaka> fuzzylugnut: is it afsk?
[01:16] <fnoble> dont have uplink yet, need a ham ticket
[01:16] <fuzzylugnut> akawaka: I don't know, I believe so. check the datasheet
[01:18] <fuzzylugnut> when the signal is poor, it doesn't give you strange charachters on the screen, its all or nothing
[01:18] <fuzzylugnut> it must have some sort of checksum thing in it.
[01:18] <akawaka> what are you using at the receiving end?
[01:18] <fuzzylugnut> another uhx-1
[01:18] <akawaka> i see
[01:18] <fuzzylugnut> hooked up to a serial to usb chip from linxtechnologies
[01:19] <fuzzylugnut> I'll have pics up once I move to TN
[01:19] <fuzzylugnut> the only prob is the uhx-1 runs about 200 a pop
[01:19] <fuzzylugnut> but nasa expanded our group's funding another grand, so horray
[01:20] <fuzzylugnut> bbiab, picking up dinner
[01:32] flowolf (n=flowolf@unaffiliated/flowolf) left irc: "Leaving"
[01:50] <fuzzylugnut> back
[01:51] <fuzzylugnut> I'm really sad that gsm doesn't work at altitude
[01:52] <fuzzylugnut> that makes me a sad panda.
[02:11] DoYouKnow (n=mike@adsl-68-75-57-254.dsl.emhril.ameritech.net) joined #highaltitude.
[02:19] <fuzzylugnut> DYK
[02:24] <DoYouKnow> hi
[02:24] <DoYouKnow> still waiting to fly a north coast rocketry rocket that I have, and a gas-powered R/C airplane
[02:24] <DoYouKnow> both were gifts to me, but haven't flown them yet
[02:27] <DoYouKnow> waiting for a good opportunity when the rest of my family is available, so I have some audience
[02:33] <fuzzylugnut> Cool
[02:33] <fuzzylugnut> best of luck!
[02:35] <DoYouKnow> thanks
[02:36] <fuzzylugnut> what size is the rocket?
[02:47] <DoYouKnow> it's like 4'
[02:48] <fuzzylugnut> cool.
[03:30] <fuzzylugnut> however real-life tests showed there is absolutely no GSM reception above 650m (2100ft). So it's not like in the movies! Knowing that, the GSM phone still is a useful recovery aid
[03:30] <fuzzylugnut> ;_;
[03:32] <fuzzylugnut> I can't believe this. : (
[03:41] <DoYouKnow> are you going on a big climbing trip?
[03:42] fnoble (n=fnoblef@fn217.quns.cam.ac.uk) left irc: Remote closed the connection
[03:44] <fuzzylugnut> no
[03:45] <fuzzylugnut> I was looking to send it up in a balloon
[03:52] <DoYouKnow> oh heh :)
[03:52] <DoYouKnow> well, you can always use a laser pointer
[03:52] <DoYouKnow> with some kind of optical attachment
[03:52] <DoYouKnow> maybe a disco ball sort of thing
[03:53] <DoYouKnow> and you could transmit signals on the light beam
[03:56] <DoYouKnow> hmmm
[03:56] <DoYouKnow> how would you best do that
[03:56] akawaka (n=akawaka@external.treyarch.com) left irc: Read error: 110 (Connection timed out)
[03:56] <DoYouKnow> maybe with an intensely bright diffuse beam, and a telescope
[03:56] <DoYouKnow> yeah, that's a better idea
[03:56] <DoYouKnow> you could use ccd imaging software to decode the binary bit
[03:56] <DoYouKnow> s
[03:57] <DoYouKnow> you could also probably use instead an infrared laser then put an infrared camera up there
[03:57] <DoYouKnow> so that while transmitting the data, you have an imaging beam
[03:58] <fuzzylugnut> are you high?
[03:59] <DoYouKnow> no
[03:59] <DoYouKnow> I'm serious. you could use a telescope and a bright beam of light
[04:00] <DoYouKnow> to transmit the data
[04:00] <fuzzylugnut> :o
[04:00] <DoYouKnow> what kind of data are you trying to transmit?
[04:00] <DoYouKnow> audio?
[04:00] <DoYouKnow> edmund scientifics sells a audio-over-fiber kit
[04:00] <DoYouKnow> look at that
[04:02] <DoYouKnow> it might require some knowledge of optics
[04:02] <fuzzylugnut> my tapeworm has knowledge of optics
[04:09] <natrium42> XD
[04:09] <natrium42> i want to make an optical tracker
[04:09] <natrium42> perhaps blinking a bright light would transfer data, eh?
[04:09] <DoYouKnow> yeah
[04:09] <natrium42> one way
[04:10] <natrium42> laser would be very very hard, though :P
[04:10] <DoYouKnow> I wouldn't expect more than like 3 bits per second though
[04:10] <DoYouKnow> although that's good for something like temperature
[04:10] <DoYouKnow> I figure
[04:10] <natrium42> would be fun to play with
[04:12] <DoYouKnow> and with a regular telescope and a high intensity green laser pointer shining into a glass bead, it would probably work at least a mile, I figure
[04:12] <natrium42> glass bead?
[04:13] <natrium42> why not use a real light? :P
[04:14] <DoYouKnow> figured that if you were looking for a single wavelength, esp for tracking - that would be a good option
[04:14] <natrium42> hmm, you might have a point
[04:14] <DoYouKnow> using a laser
[04:15] <natrium42> is it easy to get a filter that only lets through that particular wavelength?
[04:15] <DoYouKnow> yeah
[04:15] <DoYouKnow> but for a flashlight, it will get pretty dim. the filters are dark... like my telescope filters, are pretty dark
[04:15] <DoYouKnow> I don't know how much light they transmit
[04:16] fuzzylugnut (n=poofy@134.50.220.160) left irc: "sad brain"
[04:17] <DoYouKnow> as a precise percent
[04:17] <natrium42> do you have a computerized scope?
[04:17] <DoYouKnow> yeah
[04:17] <natrium42> what mount?
[04:17] <DoYouKnow> alt+azimuth
[04:17] <DoYouKnow> lx90
[04:17] <natrium42> nice
[04:18] <natrium42> i was thinking about getting one to try optical tracking of balloons
[04:19] <DoYouKnow> cool
[04:35] akawaka (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) joined #highaltitude.
[05:02] Laurenceb (n=laurence@dhcp37-133.sthughs.ox.ac.uk) left irc: Remote closed the connection
[05:08] Laurence1 (n=Laurence@dhcp38-010.sthughs.ox.ac.uk) joined #highaltitude.
[05:16] Laurence1 (n=Laurence@dhcp38-010.sthughs.ox.ac.uk) left irc: Read error: 104 (Connection reset by peer)
[05:52] akawaka (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) left irc: Read error: 110 (Connection timed out)
[06:08] Tiger^ (i=tygrys@moo.pl) left irc: Remote closed the connection
[06:08] Tiger^ (i=tygrys@moo.pl) joined #highaltitude.
[06:16] DoYouKnow (n=mike@adsl-68-75-57-254.dsl.emhril.ameritech.net) left irc:
[08:20] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[08:57] Tigga (n=chatzill@pc-232-235-60.magd.cam.ac.uk) joined #highaltitude.
[10:07] akawaka (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) joined #highaltitude.
[10:08] Akadecca (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) joined #highaltitude.
[10:26] akawaka (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) left irc: Read error: 110 (Connection timed out)
[10:31] Laurenceb (n=laurence@dhcp37-133.sthughs.ox.ac.uk) joined #highaltitude.
[10:44] Akadecca (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) left irc: Read error: 110 (Connection timed out)
[11:03] flowolf (n=flowolf@unaffiliated/flowolf) joined #highaltitude.
[11:39] fnoble (n=fnoblef@fn217.quns.cam.ac.uk) joined #highaltitude.
[14:16] fnoble (n=fnoblef@fn217.quns.cam.ac.uk) left irc: Read error: 110 (Connection timed out)
[14:25] natrium42 (n=alexei@CPE000625d867e2-CM0014045885be.cpe.net.cable.rogers.com) left irc: "pwned!"
[15:06] Simon-MPFH (n=simon@phantom.mpfh.co.uk) joined #highaltitude.
[15:24] MetaMorfoziS (n=avr@3e44b94c.adsl.enternet.hu) joined #highaltitude.
[16:34] natrium42 (n=alexei@libnaa105.uwaterloo.ca) joined #highaltitude.
[16:35] flowolf (n=flowolf@unaffiliated/flowolf) left irc: "Leaving"
[16:54] Laurenceb (n=laurence@dhcp37-133.sthughs.ox.ac.uk) left irc: Read error: 104 (Connection reset by peer)
[17:14] natrium42 (n=alexei@libnaa105.uwaterloo.ca) left irc: "pwned!"
[17:16] natrium42 (n=alexei@libnaa105.uwaterloo.ca) joined #highaltitude.
[17:25] Akadecca (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) joined #highaltitude.
[17:43] Laurenceb (n=laurence@dhcp37-133.sthughs.ox.ac.uk) joined #highaltitude.
[17:45] <Laurenceb> I just stuck some photos on the wiki
[17:45] <natrium42> bah, i just checked the wiki a few mins ago
[17:45] <natrium42> :D
[17:47] <Laurenceb> hmm evolution is behaving strangely
[17:47] <natrium42> so the pcb arrived?
[17:48] <Laurenceb> yes
[17:48] <Laurenceb> I have 6 of those boards :P
[17:48] <Laurenceb> if I highlight the window, it takes over the entire screen
[17:49] <natrium42> my whole system is messed up
[17:49] <natrium42> i upgraded to hardy yesterday
[17:49] <natrium42> need to do a clean install....
[17:49] <Laurenceb> hardy=7.10 ?
[17:49] <natrium42> 8.04
[17:49] <Laurenceb> ah
[17:49] <Laurenceb> I have 7.10
[17:50] <natrium42> yes, that's what i had before
[17:50] <natrium42> edgy
[17:50] <Laurenceb> I believe evolution doesnt like compiz
[17:50] Hiena (n=Hiena@81.93.195.181.datatrans.hu) joined #highaltitude.
[17:51] <natrium42> my laptop is too crappy to run compiz
[17:51] <Hiena> Good evening!
[17:51] Akadecca (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) left irc: Read error: 110 (Connection timed out)
[17:51] <natrium42> hi
[17:51] <natrium42> and i am off for astrophysics lecture
[17:51] natrium42 (n=alexei@libnaa105.uwaterloo.ca) left irc: "pwned!"
[17:51] <Laurenceb> cool
[17:51] <Hiena> Hey, natrium42, any other reason from the eyecandy to run compiz?
[17:52] <Laurenceb> I think the answer would be no
[18:02] <Laurenceb> it is a bit ott
[18:03] <Laurenceb> but then again, look at osx
[18:06] borism (n=boris@195-50-204-250-dsl.krw.estpak.ee) left irc: Connection reset by peer
[18:06] <Hiena> Well, when i pick up a hammer i'm usually uninterested, is it chrome plated or not.
[18:14] <Laurenceb> lol :P
[18:23] akawaka (n=akawaka@external.treyarch.com) joined #highaltitude.
[19:18] jcoxon (n=jcoxon@80.88.222.59) joined #highaltitude.
[19:24] Hiena (n=Hiena@81.93.195.181.datatrans.hu) left irc: "-=Alkoholmentes-sör és repülõgép-szimulátor, biztos út a guminõ felé=-"
[19:36] fnoble (n=fnoblef@fn217.quns.cam.ac.uk) joined #highaltitude.
[19:37] <jcoxon> evening fnoble
[19:37] <Laurenceb> hello jcoxon
[19:38] <Laurenceb> bbl
[19:38] <jcoxon> hey Laurenceb
[19:41] <jcoxon> haha
[19:41] <akawaka> Laurenceb: how difficult would it be for me to make a 2uH inductor that operates at 10Mhz or so
[19:41] <akawaka> is it something i should just avoid
[19:42] <fnoble> jcoxon, hello
[19:44] <fnoble> bbl
[19:49] <jcoxon> haha
[19:53] jcoxon (n=jcoxon@80.88.222.59) left irc: "Leaving"
[20:01] fnoble (n=fnoblef@fn217.quns.cam.ac.uk) left irc: Read error: 110 (Connection timed out)
[20:02] jcoxon (n=jcoxon@80.88.222.59) joined #highaltitude.
[20:35] fnoble (n=fnoblef@62.49.66.13) joined #highaltitude.
[20:37] <fnoble> evning all
[20:39] <jcoxon> hi fnoble
[20:39] <jcoxon> 'bbl'
[20:39] <jcoxon> :-p
[20:41] <fnoble> yeah, just walked up to the computer lab to do some work
[20:44] <jcoxon> its okay
[20:57] <Laurenceb> hello
[20:57] <Laurenceb> back
[20:58] <Laurenceb> sorry, was cycling up the canal :D
[20:59] <Laurenceb> akawaka: do you have an LCR ?
[20:59] <akawaka> i have a scope and a function generator
[20:59] <Laurenceb> hmm ok
[20:59] <Laurenceb> well its not too hard
[21:00] <Laurenceb> just make a potential divider, find the amplitude and phase and fiddle with some complex impedances
[21:02] <Laurenceb> you can use the basic equations to find the rough size ect
[21:06] jcoxon (n=jcoxon@80.88.222.59) left irc: "Leaving"
[21:23] <fnoble> brb
[21:30] natrium42 (n=alexei@CPE000625d867e2-CM0014045885be.cpe.net.cable.rogers.com) joined #highaltitude.
[21:38] <fnoble> back
[21:51] Simon-MPFH (n=simon@phantom.mpfh.co.uk) left irc: "Leaving"
[21:52] <Laurenceb> theres some good stuff on the cu spaceflight site
[21:52] <Laurenceb> like the nova5 video
[21:55] <Laurenceb> much less spin than MiHAB3
[21:55] <Laurenceb> must be due to just a single payload
[22:01] <fnoble> yeah, we have quite a few more videos that never got uploaded
[22:01] <fnoble> must sort that out sometime
[22:04] <Laurenceb> what did you use?
[22:04] <Laurenceb> camcorder or hacked camera?
[22:07] jcoxon (n=jcoxon@80.88.222.59) joined #highaltitude.
[22:09] <fnoble> it was an ultra cheap 5mp compact camera
[22:09] <fnoble> hacked so the flight computer could make it take a snapshot or a video
[22:09] <jcoxon> hey guys
[22:09] <fnoble> hi
[22:09] <Laurenceb> interesting, did you have to control all the button inputs?
[22:10] <fnoble> just the shutter and mode buttons i think
[22:10] <fnoble> it was one that henry hacked
[22:10] <Laurenceb> I see, same as the premier on ukhas1
[22:11] <Laurenceb> unfortunately thats now at the bottom of the north sea :(
[22:11] <fnoble> yes, i think it was a premier
[22:11] <Laurenceb> cool, it seems to be the best hab choice
[22:12] <fnoble> yeah, do they still make them
[22:12] <fnoble> want to give a catcam style camera a go though
[22:12] <fnoble> at some point
[22:13] <Laurenceb> there a 6MP one on ebay for £30
[22:14] <Laurenceb> catcam?
[22:14] <fnoble> google it, its a really small camera that someone has documented how to hack
[22:14] borism (n=boris@195-50-204-250-dsl.krw.estpak.ee) joined #highaltitude.
[22:14] <fnoble> he used it to make a camera for hus cats collar
[22:15] <fnoble> the camera model isnt actually called catcam
[22:15] <Laurenceb> lol thats the camera off MiHAB1
[22:17] Action: natrium42 got his cameras \o/
[22:17] <jcoxon> hmmm how to i send ctrl-z with echo
[22:18] <akawaka> ^Z ?
[22:19] <jcoxon> doesn't seem to work
[22:20] <fnoble> hmm, there is probably an escape char for it, but will depend on your terminal emulator?
[22:21] <jcoxon> its actually for AT commands
[22:24] <edmoore> Laurenceb: I'm not convinced it's just because of the single payload
[22:24] <jcoxon> echo -ne 'at+cmgs="xxxxxxxxxxxx"\r\n' >/dev/tty.usbmodem1a29
[22:24] <jcoxon> the prompt comes up
[22:24] <jcoxon> then i can echo the message
[22:24] <jcoxon> then you need to ctrl-z to send complete the message
[22:24] <edmoore> have seen plenty of US 'trains' which don't suffer the spinning issues
[22:24] <akawaka> \0NNN ?
[22:24] <akawaka> whats the octal for ctrl-z ?
[22:24] <Laurenceb> edmoore: maybe the rope used?
[22:24] <fnoble> edmoore, your back in churchill?
[22:24] <edmoore> my skype is playing up. if mc- sees this in the logs, can you email me?
[22:25] <edmoore> fnoble: yes, just got back
[22:25] <edmoore> but going to gym
[22:25] <fnoble> do you want to meet later?
[22:25] <edmoore> Laurenceb: quite possibly yes
[22:25] <fnoble> i have stuff to do for another hour or so
[22:25] <edmoore> i'll be in the gym till midnight - friends are doing some gym music on their 11-12 slot on CU Radio
[22:26] <Laurenceb> UKHAS1 was quite hastily assembled on the launchpad :P
[22:26] <edmoore> given me and chris constitute about 50% of their listenership
[22:26] <jcoxon> akawaka, \0NNN doesn't work
[22:27] <fnoble> i think you need to change NNN to the code for ctrl d
[22:27] <fnoble> which doesnt actually have a code itself
[22:28] <fnoble> but ctrl-d usually sends acsii char 4
[22:28] <fnoble> so \o004 might do it
[22:29] <jcoxon> fnoble, its ctrl-z though
[22:30] <fnoble> oh is see, lol, was thinking crtl-d is usually used for end of transmission
[22:31] <fnoble> apparently ctrl-z sends EOF which is ascii 26 in decimal
[22:33] <jcoxon> man echo is suprisingly unhelpful
[22:35] <fnoble> \032 should do it
[22:35] <fnoble> from bash anayway
[22:35] <jcoxon> yup
[22:35] <jcoxon> got it
[22:36] <jcoxon> thanks fnoble and akawaka
[22:47] <fnoble> brb
[23:04] phatmonkey (n=ben@81.2.121.150) joined #highaltitude.
[23:07] phatmonkey (n=ben@81.2.121.150) left irc: Client Quit
[23:07] phatmonkey (n=ben@81.2.121.150) joined #highaltitude.
[23:08] mc- (n=mfcastle@cpc4-glfd1-0-0-cust538.glfd.cable.ntl.com) joined #highaltitude.
[23:09] <mc-> akawaka
[23:09] <akawaka> hey
[23:10] <mc-> are you building the transmitter on the website?
[23:10] <mc-> forgotten the url
[23:10] <akawaka> which?
[23:10] <akawaka> http://web.mit.edu/bgelb/www/balloon/hfbeacon/
[23:10] <akawaka> that one?
[23:10] <mc-> yes
[23:10] <mc-> I've built it
[23:10] <mc-> haven't test it yet
[23:10] <akawaka> same frequency?
[23:10] <mc-> yes
[23:10] <akawaka> just ordered parts for it
[23:11] <mc-> I modified the inductor values, so it uses standard values
[23:11] <akawaka> but i'm hoping to adapt it to 40meters
[23:11] <mc-> changed L? to 3uH
[23:11] <mc-> it's a class E amp, so you need to make several changes
[23:11] <mc-> why do you want 40m?
[23:12] <akawaka> i'm not licensed for that 10mhz band
[23:12] <mc-> noisy band with lots of interferers
[23:12] <mc-> I'll check the design eqns
[23:12] <mc-> can you find someone who is licensed for that band?
[23:13] <mc-> which freq on 40m?
[23:13] <akawaka> 7Mhz
[23:13] <akawaka> maybe i can upgrade my license
[23:13] <mc-> 7.0000MHz?
[23:13] <akawaka> 7.025 - 7.125
[23:15] <mc-> for 7.05MHz C1 is 0.1nF
[23:15] <mc-> C2=175pF
[23:15] <mc-> L2=4.3uH
[23:17] <mc-> alternative values L2=3.67uH, C1=111pF, C2=226pF
[23:17] <akawaka> C3, C4 and L3 stay the same?
[23:18] <mc-> they are the filter network, they change as well...
[23:18] <akawaka> C1 seems like a pretty big change from 47pf to .1nf
[23:18] <mc-> there should be the eqns for pi filter design on the web
[23:20] <akawaka> thats like a 12Mhz lpf or so, right?
[23:20] <mc-> yes, C1 is the resonating cap so that the amp is very efficient
[23:21] <mc-> 12MHz cutoff? it's probably closer to 10MHz cutoff
[23:22] <akawaka> messing with this: http://www.pronine.ca/butlf1.htm
[23:22] <mc-> I suggest building the circuit for 10MHz first, and seeing the waveforms on the scope
[23:22] <akawaka> yeah, thats what i was planning on doing
[23:22] <akawaka> thanks for the numbers, thats awesome
[23:22] <akawaka> how do you go about calculating them?
[23:24] <mc-> Ben at MIT sent me his spreadsheet
[23:24] <mc-> I've been reading about class E for some time
[23:26] <Laurenceb> C1 is the resonating cap?
[23:26] <Laurenceb> whats C2 for ?
[23:26] <Laurenceb> I thought C2,L2 formed a resonant circuit
[23:27] <akawaka> pain in the ass trying to find inductors
[23:27] <fnoble> back
[23:27] <fnoble> hi mc-
[23:28] <mc-> hi fnoble
[23:28] <mc-> C102 is part of the network
[23:29] <Laurenceb> along with L102?
[23:29] <mc-> L102 is part of the filter I think
[23:30] <mc-> sorry you're right
[23:30] <mc-> L102 is part of the class E network
[23:31] <mc-> the 3 components together resonate at 10MHz
[23:31] <mc-> and the capacitance of the transistor also is taken into account
[23:31] <Laurenceb> C101, L102, C102 ?
[23:31] <mc-> yes
[23:32] <Laurenceb> ok
[23:32] <akawaka> and then C3, C4, L1 are to filter the harmonics, right?
[23:33] <Laurenceb> thats a Pi network?
[23:34] <mc-> yes, http://www.pronine.ca/butlf1.htm gives values fairly close
[23:34] <mc-> it's probably a chebyshev as that has better cutoff
[23:37] <mc-> got to go now
[23:37] <akawaka> thanks again mc- !
[23:37] <Laurenceb> cya
[23:37] <mc-> btw, I built it on a piece of old pcb, didn't take too long
[23:38] <akawaka> yeah, it doesn't look that complex to built
[23:38] <akawaka> build
[23:38] <mc-> don't think you need the 74HC540 in front
[23:38] flowolf (n=flowolf@unaffiliated/flowolf) joined #highaltitude.
[23:38] <mc-> 1 TTL gate is enough to drive
[23:38] <akawaka> thats one of the only components i have:)
[23:38] <mc-> the 2n7000s
[23:39] <mc-> you can just put the 2n7000s on top of each other
[23:39] mc- (n=mfcastle@cpc4-glfd1-0-0-cust538.glfd.cable.ntl.com) left irc:
[23:41] phatmonkey (n=ben@81.2.121.150) left irc:
[23:41] phatmonkey (n=ben@scooby.firshman.co.uk) joined #highaltitude.
[23:41] <edmoore> hi mc- again if you catch this in the logs, my skype doesn't seem to let me do anything, it just tells me you're sending messages that i can't receive. so it'd be best to stick it all in an email, and I'll try re-installing skype
[23:41] jcoxon (n=jcoxon@80.88.222.59) left irc: Read error: 104 (Connection reset by peer)
[23:42] phatmonkey (n=ben@scooby.firshman.co.uk) left irc: Client Quit
[23:42] phatmonkey (n=ben@scooby.firshman.co.uk) joined #highaltitude.
[23:47] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc:
[23:49] Tigga (n=chatzill@pc-232-235-60.magd.cam.ac.uk) left irc: Read error: 110 (Connection timed out)
[00:00] --- Wed May 7 2008