highaltitude.log.20090313

[00:00] <Laurenceb> natrium42: nice work
[00:00] <Laurenceb> natrium42: whats the problem with the venus chip?
[00:03] <shellevil> he was saying yesterday he had no clue how to do antenna matching, and it wasn't working
[00:03] <Laurenceb> its not very hard ;-/
[00:04] <Laurenceb> especially with off the shelf hardware
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[01:01] <Laurenceb> hi fergus
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[02:10] <natrium42> Laurenceb, it's not easy for GPS chip antennas :S
[02:10] <Laurenceb> whats the problem?
[02:10] <Laurenceb> is the input 50 ohm?
[02:11] <Laurenceb> to the venus
[02:12] <natrium42> yes
[02:12] <natrium42> but it's a run of only a few mm
[02:13] <Laurenceb> still best to match at gps frequency
[02:13] <Laurenceb> so venus - 50 ohm line - ant
[02:13] <natrium42> yes
[02:13] <Laurenceb> but you need to match to the ant
[02:13] <Laurenceb> whats the output impedance of the antenna?
[02:13] <natrium42> but gps chip antennas need to be matched for the particular PCB design
[02:13] <Laurenceb> yeah
[02:14] <Laurenceb> arent there reference designs in the datasheet?
[02:14] <natrium42> it's irrelevant
[02:14] <natrium42> any pcb design will be different
[02:14] <natrium42> and need matching
[02:14] <Laurenceb> hmm ok
[02:14] <Laurenceb> so you need a matching circuit
[02:15] <natrium42> i should solder the helix antenna pcb
[02:15] <natrium42> it should work without problems
[02:15] <Laurenceb> then tweak the component values
[02:15] <natrium42> yeah
[02:15] <Laurenceb> until it works well
[02:15] <Laurenceb> a bt hard to test
[02:15] <natrium42> but i don't have the equip
[02:15] <Laurenceb> hmm
[02:15] <natrium42> antenova guys do it for $500
[02:15] <natrium42> for their antennas
[02:15] <Laurenceb> if you find the positions of the sats
[02:15] <natrium42> not too bad
[02:16] <Laurenceb> then can venus give you signal to noise?
[02:16] <natrium42> not sure
[02:16] <shellevil> you can for a test point a dish at a sat
[02:16] <shellevil> nat: do you have NMEA out?
[02:16] <natrium42> the way they do it use a gps frequency transmitter
[02:16] <natrium42> and measure the antenna performance
[02:16] <shellevil> does it put out GPGSV?
[02:16] <natrium42> in circuit
[02:16] <shellevil> nat: there is a cheat
[02:16] <Laurenceb> sure
[02:16] <Laurenceb> yeah we have kit here
[02:16] <natrium42> shellevil, yeah
[02:16] <Laurenceb> natrium42: if you post it to me I could test it
[02:16] <shellevil> natrium42: 1m dish pointed at sat is some orders of magnitude higher signal
[02:17] <Laurenceb> you need some sort of signal strenght out of the venus to do it like that
[02:17] <natrium42> Laurenceb, hmm, i might take you up on your offer
[02:18] <Laurenceb> theres an anechoic chamber
[02:18] <Laurenceb> or whatever you call it
[02:18] <Laurenceb> with gps transmitter
[02:19] <natrium42> do you know how to use it?
[02:19] <Laurenceb> nope, I'm sure the guys who do ant testing wouldnt mind
[02:20] <Laurenceb> it its only a couple of tests we need to run
[02:20] <Laurenceb> its only a big alu case
[02:21] <Laurenceb> lines with microwave absorbant foam
[02:21] <Laurenceb> *lined
[02:21] <natrium42> cool
[02:21] <shellevil> Laurenceb: GPGSV lines give you signal strength - if the venus will put them out
[02:21] <Laurenceb> then theres servo pointed antennas at either end
[02:21] <natrium42> i am testing with an antennova antenna atm
[02:21] <Laurenceb> ah ok
[02:21] <natrium42> maybe it will work...
[02:22] <Laurenceb> if you can get signal strenght out you can do it fine
[02:22] <Laurenceb> just go outside to a winde open space and track sats quite high up
[02:22] <Laurenceb> then work out their distance and do the maths
[02:26] <natrium42> hmm
[02:29] <Laurenceb> http://greenerbuildings.com/blog/2009/03/11/buckingham-palace-tops-list-least-green-buildings-london
[02:29] <Laurenceb> lol @ number 2
[02:31] <natrium42> haha
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[02:54] <Laurenceb> http://prime.isthe.com/no.index/chongo/merdigit/long-m43112609/prime.html
[02:56] <Laurenceb> hmm septentrigintillion
[02:58] <shellevil> long prime is long.
[02:59] <Laurenceb> heh quattuormilliamilliaducentreoctoginmilliasexvigintillion
[04:02] <edmoore> so.... lab reports suck
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[07:35] <jcoxon> morning all
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[07:56] <mc-> morning jcoxon, what needs doing for Halo?
[07:58] <jcoxon> hey mc-
[07:58] <jcoxon> i'm not really sure right now
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[07:59] <jcoxon> i've got clinic this morning but this afternoon i'll have a think and write a list of jobs
[07:59] <jcoxon> one thing is to have an IRC meeting sometime - think we need to discuss the intergration of our various components
[07:59] <jcoxon> right better be off
[07:59] <jcoxon> bbl
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[12:00] <natrium42> edmoore, still up?
[12:00] <edmoore> i've transitioned into 'tomorrow'
[12:00] <natrium42> hehe
[12:00] <edmoore> i am pretty disorientated though
[12:00] <natrium42> did you finish it?
[12:03] <edmoore> yep
[12:04] <edmoore> it's handed in
[12:04] <natrium42> cool, good job
[12:04] <natrium42> now get some sleep :P
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[14:09] <SpeedEvil> lau: when applying for a passport, do the backs of the photos need signed?
[14:09] <SpeedEvil> oh - he left
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[14:29] <natrium42> yo jcoxon
[14:31] <jcoxon> hey natrium42
[14:32] <jcoxon> hows it going?
[14:33] <natrium42> good
[14:33] <natrium42> should probably get some helium
[14:33] <natrium42> for test flight
[14:33] <jcoxon> yeah
[14:33] <jcoxon> do you know what the radio rules are in canada?
[14:34] <jcoxon> as in are we allowed to use HF in the air in Canada?
[14:34] <natrium42> hmm, i haven't heard that you can't
[14:34] <jcoxon> okay
[14:35] <natrium42> or should i wait for the tank to do a testflight?
[14:35] <jcoxon> tank?
[14:35] <jcoxon> ballast tank?
[14:35] <natrium42> yeah
[14:36] <jcoxon> ummm
[14:36] <jcoxon> not sure
[14:37] <jcoxon> how soon could you launch a test flight?
[14:38] <natrium42> by next weekend
[14:38] <natrium42> i could probably do this sunday if i tried
[14:39] <natrium42> weather outlook is good
[14:39] <jcoxon> hehe well i've still got a few things to sort out
[14:39] <jcoxon> like i need to get some thinner silicone tubing
[14:42] <jcoxon> so i'd go ahead
[14:43] <jcoxon> if i can get stuff sent to you next week them perhaps a second test flight (if you have time)
[14:44] <natrium42> k
[14:44] <natrium42> it's really just to test flight computer
[14:45] <jcoxon> best to test things gradually
[14:48] <jcoxon> what sort of comms will you use?
[14:48] <natrium42> spot and gm862-gps
[14:50] <jcoxon> no radio?
[14:51] <natrium42> yes, i don't have a yagi for it
[14:52] <jcoxon> hmm, got any 434mhz modules?
[14:52] <natrium42> no
[14:52] <natrium42> it's not an unlinced band here, afaik
[14:52] <jcoxon> really?
[14:53] <jcoxon> its ISM though
[14:53] <jcoxon> you could always make a Moxon out of coathangers
[14:53] <natrium42> 900MHz is unlicensed
[14:58] <jcoxon> well you could make a yagi for 900mhz
[14:58] <jcoxon> or at least a moxon (which is like a 2 element yagi)
[14:59] <natrium42> hmm, i will consider it
[14:59] <jcoxon> actually it would be tiny
[15:00] <jcoxon> thinking about the radio logic, we'll have HF on from launch till it reaches teh UK and then have the 70cm transmitter turn on after that
[15:01] <natrium42> ok, so some kind of vector polygon for UK
[15:01] <natrium42> it's fine to use HF over europe?
[15:02] <jcoxon> hmmm that i'm not sure about
[15:03] <jcoxon> it'll probably be different in each country
[15:03] <jcoxon> might be safer going with 70cm which will be fine
[15:04] <natrium42> you won't be able to get the signal though if it's far away
[15:05] <jcoxon> tis true
[15:05] <jcoxon> but if push comes to shove we could contact people to listen in
[15:06] <jcoxon> hmmmm i'm not sure
[15:06] <jcoxon> perhaps leave HF on over europe
[15:09] <natrium42> ok, helium is in stock
[15:09] <jcoxon> great
[15:09] <natrium42> i need to pick it up
[15:15] <jcoxon> hehe, i got the moxon calculator and stuck in the 900mhz
[15:15] <jcoxon> it would be 11cm x 4cm in size
[15:16] <natrium42> lul
[15:16] <natrium42> what's the gain?
[15:17] <jcoxon> http://www.moxonantennaproject.com/performance.htm
[15:18] <jcoxon> that page actually isn't that helpful
[15:20] <natrium42> i am pretty confident in the gm862-gps as a backup though
[15:20] <jcoxon> oh so am i
[15:20] <jcoxon> guess the spot will do the job of the radio
[15:21] <natrium42> yep, just with a ~8 min reporting delay
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[15:59] <SpeedEvil> natrium42: going to just ignore teh
[16:00] <natrium42> ?
[16:00] <SpeedEvil> the spot micro, or switch between it and the computer?
[16:00] <SpeedEvil> oh
[16:00] <SpeedEvil> you've desoldered it
[16:00] <natrium42> :D
[16:00] <SpeedEvil> guess that answers that
[16:00] <natrium42> it's possible to keep the micro
[16:01] <natrium42> but i don't really need it
[16:01] <SpeedEvil> I was wondering about something like a 555, giving half an hour to each, as a _really_ stupid backup.
[16:01] <natrium42> bbl
[16:01] <SpeedEvil> using the spot gps?
[16:01] <SpeedEvil> wave
[16:38] <jcoxon> hmmmm, my phone contract is coming to an end, any recommendations for a new phone?
[16:38] <SpeedEvil> I would say OpenMoko Freerunner, but that's not really a phone yet
[16:42] <SpeedEvil> One with good insurance, for when it accidentally gets used as a payload :)
[16:42] <jcoxon> hehe
[16:42] <jcoxon> i want gps
[16:42] <jcoxon> perhaps a nokia 5800
[16:42] Action: SpeedEvil wishes openmoko core team weren't such fucktards.
[16:43] <jcoxon> ouch
[16:43] <SpeedEvil> For example - 2 years ago - there was a mostly functional software stack - it sent and recieved calls and SMSs, and was a almost functional basic phone.
[16:44] <SpeedEvil> Then they decided with little input from the community to completely ditch that stack, and go for another one that they'd developed without any notice to the community other than 'cool things in the future' announcements
[16:45] <SpeedEvil> And it's only just gotten to the point that in some kernels it will actually suspend properly.
[16:45] <SpeedEvil> :/
[16:45] <SpeedEvil> Lots of people have been screaming 'fix the kernel+lowest levels, and get out of the way', but...
[16:45] <SpeedEvil> OTOH - phone with schematics.
[16:45] <jcoxon> i could make my own
[16:46] <jcoxon> especially as i have a gumstix goliath daughterboard...
[16:46] <SpeedEvil> at at least 2* the price of the FR
[16:46] <SpeedEvil> and more volume
[16:46] <SpeedEvil> single quantities of stuff costs lots.
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[16:46] <SpeedEvil> Laurenceb: hi.
[16:46] <Laurenceb> hi
[16:46] Action: SpeedEvil dropped passport off at doctors for signature.
[16:47] <Laurenceb> you mean photos?
[16:47] <SpeedEvil> photos, and they've got to fill bit in 'countersignatory'
[16:47] <jcoxon> SpeedEvil, if you waited 14months i could sign it for you
[16:47] <SpeedEvil> 'I am a doctor', ...
[16:47] <jcoxon> :-p
[16:47] <SpeedEvil> :)
[16:48] <SpeedEvil> The doctor?
[16:48] <Laurenceb> hopefully not an evil doctor
[16:49] <jcoxon> Laurenceb, me an evil doctor - never!
[16:49] <Laurenceb> yeah, i dont think dr evil was a medical doctor
[16:50] <jcoxon> phd me thinks
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[16:54] <SpeedEvil> jcoxon: http://www.sparkfun.com/commerce/product_info.php?products_id=287
[16:54] <SpeedEvil> plenty of room for GPS
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[16:56] <jcoxon> haha
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[17:27] <edmoore> afternoon all
[17:29] <Laurenceb> hi edmoore
[17:31] <natrium42> edmoore, did you catch some sleep? :P
[17:32] <edmoore> not yet
[17:32] <edmoore> may just try and synch up with normal cycle tonight
[17:32] <Laurenceb> how long have you been up?
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[17:33] <hallam> hey all
[17:33] <Laurenceb> hi hallam
[17:33] <hallam> edmoore: rocketgps board is flashing leds
[17:33] <edmoore> ok that's good news
[17:33] <Laurenceb> omg
[17:33] <edmoore> what was up with it?
[17:33] <edmoore> did it just need massaging?
[17:33] <Laurenceb> how much is assembled?
[17:34] <hallam> yeah crossworks was being annoying
[17:34] <Laurenceb> you have the SE4120 on yet?
[17:34] <hallam> Laurenceb: everything but the RF stuff is on, I'll put the rest on tonight
[17:34] Action: Laurenceb excited
[17:34] <hallam> don't anticipate any problems with the SE4120
[17:34] <Laurenceb> yeah
[17:35] <hallam> I'm really sceptical that we'll get anything useful with the chip antenna though
[17:35] <Laurenceb> natrium42: has had issues with chip antennas
[17:35] <Laurenceb> yeah
[17:35] <Laurenceb> matching is a pain
[17:35] <Laurenceb> apparently
[17:36] <hallam> the thing's tiny, I just think its collecting area isn't enough
[17:37] <Laurenceb> hmm it doesnt really work like that
[17:37] <Laurenceb> rf is weird stuff
[17:37] <hallam> to some extent I thought it did
[17:37] <Laurenceb> its not like optics
[17:37] <hallam> bigger patches are better than smaller patches
[17:37] <Laurenceb> well it'll be roughly unidirectional
[17:38] <Laurenceb> so down 3dB relative to a patch
[17:38] <Laurenceb> if it works properly
[17:38] <hallam> omnidirectional you mean?
[17:38] <Laurenceb> erm yes
[17:38] <Laurenceb> woops
[17:38] <hallam> yeah
[17:38] <hallam> but it's also maybe 1/20th the area of a typical patch
[17:38] <hallam> if that
[17:38] <Laurenceb> I dont think that matters
[17:39] <hallam> why do bigger patches work better than smaller patches then?
[17:39] <Laurenceb> less lossy
[17:39] <Laurenceb> due to the materials used in construction I guess
[17:39] <hallam> right
[17:40] <hallam> then by analogy I'd expect the chip to be very lossy because it's so small
[17:40] <Laurenceb> asI understand it transmitting is equivalent to receiving
[17:40] <Laurenceb> so size makes no difference to theoretical transmit efficiency
[17:41] <Laurenceb> only how well its matched, and loss
[17:41] <hallam> hrm
[17:41] <hallam> well
[17:41] <hallam> anyway
[17:41] <hallam> based on the experience of people on the sparkfun forums, i'm not too hopeful
[17:41] <Laurenceb> yeah
[17:41] <hallam> we'll see
[17:41] <Laurenceb> they may have been having matching issues
[17:42] <hallam> so might we
[17:42] <Laurenceb> yeah
[17:42] <hallam> I mean, we tried to make it 50R stripline, but..
[17:42] <Laurenceb> is the idea to have the board ready for the next flight?
[17:42] <Laurenceb> oh the stripline will be ok
[17:43] <Laurenceb> its the antenna impedance thats the problem
[17:43] <Laurenceb> and detuning
[17:43] <hallam> it ought to be ready for the next EARS
[17:43] <Laurenceb> ok
[17:43] <hallam> at least to the level where we can record data to the microSD
[17:43] <Laurenceb> yeah
[17:44] <hallam> I don't know how much time i'll have to work on the blackfin software in the near future, got exams coming up soon that I really have to pass
[17:44] <Laurenceb> this your final year?
[17:44] <hallam> yes
[17:44] <Laurenceb> cool, anything organised for next year?
[17:44] <hallam> no
[17:45] <Laurenceb> what are your plans?
[17:47] <hallam> figure it out after graduating
[17:47] <Laurenceb> fairdoos
[17:47] <hallam> i'm a lot better at thinking on my feet than planning ahead
[17:47] <jcoxon> found thunderbirds
[17:47] <jcoxon> save the world
[17:47] <Laurenceb> yeah I didnt do much research before applying for this
[17:47] <hallam> the blue peter tracy island was so cool
[17:47] <jcoxon> i made one
[17:48] <jcoxon> it was badly made
[17:48] <hallam> I think everyone did
[17:48] <hallam> paper mache
[17:48] <Laurenceb> probably better to make sure you know what your doing properly first
[17:48] <Laurenceb> hehe
[17:48] <akawaka> back to the future deloriane is parked outside my building
[17:48] <akawaka> at least a very good fan replica
[17:48] <hallam> nice
[17:49] <natrium42> jcoxon, http://images.ucomics.com/comics/db/2005/db051218.gif
[17:49] <natrium42> :P
[17:49] <natrium42> akawaka, pics or it didn't happen!
[17:49] <hallam> ok, ARM time
[17:49] <jcoxon> haha
[17:50] Nick change: hallam -> hallam_ARMing
[17:50] <jcoxon> hallam, is that like hammer time?
[17:50] Action: natrium42 sets hallam_ARMing up the THUMB
[17:51] <jcoxon> bbl
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[17:57] <Laurenceb> hallam_ARMing: I think Iworked out the antenna thing
[17:58] <Laurenceb> smaller ants rely more on resonance
[17:58] <Laurenceb> so they have smaller bandwidths
[17:59] <Laurenceb> and are more vulnerable to detuning
[18:00] <Laurenceb> this is why antennas for glonass/gps/compass/galileo are so large
[18:01] <Laurenceb> extremely large bandwidths
[18:02] <Laurenceb> anyone used the maxq?
[18:03] <SpeedEvil> the micro?
[18:03] <Laurenceb> looks like an interesting micro.. but not many tools
[18:03] <Laurenceb> yeah
[18:03] <Laurenceb> avr and msp seem to be very similar speed wise, but maxq is a lot faster
[18:04] <SpeedEvil> then there is stm32 for another oreder of magnitude
[18:04] <Laurenceb> yeah
[18:04] <Laurenceb> then again xmega is getting on for an order of magnitude better than standard avr
[18:05] <Laurenceb> and its supported by the same dev tools
[18:06] <Laurenceb> http://www.youtube.com/watch?v=B4ZYcgpm7X4
[18:07] <SpeedEvil> avr32 oisn't te same thing though
[18:07] <Laurenceb> yeah but its cool
[18:07] <SpeedEvil> IME, once you get >1 chip, at >10MHz, things get complex
[18:07] <SpeedEvil> and expensive
[18:08] <Laurenceb> http://www.youtube.com/watch?v=intHPIydC8E
[18:08] <Laurenceb> seems to have used a psp lcd
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[18:12] <Laurenceb> http://dma.elektroda.net/ngw100-psp-lcd/ngw100-psp-lcd.html
[18:12] <Laurenceb> no interface electronics at all :P
[18:18] <SpeedEvil> hmm
[18:18] <SpeedEvil> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=497-6049-ND
[18:18] <SpeedEvil> has dropped in price (in dollars) - stm32 dev kit
[18:18] <SpeedEvil> though same about in quid
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[18:48] <Laurenceb> natrium42: what happens with your venus modules?
[18:48] <Laurenceb> they just cant aquire any sats?
[18:48] <natrium42> yes, with chip antennas
[18:48] <natrium42> i didn't try with regular antennas yet
[18:48] <natrium42> but it should work
[18:49] <Laurenceb> I see, nothing, even outside in open space?
[18:49] <natrium42> correct
[18:49] <natrium42> bandwidth is small, so they need to be tuned to the particular device
[18:49] <Laurenceb> :-/
[18:49] <natrium42> even plastic casing matters
[18:49] <Laurenceb> yeah
[18:49] <natrium42> how they measure it is cut a hole into the plastic case
[18:49] <Laurenceb> those things suffer from detuning
[18:49] <natrium42> and connect some coax
[18:50] <natrium42> i ordered some tiny active patch antennas
[18:50] <natrium42> 10x10x6mm
[18:50] <natrium42> might use them instead of bothering with chip antennas
[18:51] <natrium42> (btw, they can detune after some use)
[18:51] <natrium42> so helix or patch seems to be the best
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[19:21] <Laurenceb> just been testing the mni rogallo cutodwn
[19:21] <Laurenceb> works very nicely :P
[19:21] <Laurenceb> takes < 2seconds
[19:37] <SpeedEvil> :)
[19:40] <SpeedEvil> http://www.mauve.plus.com/pict0224.jpg - just been drilling lots of holes
[19:42] <SpeedEvil> The wall to the left gets some 2cm*2cm batten up it, to space insulation off the walls, the insulation gets packed out more or less to the outside of the beams, then new plasterboard. The chipboards at the bottom get put under the floorboard joists, and then insulation on top of it, then floorboards.
[19:46] <Laurenceb> henry
[19:46] <Laurenceb> hes going to get buried
[19:46] <SpeedEvil> :)
[19:47] <SpeedEvil> This is actually an 'internal' wall - but it's going to be cold, as it goes all the way up to the uninsulated roof.
[19:48] <SpeedEvil> the cutdown is what - nichrome?
[19:48] <Laurenceb> 10 ohm resistor
[19:48] <SpeedEvil> ah
[19:49] <SpeedEvil> sure the MOSFET has adequate Rds(on) at the gate voltage, at the reduced temps, and the battery ESR is low enough?
[19:49] <Laurenceb> yeah
[19:49] <SpeedEvil> actually - the first would just delay cutdown by a second or two, as it'd warm up;
[19:49] <Laurenceb> theres a few ohms here and there
[19:49] <Laurenceb> probably <2
[19:49] <Laurenceb> yeah I'm firing it for 8 seconds
[19:51] <Laurenceb> how does epilogues and prologues change code execution time?
[19:51] <SpeedEvil> With animated cutscenes?
[19:52] <Laurenceb> what
[19:53] <SpeedEvil> nvm
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[19:56] <SpeedEvil> you're using c++?
[19:57] <Laurenceb> nope just c
[19:57] <SpeedEvil> oh - right.
[19:57] <SpeedEvil> well - for every function, they are going to boost it, taking up a few cycles.
[19:58] <SpeedEvil> Unless stuff happens to be in the right order anyway
[20:01] <SpeedEvil> Modulo cache effects, and multiple execution units, which probably won't be there in your case.
[20:04] <Laurenceb> hmm well I can shrink the code a lot by removing them
[20:04] <Laurenceb> but will it run faster or slower?
[20:04] <SpeedEvil> For microcontrollers, with limited or no cache, in general smaller code is always faster.
[20:05] <Laurenceb> cool
[20:05] <natrium42> Laurenceb, you can make it generate assembly listing and see for yourself :P
[20:06] <SpeedEvil> yeah
[20:06] <SpeedEvil> looking at generated code is great
[20:07] <SpeedEvil> Looking at and understanding is even better
[20:07] <Laurenceb> some chance :P
[20:07] <natrium42> lol
[20:08] <natrium42> also, it only makes sense to spend time optimizing functions which are called often
[20:08] <Laurenceb> unless your bored
[20:08] <SpeedEvil> It can lead you to seeing what looked like a logical choice for a line of code, and emits 20* what you thought it should
[20:08] <SpeedEvil> as a target for reworking
[20:08] <natrium42> or have a PhD to work on
[20:08] <SpeedEvil> natrium42: if you have infinite space
[20:08] Action: natrium42 gets out the whip
[20:09] <SpeedEvil> natrium42: if you're running out of space, you need to optimise it all for space.
[20:09] <SpeedEvil> As to speed/space
[20:09] <SpeedEvil> get your hands on an instruction timing list.
[20:09] <natrium42> yeah
[20:09] <natrium42> but usually it's faster to get a larger chip :P
[20:09] <SpeedEvil> 'Oooh - this micro has a 64 bit MAC instruction'
[20:10] <SpeedEvil> But it takes 73 cycles worst-case.
[20:10] <Laurenceb> the math lib for avr is very fast
[20:10] <SpeedEvil> I mean instructions
[20:10] <Laurenceb> yeah
[20:11] <SpeedEvil> the stm32 has some large MAC instructions that are quite slow
[20:11] <Laurenceb> actually makes it faster than Maxq for anything involving maths
[20:11] <SpeedEvil> They are not slower than doing it by hand - but they aren't 70MHz
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[20:24] <Laurenceb> hi mc-
[20:33] <Laurenceb> cya all
[20:42] <mc-> cya
[20:42] <mc-> natrium42
[20:48] <mc-> I think your antenna doesn't work, because it's interfered by the GPS.
[20:48] <mc-> best to have the GPS on one side, and the antenna on the opposite, with a gnd plane in between
[20:52] <mc-> you can test it by putting the antenna on a bareboard with a bit of coax going to a board with the GPS
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[21:42] <natrium42> mc-, i got it to work
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[22:38] <Laurenceb_> looks armless
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[23:18] <natrium42> h armless :P
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[23:40] Action: Laurenceb yawns
[23:41] <Laurenceb> might go outside for some final testing...
[23:41] <Laurenceb> dont know what people will think... it'll look a bit crazy
[23:41] <Laurenceb> at least its dark
[23:41] <natrium42> is launch this weekend?
[23:42] <Laurenceb> doesnt look like it, too much jet stream
[23:42] <natrium42> :(
[23:42] <natrium42> bbl
[23:42] <Laurenceb> http://www.youtube.com/watch?v=sLVXmsbVwUs
[00:00] --- Sat Mar 14 2009