highaltitude.log.20081016

[00:00] <jcoxon> night all
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[00:16] <G8KHW> night all
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[00:22] <Laurenceb> hmm time for a midnight feast cya
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[00:22] <fuzzylugnuts> Hey
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[00:26] <fuzzylugnuts> +100 to Byonics for their tinytrak 4
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[00:27] <fuzzylugnuts> its a 75$ full kiss tnc that you can stick a display on
[00:41] <SpeedEvil> TNC?
[00:42] <fuzzylugnuts> terminal node controller
[00:42] <fuzzylugnuts> data goes in, radio packet comes out
[00:42] Action: SpeedEvil should know what that means.
[00:42] <SpeedEvil> ah
[00:42] <fuzzylugnuts> it currently does ax.25 but there are plans for PSK
[00:43] <SpeedEvil> Gas turbines - on the order of 45% I think.
[00:43] <SpeedEvil> oops
[00:45] <fuzzylugnuts> http://www.byonics.com/tinytrak4/
[00:45] <fuzzylugnuts> I got 2 of the smt versions and 2 displays
[01:01] <fuzzylugnuts> http://coyotefirecracker.selfip.com/tnc.jpg
[01:03] <Laurenceb> I love the CAUV team photos
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[03:08] <SpeedEvil> http://www.youtube.com/watch?v=eS2rjcVcaqQ
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[07:36] <rjharrison> Morning ed
[07:36] <rjharrison> don't yoy have lectures to get too :)
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[09:49] <Laurenceb> hello
[09:53] <gordonjcp> Laurenceb: morning
[09:53] <gordonjcp> and indeed everyone else
[09:53] <Laurenceb> I just rang up anglia about FRAM
[09:54] <Laurenceb> they dont have the 64KB I2C in stock, so you have to order in quantities of 100 :-/
[10:09] <Laurenceb> I'm off, cya
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[12:53] <SpeedEvil> http://www.youtube.com/watch?v=KmKdA6L_MWk&feature=related Not the way I'd start the engines. (silly R/c)
[12:56] <SpeedEvil> Insane.
[12:56] <SpeedEvil> Bigger and probably higher powered than a cricri
[12:57] <Laurenceb> http://www.selectsolar.co.uk/pics/MPT3.6-150%20(100mA%20at%203.6V).php
[12:59] <SpeedEvil> Awesome - high alpha jet.
[12:59] <SpeedEvil> http://www.youtube.com/watch?v=sFypnPK1dPU&feature=related
[13:00] <Laurenceb> that thing is so big they may as well have put a seat in it
[13:01] <SpeedEvil> For a small person, you could damn near do a prone seat.
[13:03] <SpeedEvil> Damn.
[13:03] <SpeedEvil> I've got some stuff that looks _just_ like those solar cells.
[13:04] <Laurenceb> that jet is insane
[13:04] <SpeedEvil> It is.
[13:04] <SpeedEvil> Beautifully insane.
[13:04] <Laurenceb> hmm you have some thin film cells?
[13:04] <SpeedEvil> If I diddn't have any morals, I'd be putting the stuff up on ebay cheaply.
[13:04] <SpeedEvil> No, it's heating film.
[13:04] <Laurenceb> ah :P
[13:05] <SpeedEvil> I wonder how much thrust vectoring is actually done in that R/C
[13:06] <Laurenceb> its got to have thrust vectoring to pull off some of those manovers ?
[13:06] <SpeedEvil> yes.
[13:06] <Laurenceb> I'd be interested to see the mechanism
[13:06] <SpeedEvil> I mean is it just pitch, or all axis.
[13:06] <SpeedEvil> The real ones look like flowers almost.
[13:06] <Laurenceb> it could adjust the rpm between engines
[13:06] <SpeedEvil> Not real well with turbines.
[13:07] <SpeedEvil> They are quite laggy.
[13:07] <Laurenceb> yeah, they spin so fast
[13:07] <SpeedEvil> I've been contemplating something silly with ground-powered things.
[13:08] <SpeedEvil> http://www.dealextreme.com/details.dx/sku.15230
[13:08] <SpeedEvil> 4-5 of those, powered from the ground, with a cable.
[13:08] <SpeedEvil> 2Kg of mains 5A or twincore cable goes quite far.
[13:09] <Laurenceb> II was thinking of making a mini long duration payload with a lassen iq, one of my radio boards, a solar cell and a lipo
[13:09] <Laurenceb> lol your nuts
[13:11] <Laurenceb> should be <100 grams
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[13:15] <Laurenceb> it'd need some sort of ballast control
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[13:18] <Laurenceb> need to try making something like http://wiki.ukhas.org.uk/_media/ideas:ethanol.png
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[13:29] <edmoore> rjharrison: I had already left!
[13:31] <Laurenceb> hello ed
[13:32] <edmoore> hi
[13:34] <Laurenceb> do you have any of your secret envelopes left over?
[13:34] <edmoore> secret whats?
[13:34] <Laurenceb> oh its not secret anymore
[13:34] <Laurenceb> zero pressure
[13:35] <Laurenceb> I was thinking of making a zp long duration payload - a few hundered grams
[13:51] <edmoore> we won't be in a position where we have spares to give away
[13:51] <edmoore> for at least several months
[13:51] <Laurenceb> k
[13:51] <edmoore> too much going on to have time to make spares
[13:51] <Laurenceb> ah ok
[13:51] <Laurenceb> I thought you might have some prototypes left over
[13:52] <Laurenceb> anyway I need to work out how to make a valve first
[13:57] <edmoore> the envelopes we make aren't designed to take much pressure at all
[13:57] <edmoore> we sacrifice some geometric efficiency for manufacturing ease
[13:57] <Laurenceb> yeah
[13:57] <Laurenceb> I'm just thinking of making a zp
[13:57] <edmoore> you might want a differential pressure sensor
[13:57] <edmoore> oh ok
[13:58] <Laurenceb> the valve is for ballast
[13:59] <edmoore> ok cool
[13:59] <edmoore> bbl
[14:03] <Laurenceb> I'm thinking something like http://cgi.ebay.co.uk/Circular-Disc-Rod-Magnets-Neodymium-10mm-x-10mmA-N42_W0QQitemZ350105386015QQcmdZViewItem?hash=item350105386015&_trkparms=72%3A1346%7C39%3A2%7C66%3A2%7C65%3A12%7C240%3A1318&_trksid=p3286.c0.m14
[14:03] <Laurenceb> resting on an o ring and free to be pulled a few mm up a tube by a coil
[14:05] <Laurenceb> its probably buildable without a lathe....
[14:09] <Laurenceb> I want to try circumnavigation in the polar stratospheric vortex
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[15:05] <SpeedEvil> Fun.
[15:05] <Laurenceb> I might try making as tetroon envelope
[15:05] Action: SpeedEvil ponders failure modes.
[15:06] <SpeedEvil> Alcohol should dissolve any ice which would want to form.
[15:08] <Laurenceb> I'm going to aim for stratospheric flight
[15:08] <Laurenceb> so much easier
[15:11] <Laurenceb> it very easier to make, you just seal off either end of a cylinder
[15:12] <Laurenceb> http://en.wikipedia.org/wiki/Tetrahedron
[15:13] <SpeedEvil> http://en.wikipedia.org/wiki/Great_icosahedron
[15:14] <Laurenceb> erm......
[15:14] <Laurenceb> !math 2+2
[15:15] <Laurenceb> rofl
[15:15] <Laurenceb> zeusbot cant calculate :(
[15:22] <Laurenceb> hmm looks like a 3meter side lenght of 3 meters for the tetroon will work
[15:30] <Laurenceb> ok yeah about 500 gram total mass
[15:30] <Laurenceb> about half of that ethanol
[15:30] <Laurenceb> 3 meter side lenght with a 10um polythene tetroon
[15:32] <Laurenceb> will cruise at around 16.5Km
[15:59] <Laurenceb> which is about enough to reliably stay stratospheric at high latitudes
[15:59] <Laurenceb> http://ams.confex.com/ams/pdfpapers/94102.pdf
[15:59] <SpeedEvil> Use AA batteries as ballast.
[15:59] <Laurenceb> rofl
[15:59] <Laurenceb> actually a good idea
[15:59] Action: SpeedEvil ponders puzzled penguins getting hit by duracells.
[15:59] <Laurenceb> they'd be dead not puzzled
[16:00] <SpeedEvil> True.
[16:00] <Laurenceb> yeah 50 grams/day is more than enough
[16:00] <Laurenceb> to power the payload
[16:00] <SpeedEvil> polythene envelope?
[16:00] <Laurenceb> yeah
[16:01] <Laurenceb> releasing the batteries could be tricky
[16:09] <Laurenceb> http://uk.farnell.com/1606613/semiconductors-integrated-circuits/product.us0?sku=maxim-ds2482s-800&_requestid=475026
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[16:18] <Laurenceb> that paper is really useful
[16:19] <Laurenceb> pity it doesnt seem to have the figures... they recorded the internal supertemperature
[16:19] <Laurenceb> bet you could be some groovy stuff with control loops and filtering based on sun angle, gps ascent rate, and measured supertemperature
[16:20] <Laurenceb> that IC could be used to control a 1wire network
[16:31] <Laurenceb> oh ignore me the figures are at the bottom of the pdf
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[16:52] <Laurenceb> problem is getting a temp sensor that goes below -55
[16:53] <natrium42> hi
[16:53] <SpeedEvil> pt100
[16:53] <natrium42> pt100 to you too
[16:56] <Laurenceb> yeah
[16:56] <Laurenceb> sucks that theres only 2 adc pins brocken out on my radio pcb
[16:57] <Laurenceb> *broken
[16:58] <Laurenceb> http://diydrones.com/profiles/blog/show?id=705844%3ABlogPost%3A44814
[16:58] <Laurenceb> ^ nice
[16:59] <Laurenceb> but I think they've gone down the wrong path with their two uC system
[16:59] <Laurenceb> I'm sure you could fit everything on one uC
[16:59] <SpeedEvil> It does have arguments for it.
[17:00] <SpeedEvil> One does the hard-realtime and bugger all else.
[17:00] <Laurenceb> and one for nav
[17:00] <SpeedEvil> The other just talks to it and does non-critical and UI stuff.
[17:00] <Laurenceb> yeah that was my approach on the first rogallo
[17:00] <Laurenceb> but you can do both on one uC with some flags for controlling data exchange
[17:00] <SpeedEvil> Sure.
[17:01] <Laurenceb> as in my current code
[17:01] <Laurenceb> it is quite large, only about 500 bytes free atm
[17:01] <Laurenceb> but they dont need a kalman filter
[17:01] <SpeedEvil> Of course you could step up and do STM32 or something.
[17:01] <Laurenceb> yeah
[17:02] <SpeedEvil> QFN36, 5 quid or something, 20K RAM, 128K ROM
[17:02] <Laurenceb> their two atmewga and one attiny design sucks to me
[17:02] <Laurenceb> hmm I need to learn ARM
[17:02] <Laurenceb> what compiler do you use?
[17:04] <SpeedEvil> I've not got onto the hardware yet.
[17:04] <SpeedEvil> Err
[17:04] <SpeedEvil> software.
[17:05] <Laurenceb> http://diydrones.com/profiles/blog/show?id=705844%3ABlogPost%3A48246
[17:05] <Laurenceb> ^ looks good nontheless
[17:05] <SpeedEvil> yeah.
[17:06] <natrium42> what drives people to arduino....
[17:06] <natrium42> but looks cool nonetheless
[17:06] <Laurenceb> hehe
[17:06] <SpeedEvil> The whole avoiding talking between micros thing is a powerful argument.
[17:06] <SpeedEvil> As is byzantine faults - where the micros misinterpret what is being said.
[17:06] <Laurenceb> just whack it into gcc ffs
[17:06] <natrium42> but it just seems that people using micros would be the kind of people to use low level things
[17:07] <natrium42> dunno, it doesn't make complete sense to me
[17:07] <Laurenceb> exactly
[17:07] <Laurenceb> thats what I like with uC
[17:07] <SpeedEvil> It depends.
[17:07] <Laurenceb> you can fiddle with the registers
[17:08] <SpeedEvil> For the moment, we're at the point where a 512 byte/20 byte RAM chip is very cheap. And one that you can use C comfortably on might be much more.
[17:08] <SpeedEvil> If you're not at that very bottom end point though, going from something that's a little tight, to something quite roomy isn't that much of a jump.
[17:09] <natrium42> price difference is negligible
[17:09] <natrium42> for us at least
[17:09] <Laurenceb> you can run C on something costing peanuts
[17:09] <SpeedEvil> natrium42: depends on the product.
[17:09] <natrium42> since we are not mass-producing
[17:09] <Laurenceb> yeah
[17:09] <natrium42> $10 vs $20, who cares
[17:09] <Laurenceb> the processor is about 0.05% of the cost
[17:09] <SpeedEvil> natrium42: if you're actually selling it - even low volumes is an issue.
[17:09] <natrium42> yah
[17:09] <SpeedEvil> natrium42: $10 vs $20 = $20-$40 on the sale side at least.
[17:09] <Laurenceb> natrium more like $1 vs $2 for uC
[17:10] <natrium42> i did small runs of devices
[17:10] <natrium42> up to 400 pcs
[17:10] <Laurenceb> yeah, what compiler did you use for 8051?
[17:10] <SpeedEvil> 8051 has been around forever though.
[17:10] <natrium42> sdcc
[17:10] <Laurenceb> ah cool
[17:11] <natrium42> i don't like 8051 isa
[17:11] <SpeedEvil> interestingly a bit ago I found the cheapest micro was 8051 based.
[17:11] <SpeedEvil> on digikey that is.
[17:11] <natrium42> but some of the chips have good features and price point is right
[17:11] <natrium42> so you don't care about isa, sometimes
[17:13] <natrium42> i actually need to get working on a new version
[17:13] <natrium42> people are bugging me
[17:13] <natrium42> i have 100 people in waiting queue already :/
[17:13] <SpeedEvil> wassis?
[17:13] <natrium42> dserial2
[17:17] <Laurenceb> isa?
[17:18] <Laurenceb> can people see this pdf? http://ams.confex.com/ams/pdfpapers/94102.pdf
[17:18] <natrium42> instruction set architecture
[17:18] <natrium42> i can see it
[17:18] <Laurenceb> ah cool
[17:18] <Laurenceb> I'll put it on the wiki then
[17:19] <Laurenceb> very very useful for zp control IMO
[17:19] <SpeedEvil> I can see it.
[17:19] <Laurenceb> pity they dont have more data
[17:19] <Laurenceb> I may email the authors
[17:19] <natrium42> cool
[17:20] <Laurenceb> I cant stop thinking about cool control techniques now
[17:20] <Laurenceb> looks like it may be a good idea to have temp sensors inside and outside of the envelope
[17:21] <Laurenceb> and maybe calculate solar elevation
[17:21] Action: SpeedEvil wonders about a coupled balloon.
[17:21] <SpeedEvil> silver and black.
[17:21] <Laurenceb> thats called an MRI
[17:21] <SpeedEvil> With a couple of tubes, and a fan to drive gas through the black
[17:22] <Laurenceb> things like that never seem to be practical
[17:22] <SpeedEvil> yeah.
[17:22] <Laurenceb> volume/mass ratios
[17:22] <Laurenceb> I looked at a CNES style MIR, but it has to be quite large to work
[17:23] <Laurenceb> and I dont fancy making a 10m diameter envelope
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[18:20] <Laurenceb> speed
[18:20] <Laurenceb> I want to measure delta T between inside and outside the envelope
[18:20] <SpeedEvil> thermocouple'd work.
[18:20] <Laurenceb> yeah
[18:20] <SpeedEvil> Or pt100
[18:21] <SpeedEvil> the thermocouple won't be very linear.
[18:21] <Laurenceb> over temperature of operation or delta T ?
[18:23] <SpeedEvil> delta-t
[18:23] <SpeedEvil> I'm assuming you were meaning simply connecting them in series
[18:24] <Laurenceb> yeah
[18:25] <SpeedEvil> Look at the curve and see if it's linear enough. Or add another channel
[18:28] <Laurenceb> well I want to measure delta T fairly accurately at around -60 to -40 C
[18:28] <Laurenceb> in low pressure air
[18:28] <Laurenceb> I think type K thermocouple
[18:34] <Laurenceb> http://images.picotech.com/thermocoupleslow.gif
[18:34] <Laurenceb> ^ looks pretty linear
[18:45] <Laurenceb> hmm a ADS1112IDGST would be perfect :D
[18:53] <Laurenceb> well time for me to go, cya all
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[20:08] <rjharrison> evening all
[20:09] <rjharrison> Getting all packed up tonight for tomorrow
[20:09] <rjharrison> Well for Saturday launch
[20:18] <natrium42> what time are you launching?
[20:21] <natrium42> rjharrison, ?
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[20:49] <Laurenceb> bah I just missed an icom pcr-1000 on ebay
[20:49] <Laurenceb> by 6 seconds :(
[20:50] <Laurenceb> went for £147
[20:58] <Hiena> Anybody has a plan for a good 5 or 17 element VHF Yagi ?
[20:58] <gordonjcp> yes
[20:58] <gordonjcp> wa5vjb cheap yagi
[20:59] <Hiena> These are PC Yagis. I need for the lower TV band.
[21:01] <gordonjcp> ?
[21:02] <gordonjcp> Hiena: I don't understand that
[21:02] <Hiena> PCB Yagis.
[21:02] <gordonjcp> ?
[21:03] <Hiena> Also the the Cheap Yagi pdf has a designs from 144 Mhz up to 2.4 Ghz.
[21:03] <gordonjcp> yup
[21:03] <gordonjcp> it works
[21:03] <Hiena> I need something between 50Mhz up to 70 Mhz.
[21:04] <gordonjcp> for TV?
[21:04] <gordonjcp> you need a time machine
[21:05] <Hiena> Sigh...For the telemetry, i use small VHF TVband transmitters due the "time machine" effect.
[21:05] <gordonjcp> why not just scale up the 144MHz design?
[21:05] <rjharrison> natrium42: Sorry
[21:05] <rjharrison> Sorting the kids out
[21:05] <rjharrison> 8am BST 7amUTC
[21:06] <gordonjcp> Hiena: VHF TV? 1986 called, they wanted to remind you that VHF TV is long gone
[21:08] <Hiena> gordonjcp, the most tunercard able to receive this band. This band has a better range/power ratio than the UHF band, and NOBODY USE IT, so i'll not disturb anyboby.
[21:09] <rjharrison> Anyone seens ed tonight
[21:09] <Laurenceb> hmm farnell seems to be down
[21:09] <Laurenceb> can anyone get it?
[21:09] <rjharrison> no
[21:09] <rjharrison> it's down
[21:09] <Laurenceb> sucks
[21:09] <Hiena> Not to mention, i have no 1000 bucks to buy a good oscilloscope....
[21:09] <Hiena> Laurenceb, they doing some maintennace.
[21:10] <rjharrison> !w edmoore
[21:10] <rjharrison> !whois edmoore
[21:10] <Hiena> They are down since yesterday.
[21:10] <Laurenceb> god
[21:10] <Laurenceb> didnt edmoore say he was away today?
[21:11] <rjharrison> Possibly is anyone else on here cusf
[21:11] <Hiena> My co-worker doing the purchases, so it must be down since yesterday 10am., because he swearing endlessly since then.
[21:11] <rjharrison> I was trying to find out their anticipated launch time
[21:12] <Laurenceb> Hiena: I was on it earlier
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[21:31] <Laurenceb> ok... I've been thinking about a long duration tetroon...
[21:31] <Laurenceb> you could use two 4x5m 9.6um polythene sheets from b&q
[21:32] <Laurenceb> to make a 4.6 meter side lenght tetroon, 11.7m^3 that would cruise at 22Km for 5 days
[21:32] <Laurenceb> about 600grams dry weight, 1kg with ethanol ballast
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[21:48] <SpeedEvil> He?
[21:49] <Laurenceb> yes
[21:50] Action: SpeedEvil plans an Al/CH4 balloon soon.
[21:50] <SpeedEvil> I've got some canned GPS sondes that I can use.
[22:05] <Laurenceb> I dont think its going to work
[22:06] <Laurenceb> for the ballast valve I'm thinking one of these o rings http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=5279762
[22:06] <Laurenceb> at the bottom of some 3/16'' pvc tube
[22:06] <Laurenceb> with a neodynium magnet on top of it
[22:07] <Laurenceb> and a small piece of plastic sheet underneath
[22:07] <Laurenceb> then theres a large coil of thin magnet wire above, wrapped around the pvc tube
[22:07] <SpeedEvil> what's the o-ring?
[22:08] <Laurenceb> then one of these http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=5279762 epoxied into the top of the tube
[22:08] <Laurenceb> the magnet rests on the o ring normally
[22:08] <Laurenceb> blocking the flow
[22:09] <Laurenceb> a current to the coil lifts up the magnet
[22:09] <SpeedEvil> How do you stop the magnet fliippng?
[22:09] <SpeedEvil> check compatibility.
[22:10] <SpeedEvil> I'm unsure nitrile+ethanol works
[22:10] <Laurenceb> diameter is about 1 to 0.5mm less than the tube ID
[22:10] <Laurenceb> no silicone
[22:10] <SpeedEvil> ah
[22:10] <Laurenceb> nitrile doesnt like low t
[22:10] <SpeedEvil> you linked to nitrile
[22:10] <SpeedEvil> As long as teh magnet has smooth corners.
[22:10] <SpeedEvil> And can't get hung up on the tube by sharp ones
[22:11] <Laurenceb> no, thats a silicone one
[22:11] <SpeedEvil> The Nitrile 'O' rings are available in both Metric and Imperial sizes. Imperial sizes are to BS1806, Metric sizes are to BS4518.
[22:11] <SpeedEvil> ah
[22:11] <SpeedEvil> misread
[22:11] <Laurenceb> you can pick up small cylindrical ones
[22:11] <Laurenceb> on ebay
[22:11] <SpeedEvil> or just use a few 8mm*1mm or whatever in series.
[22:12] <SpeedEvil> got a couple of hundred of those from DX.
[22:12] <SpeedEvil> SSo handy.
[22:13] <Laurenceb> hopefully I can wind a coil that will go straight onto an IO pin
[22:13] <SpeedEvil> Ummm.
[22:13] <SpeedEvil> That's probably a bit optimistic.
[22:13] <Laurenceb> you can draw 40ma
[22:13] <SpeedEvil> To lift that large a magnet
[22:15] <SpeedEvil> I dunno.
[22:15] <Laurenceb> time to do the maths
[22:15] <SpeedEvil> Indeed.
[22:15] <SpeedEvil> Or physical tests.
[22:15] <SpeedEvil> Don't forget hydrostatic pressure.
[22:16] <SpeedEvil> alcostatic pressure :)
[22:22] <SpeedEvil> /win go 4
[22:23] <Laurenceb> well its hard to guesstimate
[22:23] <SpeedEvil> What is?
[22:23] <Laurenceb> field at the surface is ~1.4T
[22:24] <SpeedEvil> Just make one.
[22:24] <SpeedEvil> Copper wire, 'square' coil, ...
[22:24] <Laurenceb> but its how it behaves from there
[22:25] <Laurenceb> a few hundered turns should work
[22:25] <Laurenceb> need some field sim software
[22:25] <SpeedEvil> You need a magnet and some wire.
[22:26] <SpeedEvil> You'd have had it done by now.
[22:26] <Laurenceb> lol
[22:26] <Laurenceb> its going to work
[22:26] <SpeedEvil> Sure - at 5v/40mA is the question.
[22:27] <Laurenceb> thats what I mean
[22:27] <Laurenceb> 0.04*1.4 is big
[22:29] <Laurenceb> well actally 0.01m*0.04amps*1.4T is a better guess
[22:29] <Laurenceb> we lose a lot of the field
[22:30] <SpeedEvil> yeah
[22:30] <Laurenceb> about 10^-4 N per turn
[22:30] <Laurenceb> might require up to 1000 turns
[22:30] <SpeedEvil> over 9000 turns!
[22:31] <Laurenceb> not that many
[22:31] <SpeedEvil> what's the column of alcohol?
[22:31] <Laurenceb> ~10cm
[22:31] <SpeedEvil> You should try to get some sponsorship.
[22:31] <SpeedEvil> Smirnoff.
[22:31] <Laurenceb> haha
[22:41] <Laurenceb> but its probably easier to stick a fet on it
[22:47] <Laurenceb> http://www.youtube.com/watch?v=s1xS-ssfTM8
[22:48] <natrium42> lol
[22:49] <natrium42> he messed up his TV, didn't he?
[22:50] <rjharrison> wyoming's not playing ball
[22:52] <natrium42> +oon
[22:59] <Laurenceb> aha perfect http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=6424323
[23:00] <Laurenceb> I could put one of those below the valve and use it as a droplet detector
[23:01] <Laurenceb> then you can calculate the total volume of dropped ballast
[23:04] <SpeedEvil> Time it.
[23:04] <Laurenceb> nah
[23:04] <Laurenceb> you dont know its working properly
[23:04] <SpeedEvil> What can you do if it's not.
[23:05] <SpeedEvil> Don't detect what you can't fix.
[23:05] <Laurenceb> droplets are very predictable volume if the flow rate is low enough for them to form
[23:05] <SpeedEvil> Wellllll...
[23:06] <SpeedEvil> I don't see a benefit over 'trigger solenoid for 10% of the time it took to drain on the ground if averaged over the last 6 hours altitude is under x and no drop has been made in 8 hours.'
[23:06] <SpeedEvil> For example.
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[23:11] <natrium42> hi rocketboy
[23:14] <jcoxon> hey all
[23:15] <natrium42> 'lo jcoxon
[23:16] <jcoxon> hey na
[23:16] <jcoxon> natrium42,
[23:16] <jcoxon> you around for the sat launches?
[23:17] <natrium42> yep, for sure
[23:17] <jcoxon> cool cool
[23:17] <natrium42> your beacon flies with rjharrison's payload?
[23:17] <jcoxon> i'll be tracking as much as i can
[23:17] <jcoxon> i'm not flying
[23:18] <natrium42> aah, ok
[23:18] <jcoxon> tis rjharrison's payload (CW beacon)
[23:18] <jcoxon> and Nova 9 (rtty)
[23:18] <natrium42> aah, nice
[23:18] <natrium42> both launched at the same time?
[23:18] <jcoxon> no rjharrison first then nova 9
[23:19] <jcoxon> nova 9 is being filmed by a tv channel
[23:21] <natrium42> awesome stuff :)
[23:21] <natrium42> looking forward to the launches
[23:21] <jcoxon> i'm going to track from london
[23:22] <jcoxon> instead of paying costs to go up to cambridge i'm going to buy a new 5/8th antenna
[23:22] <jcoxon> should massively improve the reception
[23:22] <natrium42> is your antenna inside the house?
[23:22] <natrium42> would it improve significantly if you put it on the roof?
[23:23] <jcoxon> it wasn't for the last flights
[23:23] <gordonjcp> jcoxon: which band do you want it for?
[23:23] <jcoxon> but this time i'm going to put it out the window on a tube to make it a bit higher
[23:23] <jcoxon> 70cm
[23:23] <gordonjcp> jcoxon: hmm
[23:24] <gordonjcp> jcoxon: build one!
[23:24] <jcoxon> i've got a moxon rectangle already
[23:24] <jcoxon> will try that
[23:24] <gordonjcp> ok
[23:24] Action: natrium42 is waiting for 50 ft cable to arrive for HF antenna
[23:24] <gordonjcp> what antennas do you have at the moment?
[23:24] <jcoxon> ummm i have a whip and a moxon
[23:24] <gordonjcp> 'cos remember a rubber duck is about -9dB
[23:24] <gordonjcp> -6dB at best!
[23:25] <jcoxon> the moxon is pretty good
[23:25] <jcoxon> will be a good test
[23:26] <jcoxon> but i hope to get a keep the data flowing
[23:27] <jcoxon> bbl
[23:28] <rjharrison> hi
[23:32] <rjharrison> Bloody wind is picking up
[23:33] <natrium42> that hurricane turned north-east
[23:33] <natrium42> maybe it's influencing the winds?
[23:33] <rjharrison> :) I'm running a quick track on wyoming
[23:35] <rjharrison> If I launched now from 53.655405 -1.670579 I would land in canbridge
[23:35] <rjharrison> BTW Thats home
[23:35] <rjharrison> cambridge even
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[23:46] <natrium42> haha
[23:46] <natrium42> that's what i did once: launched 100km from home, landed home
[23:49] <natrium42> brb, ubuntu -> vista
[23:49] natrium42 (n=alexei@CPE000625d867e2-CM0014045885be.cpe.net.cable.rogers.com) left irc:
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[00:00] --- Fri Oct 17 2008