highaltitude.log.20090114

[00:25] <Laurenceb> any maths gurus?
[00:25] <Laurenceb> I have R=1/2.55*v
[00:26] <Laurenceb> if there are gaussian errors in v with covariance b, will the covariance in R be (1/(2.55*v^2))*b ?
[00:30] Action: SpeedEvil was right with you up to the word gaussian.
[00:30] <SpeedEvil> :)
[00:31] Action: SpeedEvil points at ##math?
[00:41] <Laurenceb> normal distribution
[00:43] <fergusnoble> any hams online?
[00:44] <fergusnoble> how much power should you need to get across 2 miles of fairly flat suburbia on 70cm ssb?
[00:45] <M0TEK> #hamradio
[00:47] <Laurenceb> fergusnobel: I got about that with 10mw and 300 baud rtty
[00:47] <Laurenceb> and 50dB attenuation IIRC
[00:47] <fergusnoble> really? thats good
[00:48] <Laurenceb> Rocketboys spreadsheet on the wiki told we I was missing 6dB somewhere
[00:48] <fergusnoble> me and ed are struggling and ive got 1w tx and hes got 35w
[00:48] <Laurenceb> but there was a steel framed building in the way
[00:48] <fergusnoble> this is not LOS
[00:48] <Laurenceb> same for my test, there was a few streets, a park and a four story steel building
[00:49] <Laurenceb> we had 1/4 wave ants on each end
[00:49] <Laurenceb> and an icom pcr-1000
[00:50] <Laurenceb> total distance was about 1.5 miles
[00:56] <Laurenceb> fergus: do you have decent antenna?
[00:58] <fergusnoble> just a whip
[00:58] <fergusnoble> didnt bring the yagi up
[01:00] <Laurenceb> hmm should work
[01:00] <Laurenceb> are there metal gutters?
[01:01] <Laurenceb> and/or downpipes
[01:06] <fergusnoble> yeah
[01:06] <fergusnoble> old building full of metal
[01:07] <fergusnoble> psk31 is working though
[01:09] <Laurenceb> better than a new building full of extratherm
[01:10] <Laurenceb> and low e glazing units
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[01:40] <Laurenceb> woot
[01:40] <natrium42> ?
[01:40] Action: Laurenceb has optimised descent planning working]
[01:41] <Laurenceb> well its stopped exploding at least
[01:41] <natrium42> haha, nice
[01:41] <M0TEK> fergusnoble and i have just been talking to each other in DominoEX 8 across cambridge
[01:41] <Laurenceb> and the results seem sensible - I'm testing it with kml off the wiki
[01:41] <natrium42> M0TEK: nice
[01:41] <fergusnoble> its really cool
[01:41] <natrium42> now try to reach me in canada :P
[01:42] <Laurenceb> groovy
[01:42] <fergusnoble> our first few overs
[01:42] <Laurenceb> any idea why it wasnt working well with ssb?
[01:42] <M0TEK> am impressed. it's quite fast
[01:42] <M0TEK> i'll keep investigating at my end
[01:42] <M0TEK> there is such a mine of settings on this thing
[01:42] <Laurenceb> when my icom arrives I can join in
[01:42] <M0TEK> could be one stray one somewhere
[01:42] <fergusnoble> yeah, can try the yagi soon
[01:42] <Laurenceb> need to get a license so I can transmit
[01:42] <fergusnoble> Laurenceb: do it, its fun
[01:43] <M0TEK> Laurenceb: yeah you really do
[01:43] <M0TEK> it's pretty easy too
[01:43] <M0TEK> and TXing is fun
[01:43] <Laurenceb> great :P
[01:43] <Laurenceb> I got an icom on ebay earlier - £197
[01:43] <M0TEK> which model?
[01:43] <Laurenceb> pcr-1000
[01:44] <M0TEK> pc controlled?
[01:44] <Laurenceb> yes
[01:44] <M0TEK> that looks quite cool
[01:44] <Laurenceb> I'm going to add AA batteries
[01:44] <Laurenceb> I've seen it done
[01:45] <Laurenceb> you can setup fldigi to autotune the rtty
[01:45] <M0TEK> yes - it was tracking a little just now on some of the other modes too
[01:45] <M0TEK> right, bed time
[01:46] <Laurenceb> cya
[01:46] <M0TEK> fergusnoble: 73s
[01:46] <fergusnoble> goodnight
[01:46] <Laurenceb> gnunight
[01:46] <M0TEK> is that a special open source night?
[01:46] <natrium42> lol
[01:46] <Laurenceb> yes
[01:47] <natrium42> it's GNU/night, damn it
[01:47] Action: Laurenceb runs from stallman
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[01:48] <natrium42> :D
[01:49] <natrium42> if only i had shoes
[01:49] <Laurenceb> wasnt MOTEX some mayan god?
[01:49] <Laurenceb> *MOTEK
[01:50] <natrium42> !wiki motek
[01:50] <natrium42> hmm
[01:51] <Laurenceb> oh... my ...god
[01:51] <Laurenceb> isnt MOTEK the owl at bohemian grove?
[01:54] <Laurenceb> oh dear
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[01:57] Action: Laurenceb watches the Louis Theroux documentary
[01:57] <Laurenceb> no I think they chant MOLEK
[01:57] <Laurenceb> maybe edmoore heard it wrong
[02:42] <Laurenceb> http://wiki.ukhas.org.uk/code:parafoil_tsip?do=diff
[02:42] <Laurenceb> think thats sorted now :P
[02:43] <Laurenceb> it tracks the drag coefficient with an extended kalman filter running at 1Hz, and uses that value together with recorded winds from the ascent to plan an optimal route
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[09:45] <edmoore> morning all
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[11:56] <edmoore> fergusnoble: my irc chat with you says 'fergusnoble is now available'
[11:56] <edmoore> fancy going on a date tonight?
[11:57] <fergusnoble> how does it know?!
[11:57] <fergusnoble> i just brought up the irc window
[11:57] <edmoore> python module probably
[11:57] <edmoore> import Paranoid
[11:57] <fergusnoble> what kind of date?
[11:58] <edmoore> dinner for two?
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[11:58] <edmoore> cinema?
[11:58] <fergusnoble> oh i see, i thought you meant something geeky, not romantic
[11:58] <fergusnoble> you can do better then the cinema
[11:58] <edmoore> also ottoyh do you know they best way of simultaneous ptt and audio squirting?
[11:59] <fergusnoble> nope?
[11:59] <edmoore> i was wondering if there was some standard where one stereo channel is ptt and t'other is audio
[11:59] <edmoore> actually i should just rtfm
[11:59] <fergusnoble> that would be sensible
[11:59] <edmoore> don't want a TNC, that's fo sho
[11:59] <fergusnoble> can't you PTT using the digital control on your radio?
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[12:00] <edmoore> sure but i'm talking about just a cable from eeepc to radio
[12:00] <edmoore> with minimum hardware
[12:00] <fergusnoble> hmm, dunno
[12:00] <edmoore> will have a look
[12:08] <fergusnoble> http://wa8lmf.net/ham/tonekeyer.htm
[12:08] <fergusnoble> presses the ptt when it hears audio input
[12:10] <edmoore> looks like a good solution
[12:25] <fergusnoble> looks like most transmitters have this functionality built in
[12:27] <edmoore> don't want it to accidently transmit me watching youtube vids :D
[12:34] <fergusnoble> edmoore: do you get a strong carrier on 434.172?
[12:35] <edmoore> fergusnoble: there's something there yeah
[12:38] <edmoore> fergusnoble: websdr
[12:38] <edmoore> pictures
[12:39] <edmoore> 'HELLO' just went up the waterfall on 7047
[12:40] <fergusnoble> last night i managed to decode some psk31 from websdr
[12:40] <edmoore> yeah there's lots of interesting stuff
[12:41] <edmoore> i couldget get any of the mfsk though
[12:42] <edmoore> bbl
[12:58] <gordonjcp> fergusnoble: I'm on psk31 on 7037~ just now
[12:58] <fergusnoble> 1 sec
[13:00] <fergusnoble> whats your call?
[13:00] <gordonjcp> MM3YEQ
[13:00] <fergusnoble> copying you
[13:00] <fergusnoble> neat
[13:00] <gordonjcp> sweet
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[13:00] <gordonjcp> and a reply!
[13:01] <fergusnoble> hallam:
[13:01] <fergusnoble> hello
[13:01] <gordonjcp> fergusnoble: you getting that?
[13:01] <fergusnoble> gordonjcp: clear as the day
[13:02] <fergusnoble> the reply is quite feint
[13:02] <gordonjcp> yeah, he's in France
[13:02] <gordonjcp> so possibly too far for groundwave, not far enough for skywave
[13:03] <hallam> Hi Fergus
[13:03] <hallam> what are you up to?
[13:04] <hallam> listening to that webSDR thing?
[13:04] <fergusnoble> decoding psk31 off websdr sent by gordonjcp
[13:04] <hallam> cool
[13:04] <hallam> shouldn't you be taking your exam?
[13:04] <fergusnoble> its at 3
[13:04] <hallam> CUWS Martin suggests that your radio licence results may have been sent to your home address
[13:05] <fergusnoble> ok, ill phone the house
[13:06] <gordonjcp> oooh
[13:06] <gordonjcp> fergusnoble: which exam?
[13:07] <fergusnoble> just a progress test for uni
[13:07] <fergusnoble> nothing too scary
[13:07] <gordonjcp> no, the radio licence one
[13:08] <fergusnoble> full
[13:08] <gordonjcp> cool
[13:08] <fergusnoble> yeah, if i pass
[13:08] <gordonjcp> at the risk of sounding like Top Gear, "How hard can it be?"
[13:08] <fergusnoble> it didnt go amazingly well
[13:09] <fergusnoble> had a lab report in the same day as the exam so didnt get much chance to learn the stuff
[13:09] <hallam> we all started learning for it about 1 hour beforehand, except Fergus who had 30 mins
[13:09] <gordonjcp> ach, it's all common sense
[13:09] <gordonjcp> I'm doing my intermediate next month, in the next batch of exams
[13:10] <hallam> full is a bit trickier than the first two :P I'd recommend at least 2 hours worth of studying to be comfortable
[13:10] <fergusnoble> cool
[13:11] <fergusnoble> psk31 is so much better than rtty for weak signals
[13:11] <gordonjcp> yeah
[13:11] <gordonjcp> I was decoding a signal in gMFSK
[13:11] <gordonjcp> so weak it looked like a smear on the glass
[13:11] <fergusnoble> shame the transmitter on the balloon cant really do it
[13:11] <gordonjcp> I had a QSO with the station
[13:11] <gordonjcp> and then I realised it *was* a smear on the glass
[13:12] <fergusnoble> hehe
[13:12] <hallam> fergusnoble, we could always build a transmitter that could do PSK
[13:13] <fergusnoble> ok, it got sent to my home address
[13:14] <fergusnoble> i passed
[13:14] <fergusnoble> :)
[13:14] <hallam> woo!
[13:15] <gordonjcp> fergusnoble: yay!
[13:15] <fergusnoble> what does the "pse k" mean at the end of people calling CQ?
[13:15] <gordonjcp> fergusnoble: "please reply" I think
[13:16] <fergusnoble> cool
[13:16] <gordonjcp> it's set in the "CQ" macro in gMFSK
[13:17] <gordonjcp> wonder how hard it is to do a scrolly sdr message
[13:20] <hallam> fergusnoble: Did you read this? http://www.geotate.com/files/Geotate_CP_White_Paper.pdf it's pretty cool. Maybe we could go and see him, he's in London IIRC
[13:22] <fergusnoble> hallam: not seen that thanks
[13:23] <fergusnoble> hallam: did you see that SiGe do a chip with 2 antenna inputs
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[13:28] <gordonjcp> hah, oops
[13:28] <gordonjcp> I just transmitted some "your battery is going flat" and "your charger is plugged in" beeps, oops
[13:28] <gordonjcp> maybe TX switching with VOX isn't the best idea
[13:34] <gordonjcp> fergusnoble: ping?
[13:35] <fergusnoble> hello
[13:35] <gordonjcp> fergusnoble: which modes can you decode?
[13:36] <fergusnoble> have fldigi, so most digital modes i think
[13:36] <hallam> fergusnoble, no I didn't see that, were you thinking of attitude determination or something?
[13:37] <gordonjcp> fergusnoble: fancy trying MT63?
[13:37] <fergusnoble> hallam: no, was thinking if we need to come down nose first for recovery we can have a second antenna in the tail
[13:37] <fergusnoble> yeah, sure
[13:38] <gordonjcp> k
[13:38] <fergusnoble> gordonjcp: i have the option of -500, -1000 or -2000
[13:38] <gordonjcp> 7040, it'll start 500Hz above
[13:38] <hallam> makes sense, though I was thinking of just using a chip antenna with a window in the side of the rocket tube
[13:38] <gordonjcp> ... or below
[13:38] <gordonjcp> that was me
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[13:39] <fergusnoble> didnt catch it
[13:39] <fergusnoble> try again?
[13:39] <hallam> hi Tigga
[13:39] <gordonjcp> there I am again
[13:39] <gordonjcp> big pink stripe just over 7040
[13:40] <fergusnoble> got it but no copy
[13:40] <fergusnoble> IS IT MT63-1000?
[13:41] <gordonjcp> yes
[13:41] <gordonjcp> interleave 64
[13:41] <gordonjcp> ready/
[13:41] <gordonjcp> ?
[13:41] <fergusnoble> ok
[13:42] <fergusnoble> it doesnt seem to like it
[13:43] <fergusnoble> try ?
[13:43] <fergusnoble> try again?
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[13:44] <gordonjcp> fergusnoble: fail?
[13:44] <fergusnoble> yeah, fail
[13:44] <gordonjcp> oh well
[13:44] <gordonjcp> what about psk63?
[13:44] <fergusnoble> maybe try a quieter spot?
[13:45] <gordonjcp> I'm just a fraction above 7040 on psk63
[13:45] <fergusnoble> got you on psk63
[13:45] <gordonjcp> hmm
[13:45] <gordonjcp> MFSK8?
[13:45] <fergusnoble> ok
[13:46] <gordonjcp> man, that took ages
[13:47] <fergusnoble> was tuned in i think but didnt get it
[13:47] <fergusnoble> dominoex is fun
[13:47] <gordonjcp> don't think I have that
[13:48] <fergusnoble> what else do you have?
[13:48] <gordonjcp> ah well, the PSK modes work and work well
[13:48] <gordonjcp> olivia?
[13:48] <fergusnoble> ok, which one?
[13:49] <fergusnoble> 8/500?
[13:49] <gordonjcp> ok
[13:50] <fergusnoble> got it
[13:50] <fergusnoble> try again, only got the tail end
[13:50] <fergusnoble> neat
[13:51] <fergusnoble> perfect copy
[13:51] <fergusnoble> ok, i should probably revise for this exam
[13:52] <fergusnoble> thanks though gordonjcp, was fun
[13:52] <gordonjcp> thanks for the dual-mode QSO ;-)
[13:52] <gordonjcp> have you got any HF kit?
[13:52] <fergusnoble> no, just 70cm
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[13:53] <fergusnoble> dont think that would make it up to glasgow from here :)
[13:53] <gordonjcp> heh
[13:53] <gordonjcp> IRLP?
[13:53] <gordonjcp> where are you anyway?
[13:53] <fergusnoble> edmoore has HF kit though, will pester him to sling up an antenna
[13:53] <gordonjcp> I've heard people in the far south of England on 7
[13:53] <fergusnoble> Cambridge
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[14:20] <edmoore> fergusnoble , gordonjcp yo
[14:20] <edmoore> sounds like you two are having fun :)
[14:20] Nick change: edmoore -> M0TEK
[14:21] <fergusnoble> M0TEK: want to have a play with the repeater?
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[14:21] <fergusnoble> try tuning into 433.200
[14:21] <M0TEK> have got tutor meeting at 2.30 then DoS meeting at 3
[14:21] <M0TEK> free after that though
[14:22] <fergusnoble> i have an exam 3-6
[14:22] <M0TEK> progress?
[14:22] <fergusnoble> yeah
[14:22] <fergusnoble> btw, i passed the radio exam
[14:23] <M0TEK> get a callsign!
[14:23] <fergusnoble> will do in a bit
[14:23] <M0TEK> M0FOZ
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[14:25] <fergusnoble> why FOZ?
[14:25] <M0TEK> M0FOZ
[14:25] <hallam> mofo's
[14:25] <M0TEK> hams in da hood
[14:25] <hallam> M0OSE would be good, but I'm sure it's gone
[14:26] <M0TEK> DX ma bitch up
[14:26] <M0TEK> suggest QSL to channel aaaaiiigght
[14:26] <M0TEK> etc.
[14:27] <M0TEK> ok tutor meeting
[14:27] <M0TEK> bbiab
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[15:36] <M0TEK> hallam: just emailed
[15:36] <M0TEK> didn't spot you were here
[15:39] <rharrison> all this MO stuff
[15:41] <hallam> jealous? :P
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[15:59] <M0TEK> rharrison: if you can't beat 'em
[15:59] <M0TEK> hallam: yes, can synthesise 70cm with a 400MSPS chip
[15:59] <rharrison> hehe
[15:59] <SpeedEvil> with filters
[16:00] <rharrison> I'll be there just not this week
[16:00] <M0TEK> SpeedEvil: yes
[16:00] <rharrison> 2E0 on 31st
[16:00] <M0TEK> bandpass one of the sampling images
[16:00] <rharrison> M0 in March/April
[16:01] <M0TEK> so say you PLL up the 19.2mhz crystal to 364.8Mhz (i.e. multiply by 19)
[16:01] <M0TEK> then you ask that DDS to generate a tone at 80Mhz
[16:01] <M0TEK> you'll get your 80mhz signal, but being a sampling system, you'll also get images at 364.8 + 80 and 364.8 - 80
[16:02] <M0TEK> 364.8+ 80 is conveniently 70cm
[16:02] <M0TEK> so you BPF and amplify that image
[16:02] <M0TEK> it's about 14dB lower than the main signal but that's not really a big deal if you're amplifying anyway. it's there
[16:02] <M0TEK> it's lower dB as it's on the first lobe on a sinc(x) pulse, if you follow my reasoning
[16:03] <M0TEK> I *think* this is the case anyway
[16:03] <M0TEK> my DoS is a signals specialist and I will get him to sanity check it for me
[16:03] <SpeedEvil> I was actually meaning not that.
[16:04] <M0TEK> I think it holds water though doesn't it?
[16:04] <M0TEK> and it makes us frequency agile
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[16:04] <M0TEK> and you can do FSK and BPSK on it
[16:04] <SpeedEvil> For example, take a 400MHz arbitrary waveform generator, you can use it to generate any 433MHz signal that's of a bandwidth of under a few MHz with just a filter at 433MHz
[16:05] <M0TEK> SpeedEvil: sure - but I don't think our dds is arbitrary, if I follow your meaning
[16:05] <SpeedEvil> yeah.
[16:05] <M0TEK> are you saying that if you, say, gen a 400mhz triangle wave, you've obviously got harmonics above 400mhz?
[16:05] <SpeedEvil> not quite.
[16:06] <SpeedEvil> Umm
[16:06] <SpeedEvil> If you have a filter with near-infinite Q, and poke it once a second with the right voltage at precisely the right time, you can get it to ring controllably.
[16:06] <M0TEK> ah sure, i follow you
[16:07] <SpeedEvil> If you're close to the resonant frequency, then the Q needed gets rather modest.
[16:07] <hallam> just how precise is the precisely-right-time?
[16:08] <SpeedEvil> hallam: it depends on 'stuff'.
[16:08] <M0TEK> well this particular DDS has a 32-bit freq setting register
[16:08] <SpeedEvil> hallam: the filter transforms the discontinuous input signal into a continuous desired output signal.
[16:09] <M0TEK> so by my maths that gives us resolution to set the freq of <0.1Hz
[16:09] <SpeedEvil> hallam: however, timing jitter, and voltage errors will come out of the filter as a signal with jitter or undesired noise
[16:09] <SpeedEvil> not: check that
[16:09] <SpeedEvil> M0TEK: in some cases, it can drop dramatically in frequency resolution at some points in the range.
[16:09] <M0TEK> sure, that's way probably a simplificatiion
[16:10] <M0TEK> but it's way way ay beyond our needs
[16:10] Action: SpeedEvil really wishes common DDSs had PPS inputs.
[16:10] <SpeedEvil> Which would snap the timing register and let you read it out over i2c.
[16:10] <M0TEK> SpeedEvil: well as discussed - you can stick a micro in the loop and get freq feedback using pps
[16:10] <SpeedEvil> So you could do _real_ accuracy with GPS.
[16:10] <SpeedEvil> yeah.
[16:10] <SpeedEvil> icky.
[16:10] <M0TEK> but sure, i grant you that 'built in' would be nice
[16:10] <SpeedEvil> As you need lots of external stuff.
[16:14] <M0TEK> SpeedEvil: if you have an FPGA spare, can build some hardware correlators and get accurate 1khz pulses. That'd be nice.
[16:15] <SpeedEvil> FPGA is cheating!
[16:15] <SpeedEvil> It's only fun if you can do it under a fiver :)
[16:15] <M0TEK> touché¡
[16:15] <M0TEK> !
[16:15] <M0TEK> wow funky
[16:15] <M0TEK> ¡!¡!¡!¡!
[16:15] Action: SpeedEvil notes TI has an interesting 32 bit counter chip. (readable out as bytes)
[16:16] <SpeedEvil> TTL
[16:16] <SpeedEvil> but not annoyingly very high freq output.
[16:16] <M0TEK> oh nic
[16:16] <M0TEK> e
[16:16] Action: SpeedEvil was looking at it for a laser ranger.
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[16:16] <SpeedEvil> Only 2-3 quid IIRC look in the logic selector
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[16:21] Nick change: mib_c2fhga -> Laurenceb
[16:26] <M0TEK> hallam: re email, basically yes
[16:26] <M0TEK> am out this saturday and sunday, annoyingly
[16:26] <M0TEK> what time is it due to start?
[16:29] <hallam> 12
[16:29] <hallam> it's only weld-o-tron faff really
[16:29] <hallam> it's the inflation that will be really interesting
[16:33] <M0TEK> yeah
[16:34] <M0TEK> if the freq image idea is a good'n then I will throw together an experimental radio PCB at the same time as the operational one
[16:34] <SpeedEvil> You really should put a decent filter on it though.
[16:34] <SpeedEvil> Otherwise you may annoy people.
[16:34] <M0TEK> of course
[16:36] <M0TEK> that's fun though, not a chore
[16:36] <M0TEK> thought I'd quite like to have BPF for several amateur bands
[16:37] <Laurenceb> if your using a radiometrix its fine
[16:37] <M0TEK> 0-20mhz, 2m, 70cm say. I think I'm breaking the rules of analog electronics though
[16:37] <SpeedEvil> cheap DDS that'd go to a few hundred meg'd be nice.
[16:37] <M0TEK> Laurenceb: am not
[16:37] <Laurenceb> SpeedEvil: AD
[16:37] <Laurenceb> MoTEK: homebrew Tx ?
[16:38] Action: SpeedEvil points Laurenceb at the first word.
[16:38] <Laurenceb> :P
[16:38] <M0TEK> Laurenceb: yes
[16:38] <SpeedEvil> the cheap ones do 20MHz or so.
[16:38] <SpeedEvil> Which is nice, but not really up there.
[16:38] <M0TEK> ad9954
[16:38] <M0TEK> £13
[16:39] <M0TEK> 400Msps
[16:39] <Laurenceb> I'm designing my usb stick atm
[16:39] <Laurenceb> going to use PCB for the board - 4 layer
[16:39] <Laurenceb> rather than eagle
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[16:40] <Laurenceb> I'm wondering if I should make it GPL or not
[16:40] <hallam> What does your usb stick do?
[16:40] <Laurenceb> exists in my mind ;P
[16:41] <Laurenceb> I'm just designing the pcb atm
[16:41] <Laurenceb> its a usb SDR stick
[16:41] Action: hallam gets food
[16:41] Nick change: hallam -> hallam|food
[16:43] <Laurenceb> hopefully a few 100MHz to a few Ghz, 25Mhz bandwidth with 8 bit ADC
[16:43] <Laurenceb> annoyingly its not possible to get icom like performance with a single frontend
[16:43] <Laurenceb> so I'll just have to have a few different sticks to span ~DC to ~2.5Ghz
[16:43] <SpeedEvil> External frontends.
[16:44] <Laurenceb> nah too cumbersome
[16:44] <Laurenceb> it wouldnt end up being much cheaper
[16:45] <Laurenceb> you have to swap out the LNA, VCO, PLL and mixer
[16:45] <SpeedEvil> you found that cheap AD mixer?
[16:45] <Laurenceb> whic is most of the hardware
[16:45] <SpeedEvil> 2GHz 4 quadrant?
[16:45] <Laurenceb> yeah, everything ia from AD
[16:46] <SpeedEvil> what'r you doing to get the data onto the PC?
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[16:46] <Laurenceb> apart from the cypress usb uC with FIFO buffer and 16 bit GPIO
[16:46] <Laurenceb> whci gets it on the PC :P
[16:47] <M0TEK> those chips are everywhere
[16:47] <M0TEK> seem to have found a good niche
[16:47] <Laurenceb> CY7C68015A QFN56 or similar
[16:47] <Laurenceb> only 8mm square
[16:49] <Laurenceb> I think the entire pcb can be made to fit in 15x50mm - so standard usb stick sized
[16:50] <Laurenceb> USB socket in one end, SMA in the other
[16:50] <M0TEK> so a usb-stick SDR?
[16:50] <Laurenceb> yep
[16:50] <M0TEK> oh you said that
[16:50] <M0TEK> sorry
[16:50] <M0TEK> full synthesis?
[16:51] <SpeedEvil> interesting would be onboard RAM.
[16:51] <SpeedEvil> to grab a megabyte or two of sample for later analysis.
[16:51] <Laurenceb> RX only
[16:51] <SpeedEvil> But probably more expensive.
[16:51] <Laurenceb> SpeedEvil: yeah I'm reading the datasheet for the cypress
[16:51] <M0TEK> Laurenceb: RX only - but full sampling or with an RF front end to IF?
[16:51] <Laurenceb> 96MB/sec is possible for birsts
[16:52] <M0TEK> Laurenceb: you'll be lucky :P
[16:52] <Laurenceb> if you have enough ram to store it
[16:52] <Laurenceb> yeash, not really worth it
[16:52] <M0TEK> is there an rf front end on this thing?
[16:52] <Laurenceb> MOTEK: a frontend
[16:52] <M0TEK> ok cool
[16:52] <M0TEK> a usb stick with an fpga full of downconverters would be an interesting thing :)
[16:53] <Laurenceb> yes, LNA - IQ MIXER - PGA - 8 bit ADC
[16:53] <M0TEK> probably would pull more current than the 2.0 spec would allow
[16:53] <Laurenceb> yeah, this is getting a bit power hungry
[16:53] <Laurenceb> already
[16:53] <M0TEK> cool concept though - will be awesome
[16:54] <SpeedEvil> Laurenceb: seen geotate.com ?
[16:54] <SpeedEvil> Laurenceb: BOM?
[16:54] <Laurenceb> the trickies thing is making all the footprints
[16:54] <Laurenceb> SpeedEvil: I'm not going to go into loads of detail until I get further with the design
[16:54] <Laurenceb> but I may make it GPL
[16:55] <Laurenceb> if I get as far as a pcb and I can sell some myself
[16:57] <M0TEK> if you could make it do gps too.... :)
[16:57] <M0TEK> guess that probably would need the fpga
[16:57] <Laurenceb> sure
[16:57] <SpeedEvil> nope.
[16:57] <SpeedEvil> Not at all.
[16:57] <Laurenceb> it will laugh at gps
[16:57] <SpeedEvil> M0TEK: geotate.com
[16:57] <SpeedEvil> grab 200ms of the GPS signal, process later.
[16:57] <Laurenceb> on a decent processor its easy
[16:57] <M0TEK> for sure, i meant real time
[16:58] <Laurenceb> you could do it realtime on a decent machine
[16:58] <Laurenceb> just probably not too easily on an ARM
[16:59] <Laurenceb> SpeedEvil: you can do it with 1ms
[17:00] <SpeedEvil> Laurenceb: not really
[17:00] <M0TEK> bbiab
[17:00] <SpeedEvil> Laurenceb: you need several navigation bits for disambiguation of time and position.
[17:00] <SpeedEvil> Laurenceb: which means several times 20ms.
[17:00] <Laurenceb> guess so
[17:00] <Laurenceb> no
[17:00] <SpeedEvil> Laurenceb: 1ms is fine if you know pretty accurately where and when you are.
[17:00] <Laurenceb> if you have 4 sats
[17:01] <Laurenceb> and time from the RTC
[17:01] <Laurenceb> to find valid ephemeris
[17:01] <Laurenceb> then you can solve for 3D pos and time
[17:01] <SpeedEvil> and time to around a quarter of a millisecond or so.
[17:01] <SpeedEvil> however.
[17:01] <Laurenceb> no, you only need time to around an hour
[17:01] <SpeedEvil> you lose _lots_ of SNR by not having a whole navigation bit.
[17:01] <Laurenceb> so you can lookup the ephemeris
[17:02] <Laurenceb> hmm
[17:02] <SpeedEvil> You only get the psuedorange to an ambiguity of 300Km with 1ms.
[17:02] <Laurenceb> sure
[17:02] <SpeedEvil> So you have _lots_ of potential positions.
[17:03] <Laurenceb> ok... if you can resolve position to within 300Km
[17:03] <Laurenceb> then you only need 1ms
[17:03] <SpeedEvil> Not quite.
[17:03] <SpeedEvil> You've also got the problem that you can't disambiguate teh time.
[17:03] <Laurenceb> with 4 sats you can
[17:03] <SpeedEvil> range to satellites varies _lots_ within an hour
[17:03] <Laurenceb> sure
[17:04] <Laurenceb> but the ephemeris doesnt
[17:04] <Laurenceb> you can solve it
[17:04] <Laurenceb> for time and position at once
[17:04] <SpeedEvil> Not really IMO.
[17:04] <SpeedEvil> There are several problems.
[17:04] <SpeedEvil> A) Your SNR with only 1ms, not a whole navigation bit is 13dB down or so
[17:05] <SpeedEvil> B) This means that the noise on the doppler frequency you can resolve over one bit is very, very high.
[17:06] <Laurenceb> we arent interested in velocity for geotagging
[17:06] <SpeedEvil> C) You can't disambiguate between tens of hundreds of thousands of successive milliseconds.
[17:06] <SpeedEvil> err
[17:07] <SpeedEvil> C is the problem - it ends up with a huge solution space, with probably not enough clean signal to say 'this was the position'.
[17:07] <SpeedEvil> I note teh above thing logs 200ms.
[17:08] <SpeedEvil> Which isnt' actaully that bad - 18mbits * 200ms is quite managable to store.
[17:08] <SpeedEvil> Plus, 1ms is probably way longer than it'll take to boot, for the PLLs to come up to speed, ...
[17:08] <SpeedEvil> So 20ms or 40ms probably isn't really an issue.
[17:09] <Laurenceb> hmm if we know time from the RTC and rough position I think its solvable
[17:09] <Laurenceb> I was just thinking about minimising the amount of data
[17:09] <SpeedEvil> It's not really an issue.
[17:09] Action: SpeedEvil points at his 4G microSD that was damn near free.
[17:10] <SpeedEvil> That can log for all the time for about half an hour
[17:10] <Laurenceb> guess so, but for some applications
[17:10] <SpeedEvil> Alternatively, you can just snap 200ms every 3 min or so, and that goes for damn near forever.
[17:11] <SpeedEvil> (~500 hours)
[17:11] <SpeedEvil> Take a bit more care with your RTC, and you can probably go way out of that 3 min range.
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[17:13] <SpeedEvil> Maybe throw in a 60s cycle every few hours, if paranoid.
[17:17] <SpeedEvil> If you do manage 1ms, I'll be really, really impressed :)
[17:18] <M0TEK> back
[17:18] <Laurenceb> well I've made a amtlab script that find stats from 1ms data
[17:18] <Laurenceb> well above the noise and I'd say you could fit a pseudorange to within 10m or so
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[17:19] <Laurenceb> so if you have an RTC to within 30 seconds or so and an ephemeris server it should be possible
[17:20] <Laurenceb> oh and you know what country you're in
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[17:21] <SpeedEvil> Right.
[17:21] <SpeedEvil> Now how do you disambiguate that from the next millisecond?
[17:21] <SpeedEvil> Or more accurately 10ms on - since you don't really care about 1ms as the sats will only move 2m or so.
[17:22] <Laurenceb> you solve for 4 variables
[17:23] <M0TEK> yes. This first side-lobe image should work. assuming zero-order hold on the DAC of the DDS
[17:24] <Laurenceb> ?!
[17:25] <SpeedEvil> Laurenceb: you're sampling at the IF or carrier?
[17:25] <Laurenceb> IF
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[17:27] <M0TEK> steve seems to be having issues
[17:28] <SpeedEvil> Laurenceb: what RMS time error do you get from one millisecond to the next?
[17:28] <Laurenceb> SpeedEvil: I dont follow
[17:29] <SpeedEvil> Laurenceb: I'm wondering what you're basing the '10m' on - a guess or have you done numbers on it?
[17:29] <Laurenceb> I've got data, dut from an FFT technique
[17:29] <Laurenceb> *but
[17:30] <Laurenceb> so you then have to fit a triangle
[17:30] <Laurenceb> to the peak, I'm guessing thats going to have an error ~10m from the data
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[17:32] <M0TEK> G8KHW_: issues!?
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[17:39] <SpeedEvil> On bright LEDs.
[17:39] Action: SpeedEvil got a sample 114lm 3.5mm^2 LED from cree.
[17:40] <SpeedEvil> Connecting it up by staring at it really hard, and poking wires from the power supply leads to large blobs in your vision.
[17:40] <Laurenceb> still not amazing
[17:40] <Laurenceb> you need ~1000lm to light a room
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[17:41] <SpeedEvil> yes - but the peak brightness of an emitter that's about 2mm (optical) diameter) is quite large indeed.
[17:41] <Laurenceb> you need an array
[17:41] <SpeedEvil> Sure.
[17:41] <SpeedEvil> LEDs have a ways to go before they're really tehre for room lighting.
[17:41] <SpeedEvil> Largely dropping in price.
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[17:51] <M0TEK> hi rharrison
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[18:11] <Xenion> Guten Abend / good evening :-)
[18:11] <natrium42> hallo
[18:12] <Xenion> :-)
[18:14] <fergusnoble> back from exam
[18:14] <fergusnoble> M0TEK: want to try the repeater?
[18:17] <natrium42> could you repeat what you just said?
[18:17] Action: natrium42 tries fergusnoble :P
[18:21] <M0TEK> fergusnoble: i can't talk to you until you have a callsign
[18:21] <M0TEK> more seriously, it' Chris's b-day so we're about to head out for food/stuff
[18:22] <fergusnoble> M0TEK: its quite active
[18:22] <M0TEK> what freq?
[18:22] <fergusnoble> but ok, have fun
[18:22] <fergusnoble> 433.200
[18:22] <M0TEK> what's the calling freq?
[18:23] <fergusnoble> no calling freq
[18:23] <fergusnoble> with repeaters i think you just wait for quiet and give your callsign
[18:24] <M0TEK> but it can't repeat on the same freq as the input, surely?~
[18:24] <fergusnoble> no, input is 434.800
[18:24] <fergusnoble> but your radio should do that automatically when you press the PTT
[18:25] <M0TEK> but yes it's loud and clear
[18:25] <M0TEK> milton keynes
[18:25] <fergusnoble> yeah
[18:25] <M0TEK> poor company
[18:25] <M0TEK> good luck with that door
[18:26] <fergusnoble> fascinating
[18:27] <M0TEK> norwich aye?
[18:27] <M0TEK> if anything could beat the meaningfullness of that
[18:27] <M0TEK> oh right, a WX report
[18:27] <M0TEK> that is pretty meaningful, as meaningful goes
[18:28] <M0TEK> it's like cockney rhyming slam
[18:28] <M0TEK> through the old XYL down the apple and pears
[18:28] <M0TEK> threw*
[18:28] <M0TEK> wasn't a pretty thing to have a butchers at
[18:29] <hallam> How does the radio know to use a different TX freq?
[18:30] <hallam> and more importantly, could something like that have been why you didn't get through last night?
[18:30] <M0TEK> i think actually you do have to adjust it
[18:30] <fergusnoble> hallam: its a standard to use +600khz
[18:30] <fergusnoble> or something like that
[18:31] <fergusnoble> but thats on FM, were trying ssb last night
[18:32] <fergusnoble> hallam: what are you doing for dinner?
[18:33] <M0TEK> right, am off
[18:33] <M0TEK> catch you later
[18:33] <fergusnoble> ok, bye
[18:33] <hallam> later Ed
[18:33] <M0TEK> don't forget to breathe whilst you listen to the riveting repeater
[18:34] <hallam> fergusnoble: just ate at Browns, though I dare say I'll want more food in a few hrs
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[18:34] <hallam> Hi Steve
[18:40] <RocketBoy> Hey Henry - where abouts are U these days UK?
[18:41] <hallam> yep, Cambridge
[18:41] <hallam> graduate in June with a bit of luck
[18:43] <RocketBoy> Ah OK excellent - got anything lined up after that MSc PHd?
[18:43] <hallam> hoping to work in Boston for a year or two first
[18:43] <hallam> then at least a masters
[18:45] <hallam> how are things with you?
[18:47] <rharrison> Come on HABBERS time for a launch :)
[18:48] <RocketBoy> yep - OK I still have work at the mo - at least until April - I got an interesting sideline working out some satellite radio transmitter linerization code in a FPGA
[18:48] <hallam> that does sound interesting
[18:48] <hallam> is there a decent chance of it actually flying?
[18:48] <RocketBoy> yeah I agree I'm bored - we need to throw somthing into the wind
[18:48] <rharrison> Cool
[18:49] <hallam> we're building a ZP this weekend
[18:49] <hallam> maybe fly it next week if all goes well
[18:49] <rharrison> Right I'm off home will be on later
[18:49] <hallam> see you
[18:49] <rharrison> RocketBoy did you get the post
[18:49] <hallam> RocketBoy, when's the next EARS?
[18:50] <RocketBoy> hallam: excellent can I watch (ZP) - next rocket EARS is 1st March - but we can launch balloons any weekend
[18:51] <RocketBoy> rharrison: sorry yes thanks (banked 2day)
[18:51] <rharrison> Great
[18:51] <hallam> course you can, welcome to come along for the construction too if interested - the weld-o-tron is pretty cool
[18:52] <rharrison> nights all
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[18:53] <RocketBoy> excellent - I may take U up on that
[18:56] <RocketBoy> actually it would be cool to weld-o-tron up a plastic balloon that would fit into the back of my van (sort of cube) - then I could re-use it for HARVe drop tests - so a lesson in weld-o-tronics would be great
[18:57] <hallam> heh, that's a good word
[18:57] <hallam> do you mean one that would fit into your van inflated?
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[18:58] <Laurenceb> this could be useful for parafoil/rogallo tests
[18:59] <hallam> even the proper big ones should fit just fine rolled-up
[19:00] <RocketBoy> hallam: yes - sort of just fit in big
[19:01] <RocketBoy> the idea is to use somthing that has slow diffusion, keep it filled and just top up occasionally
[19:02] <RocketBoy> BBL - tea up
[19:02] <hallam> hm, makes sense I suppose
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[20:01] <Xenion> Gute Nacht alle miteinander ! :--)
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[20:15] <natrium42_> sieben, acht, gute nacht
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[20:19] <rjharrison> do not do a simulation from wyoming with a launch from the Greenwich Meridian
[20:20] <rjharrison> It doesn't like it
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[20:39] <rjharrison> Not that anyones interested but there is a soak test underway on icarus
[20:39] <rjharrison> www.robertharrison.org/tracker
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[20:49] <Hiena> Soak?
[20:49] <Hiena> Landed to the see?
[20:49] <natrium42_> rjharrison: your site isn't loading for me
[20:49] <natrium42_> :S
[20:50] <natrium42_> oh it did now
[20:51] <natrium42_> simulation?
[20:52] <rjharrison> yep
[20:52] <rjharrison> works well with google earth
[20:52] <Hiena> Yup. Looked like a little bit high horisontal speed.
[20:53] <rjharrison> I'm following a kml from wyoming
[20:54] <Hiena> Uhum.
[20:54] <Hiena> Well, i'm heads to the bed,
[20:54] <Hiena> I had eventfull day.
[20:54] <Hiena> Good night all!
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[20:55] <rjharrison> got temp sensor down to -50.1
[20:55] <rjharrison> see www.robertharrison.org/listen/view.php for listener data
[20:56] <rjharrison> two radios listening and logging at the moment
[20:58] <natrium42_> col
[20:58] <natrium42_> *cool
[21:04] <rjharrison> It's working nicly
[21:04] <rjharrison> nicely
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[21:23] <rjharrison> natrium42_ do u know why the web tracker has script errors I'm sure its to do with the number of points
[21:24] <natrium42_> what are they?
[21:24] <rjharrison> script is still rumming
[21:24] <rjharrison> running even
[21:24] <rjharrison> asks if you want to continue
[21:25] <rjharrison> seems to hapen at about 2000 points
[21:25] <natrium42_> which browser are you using?
[21:25] <rjharrison> ie and ff
[21:25] <natrium42_> ah
[21:25] <natrium42_> perhaps your computer is slow
[21:25] <rjharrison> may be
[21:25] <natrium42_> the number of points is too much, probably
[21:26] <rjharrison> I'll let you know when it happens again
[21:26] <rjharrison> yep
[21:26] <natrium42_> so the scropt is taking longer than expected and the browser wants to kill it
[21:26] <rjharrison> yep but it never completes
[21:26] <rjharrison> even after 10 mins
[21:27] <rjharrison> how does balloon order work?
[21:27] <rjharrison> the images on the tracker
[21:27] <rjharrison> The last one is often hidden
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[22:14] <rjharrison> simulations are so much more predicatable
[22:17] <fnoble> natrium42_: can i look at the tracker code?
[22:17] <fnoble> natrium42_: im webifying our landing prediction and want to make a google maps window
[22:19] <Laurenceb> how much power can a 20x55mm pcb dissapate?
[22:22] <epictetus> does it have airflow?
[22:22] <epictetus> a lot more if it has airflow than if it doesn't :P
[22:22] <Laurenceb> not really
[22:22] <Laurenceb> yeah
[22:22] <Laurenceb> may have to add vents in the case
[22:22] <epictetus> i'm guessing only 1-2 watts at the very most
[22:23] <Laurenceb> hmm
[22:26] <Laurenceb> my usb radio design currently uses 450ma :(
[22:27] <rjharrison> fnoble will we be able to use the predictor on our launches after it is webified?
[22:28] <Laurenceb> its going to burn
[22:28] <fnoble> rjharrison: yes
[22:29] <fnoble> rjharrison: will be available to all
[22:29] <rjharrison> cool
[22:29] <rjharrison> Is it like an advanced verison of wyoming?
[22:30] <epictetus> Laurenceb: at 5 volts? so 2.5 watts or so?
[22:30] <Laurenceb> yes
[22:30] <epictetus> i think that's borderline...
[22:30] <rjharrison> Or will it need realtime data
[22:30] <Laurenceb> its the bloody VCO
[22:30] <fnoble> rjharrison: yeah hopefully
[22:30] <rjharrison> fnoble coo
[22:30] <rjharrison> l
[22:30] <rjharrison> nights
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[22:31] <fnoble> rjharrison: also will get it to display in google maps so you dont have to faff with kml files
[22:31] <Laurenceb> the AD parts are very nice in all respects apart from power
[22:34] <epictetus> throw a little heat sink on the vco then
[22:36] <Laurenceb> epictetus: yeah maybe
[22:36] <natrium42_> fnoble: source code is on the wiki
[22:36] <Laurenceb> and the mixer...
[22:36] <Laurenceb> the datasheet suggests a thermal via and heatsink on the back side of the board
[22:37] <Laurenceb> guess it would work - 500ma is possible with usb2.0
[22:39] <M0TEK> evening all
[22:40] <fnoble> M0TEK: webifying the landing prediction
[22:40] <fnoble> progress so far - http://www.srcf.ucam.org/~cuspaceflight/pred/
[22:41] <fnoble> spits out a list of coords, but no map yet
[22:42] <Laurenceb> what does it predict with?
[22:42] <fnoble> GRIB data
[22:42] <M0TEK> fnoble: cool. about time
[22:43] <M0TEK> can you put the predictor on the svn?
[22:43] <fnoble> M0TEK: yeah, will do soon
[22:43] <fnoble> M0TEK: could do with getting the latest stuff from rob first though
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[22:43] <M0TEK> last time I looked at the code it definitely worked but it wasn't pretty
[22:44] <fnoble> does anyone know of a tutorial for creating a google map view? is it hard?
[22:44] <M0TEK> srcf link isn't loading for me currently
[22:44] <M0TEK> I guess natrium42_ is the man to ask :)
[22:44] <M0TEK> the code is on the wiki
[22:44] <fnoble> M0TEK: odd, working for me
[22:44] <M0TEK> it is for me now
[22:44] <M0TEK> just took 30 secs to load
[22:45] <fnoble> strange
[22:45] <M0TEK> drag factor could do with defining, but otherwise looks good
[22:45] <fnoble> M0TEK: was thinking of adding a field where you can just put in the size of a parasheet
[22:45] <fnoble> M0TEK: and a drop down box to choose common launch sites
[22:45] <M0TEK> aaargh
[22:46] <fnoble> i.e. EARS and Churchill
[22:46] <M0TEK> I augmented the burst predictor to do the drag calcs for different chute designs - so will happily give you the sums for that
[22:46] <M0TEK> and the location is definetly something that would help
[22:47] <fnoble> M0TEK: drag calcs would be cool
[22:47] <M0TEK> infact an online burst predictor would be good too
[22:47] <M0TEK> so just 'predict everything' page
[22:47] <fnoble> yeah, can slowly add to it
[22:47] <M0TEK> cuspaceflight.co.uk/predict - could be a useful tool
[22:47] <M0TEK> yeah, cool
[22:48] <M0TEK> ok, will type up the sums for different chute types
[22:48] <M0TEK> probably easier than getting you to decode the cell equations in excel
[22:49] <M0TEK> have got the repeater feeding in here
[22:51] <fnoble> M0TEK: not at home, in the DPO
[22:51] <fnoble> M0TEK: otherwise we could have a chat
[22:51] <M0TEK> been doing anything in the dept?
[22:51] <fnoble> M0TEK: the radio can activate the repeater, i tried it
[22:51] <fnoble> M0TEK: just coding
[22:51] <fnoble> M0TEK: using a screen for the eee
[22:51] <M0TEK> ah ok
[22:51] <M0TEK> fair enough :)
[22:52] <fnoble> M0TEK: and keeping henry company
[22:52] <M0TEK> what's he doing - cfd?
[22:52] <fnoble> progress report and control systems stuff
[22:52] <M0TEK> I have just been out for Chris's b-day
[22:52] <fnoble> i think
[22:52] <fnoble> yeah, fun?
[22:52] <M0TEK> didn't fancy going onto Cindies though
[22:52] <M0TEK> 9,10,11 am's tomorrow
[22:53] <fnoble> cant seem to extract the files from the tracker, something wrong with the timestamps apparently
[22:53] <fnoble> yeah
[22:53] <fnoble> i can understand the desire not to go to cindies
[22:54] <M0TEK> fnoble: it's probably worth grabbing Rob's latest code and then just tarting it up a bit - it was all in one single cpp file last time iirc.
[22:54] <M0TEK> would make it easy to develop if we split it up a bit
[22:55] <fnoble> yeah, there are a few things i have in mind to change
[22:55] <M0TEK> don't do without me though - I'd like to go over it too so i can see exactly what he's done
[22:55] <fnoble> yeah, ok
[22:55] <M0TEK> it's probably worth having several of us comprehend its innards, if we're trusting £££ of kit to it
[22:55] <fnoble> think we should do it with him there too?
[22:56] <M0TEK> sure yeah - though my first instinct would be just to get stuff into header files and rationalise a little - decoding files, predicting files etc
[22:56] <M0TEK> so he might not be that interested
[22:56] <M0TEK> but sure
[22:57] <fnoble> ok
[22:57] <M0TEK> maybe dOxygen. What's your opinion on that? I got into the habit of using it over the summer and it's pretty useful for bigger stuff i guess
[22:57] <M0TEK> maybe that predictor is fairly self explanatory
[22:57] <fnoble> M0TEK: will have a think about it
[22:58] <M0TEK> i guess just decent commenting will be fine. Newbs probably don't want doxygen
[22:58] <fnoble> we should make a wiki for cusf internal faffings
[22:58] <fnoble> like documentation for various things
[22:58] <M0TEK> am thinking about when we get blown up and someone else needs to take over CUSF
[22:58] <M0TEK> fnoble: agreed
[22:59] <M0TEK> definitely need a backup solution first though :)
[23:04] <M0TEK> fergusnoble: if you want to do that friday, I'm around basically all day
[23:04] <M0TEK> not around from sat lunch time though
[23:04] <M0TEK> then it can go up on the svn spick and span
[23:05] <M0TEK> fnoble: even. not fergusnoble
[23:07] <fnoble> M0TEK: should be free on friday a bit
[23:08] <fnoble> saturday is n00b training day
[23:08] <M0TEK> yeah
[23:08] <M0TEK> training them to use the weldomatic anyway
[23:08] <M0TEK> i think to teach them the tracking software you'd really need to hire a minibus and take them on a chase
[23:09] <M0TEK> or at least - using the tracking software to track is probably a more useful exercise
[23:09] <fnoble> yeah, we'll see how it goes
[23:09] <fnoble> might try and steer it round to mainly using the welder
[23:10] <M0TEK> it's probs the more useful exercise
[23:10] <fnoble> as the eee is broken and the tracking software is in a state
[23:11] <M0TEK> these things always are until someone insists on stable releases and dev versions
[23:11] <M0TEK> i guess if it gets publically SVN'd it may sort itself out
[23:11] <fnoble> yeah, we need to have a chat about the best architecture for the whole thing
[23:12] <M0TEK> one for the pub maybe
[23:12] <fnoble> would like to make it a bit cleaner than a random bunch of scripts communicating through a mixture of files and pipes
[23:12] <M0TEK> exactly
[23:12] <M0TEK> although that's basically the unix philosophy :)
[23:14] <fnoble> M0TEK: i think we can do it ths unix way but also make it a bit more sane
[23:14] <fnoble> it mixes paradigms at the moment
[23:14] <M0TEK> well I think web interfaces to things would be useful to lots of people
[23:15] <M0TEK> so web-configurable input files might be a design consideration
[23:15] <M0TEK> this is thinking more about randomers than CUSF - maybe the priorities of CUSF are... more of a priority
[23:18] <fnoble> no, i agree, web interfaces are good
[23:18] <fnoble> even just thinking about us
[23:19] <fnoble> can be accessed anywhere on any platform easily
[23:19] <M0TEK> it's easier for everyone involved. No need to dl gygwin or whatever
[23:19] <M0TEK> cygwin*
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[23:23] <M0TEK> Well, most sim progs I've used seem to take their parameters as XML files.
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[23:31] <M0TEK> right bed
[23:32] <fnoble_> guys, try the landing predictor
[23:32] <fnoble_> M0TEK: wait
[23:32] <fnoble_> check it out
[23:32] <M0TEK> ok
[23:32] <M0TEK> link me again
[23:32] <fnoble_> http://www.srcf.ucam.org/~cuspaceflight/pred/
[23:32] <M0TEK> fnoble_: loads faster now
[23:33] <M0TEK> also, am going to try an all-band (HF/VHF/UHF) tx.
[23:33] <M0TEK> DDSs are so cheap now
[23:34] <M0TEK> drag factor is CdS non?
[23:34] <M0TEK> it works well for me - a link to the kml on the same results page would be awesome too
[23:34] <M0TEK> but it looks good
[23:35] <M0TEK> likewise maybe a launch time in UTC?
[23:35] <fnoble_> yeah, i know there are a few things to add
[23:35] <M0TEK> i think peeps will aprreciate the fact that it doesn't take 30 mins to run
[23:35] <fnoble_> but thought you would want to see the map straight away
[23:35] <M0TEK> it is looking pretty cool
[23:35] <M0TEK> though launching now isn't looking so cool
[23:36] <M0TEK> awesome. right, early night
[23:36] <fnoble_> no, but at least we can check more easily now
[23:36] <fnoble_> ok, gdnight
[23:37] <M0TEK> save the date on friday. there maybe be algorithmic complexity reductions to be found!
[23:37] <M0TEK> like sifting for gold
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[23:43] <Laurenceb> god what are you doing
[23:43] <Laurenceb> 30 minute runtime wtf
[23:43] <fnoble_> Laurenceb: took 30mins to run for you?
[23:43] <fnoble_> didnt take anything like that for me
[23:49] <fnoble_> Laurenceb: ?
[00:00] --- Thu Jan 15 2009