highaltitude.log.20080303

[00:01] <Laurenceb> http://wiki.ukhas.org.uk/ideas:landing_spot_prediction
[00:01] <Laurenceb> I dont see why RocketBoy uses a cos term
[00:01] <Laurenceb> to convert the longitude
[00:02] <Laurenceb> to an bsolute distance, when you can just use it as it is, and you reference frame is a bit scewed, but it shouldnt matter
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[12:50] <RocketBoy> yo
[12:50] <RocketBoy> edmoore - you there?
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[13:16] <edmoore> hi RocketBoy
[13:16] <edmoore> sorry, was lunching
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[13:24] <RocketBoy> ah - just wondered if you went to EARS in the end ?
[13:25] <RocketBoy> oh and do you know where FHALP-2 was found?
[13:31] <edmoore> We did, but didn't launch anything.
[13:31] <edmoore> And FHALP-2 was found in a field withing 300m of cb24 4ra by a farmer
[13:32] <RocketBoy> ah - ta
[13:32] <RocketBoy> do you know if there were any launches at EARS - with my controller?
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[13:35] <Laurenceb> hey RocketBoy
[13:35] <Laurenceb> just emailed you
[13:35] <RocketBoy> ok Laurenceb
[13:36] <Laurenceb> can you get data through?
[13:36] <edmoore> RocketBoy: not to my knowledge. There were no HPR launches that I saw
[13:36] <RocketBoy> OK ta edmoore
[13:37] <RocketBoy> The FHALP-2 landing spot was way off from where we thought
[13:37] <Laurenceb> RocketBoy: with the exception of the timing error, our range tests with fldigi went well
[13:38] <RocketBoy> more like close to the burst point
[13:38] <Laurenceb> we were missing 8dB somewhere, but there was a steel framed building in the line of sight
[13:38] <RocketBoy> well thats the main thing - if it works it works
[13:39] <edmoore> yes it's odd. Am looking forward to seeing some KMLs if james can see them
[13:39] <Laurenceb> have you ever used a radio with your present setup?
[13:39] <Laurenceb> it "works" but the timing error was odd
[13:40] <Laurenceb> RocketBoy: can you get any data through?
[13:40] <RocketBoy> yes - data comes through - but its not much of a test on the bench
[13:40] <Laurenceb> hmm, how does it compare to your radios?
[13:41] <Laurenceb> have you done a scope of your signal into the radio?
[13:41] <Laurenceb> and compared to mine?
[13:42] <RocketBoy> well spectrum wise its quite different IIR - mine is the traditional 2 peaks
[13:42] <Laurenceb> this doesnt make an sense...
[13:42] <Laurenceb> whats you seperation?
[13:42] <RocketBoy> 200Hz
[13:42] <Laurenceb> surely that is impossible?
[13:42] <RocketBoy> nope
[13:42] <Laurenceb> you have to use some bandwidth
[13:43] <RocketBoy> 300baud 200Hz
[13:43] <Laurenceb> or your breaking the shannon limit :P
[13:43] <RocketBoy> the peaks are 200Hz
[13:43] <RocketBoy> the bandwidth must be about 400
[13:43] <Laurenceb> sure, but the data will have to spread them out
[13:44] <Laurenceb> so you wont see two peaks unless you average over a long time period
[13:44] <RocketBoy> perhaps a bit more - id have to measure it
[13:44] <Laurenceb> maybe you should adjust mine with the pot/
[13:45] <RocketBoy> I'll try later
[13:45] <Laurenceb> thanx
[13:46] <Laurenceb> thinking about it, its impossible to have two peaks unless the seperation is quite a bit larger
[13:46] <Laurenceb> or truetty was set up differently, so it averaged for a longer time to do the display
[13:46] <Laurenceb> also, if your sending a string of the same character, as opposed to "pseudorandom" data, it will be different
[13:47] <Laurenceb> I have observed that
[13:47] <Laurenceb> pseudorandom will be better at giving two peaks
[13:47] <Laurenceb> bbl, need to use ssh
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[14:02] <Laurenceb> hi again
[14:02] <Laurenceb> just been running the flight code :P
[14:02] <Laurenceb> RocketBoy: any luck with the radio?
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[14:27] <RocketBoy> yep just fired up the old TX - well its a bit different from what I remember - there are two peaks - but they are a bit wider than the shift frequency - and there is another peak in the middle - this is for random data
[14:39] <RocketBoy> bbl
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[14:44] <jcoxon> afternoon
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[14:48] <RocketBoy> hiya jcoxon
[14:48] <RocketBoy> I see you got FHALP-2 back
[14:49] <jcoxon> hey RocketBoy
[14:49] <jcoxon> indeed i have
[14:49] <RocketBoy> must be the closest landing spot to to the launchspot we have ever had
[14:50] <jcoxon> yeah
[14:50] <jcoxon> i've got the log file off the module
[14:51] <jcoxon> it logged from launch to 01:00am
[14:51] <jcoxon> so it wasn't power failure :-p
[14:51] <jcoxon> actually i think i've worked out why we lost radio contact:
[14:51] <RocketBoy> humm
[14:51] <RocketBoy> ?
[14:51] <jcoxon> the antenna broke off
[14:51] <RocketBoy> ah
[14:51] <jcoxon> the wire ground plane is still there
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[14:51] <jcoxon> but the downward wire has detached
[14:52] <jcoxon> it was soldered and heat shrinked but might have got caught up in the lines down to the camera
[14:52] <RocketBoy> well that would explain it - but as I recall it faded out
[14:52] <jcoxon> yeah
[14:53] <edmoore_> have we a kml yet!?!?!?!
[14:53] <jcoxon> edmoore_, no
[14:53] <jcoxon> hehe
[14:53] <jcoxon> but the log is up
[14:53] <jcoxon> so feel free...
[14:53] <jcoxon> :-p
[14:53] <RocketBoy> well if it broke off it would have stopped quickly
[14:53] <jcoxon> if not i'll do it in a bit
[14:53] <jcoxon> RocketBoy, true
[14:53] <jcoxon> also the cutdown fired
[14:54] <jcoxon> which is a bit odd
[14:54] <jcoxon> as we only reached 11km alt
[14:54] <jcoxon> perhaps there was a power surge
[14:54] <jcoxon> and there was power failure but it reset the module and it would carry on logging
[14:54] <RocketBoy> its the balloon gods toying with us
[14:55] <jcoxon> indeed
[14:55] <jcoxon> there was definietly apogee chaos
[14:55] <jcoxon> http://www.pegasushabproject.org.uk/fhalp2/P1010255.JPG
[14:57] <RocketBoy> humm - chutes under the payload are not expected
[14:58] <jcoxon> its rarely the plan
[14:59] <jcoxon> its all a bit of a mystery
[15:00] <RocketBoy> we get quite a few mysteries dont we
[15:00] <jcoxon> yup
[15:00] <jcoxon> its to do with the fact that events occur usually 20km away
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[15:00] <jcoxon> and they are beyond our control
[15:00] <Laurenceb> RocketBoy: any luck with the radio?
[15:01] <Laurenceb> I'm very confused now....can't see how the two peaks could be so well defined...
[15:02] <RocketBoy> they arn't particularly well defined - but they are there
[15:02] <Laurenceb> are you sure you weren't using way 400 hz seperation before?
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[15:03] <RocketBoy> I could have been
[15:03] <Laurenceb> was your pulse shaping completely sinusoidal?
[15:03] <RocketBoy> well as sine as 12 steps will give you
[15:03] <Laurenceb> ok
[15:04] <Laurenceb> mine uses 156 steps
[15:04] <RocketBoy> should be better
[15:04] <Laurenceb> each is to 8 bit resolution
[15:05] <Laurenceb> we'll I've just got a sim card, so I'll be offline for a bit while I try and get it working
[15:07] <RocketBoy> jcoxon: edmoore_ gave me the post code near the landing spot - have you got any better a clue where it landed?
[15:08] <jcoxon> oh yup
[15:09] <jcoxon> 5215.88980 0000.9359
[15:09] <RocketBoy> spiffing
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[15:25] <RocketBoy> bbl
[15:25] <edmoore_> cya
[15:25] Nick change: edmoore_ -> edmoore
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[15:59] <jcoxon> edmoore, you around?
[15:59] <edmoore> gimme 20
[15:59] <edmoore> just battling dig comms
[16:02] <jcoxon> http://www.pegasushabproject.org.uk/wiki/doku.php/missions:firefly:fhalp-2:flightkml
[16:04] <jcoxon> it seems to land in a different place to where the post code refers to?
[16:05] <jcoxon> must be the postcode thingy on google earth
[16:06] Action: Laurenceb_ heads to roof for flight code testing
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[18:22] <Laurenceb> hi all
[18:22] Action: Laurenceb is screwed
[18:22] <Laurenceb> my gps isnt working and neither is my phone
[18:26] <Laurenceb> jcoxon: can I ask you a favour?
[18:27] <Laurenceb> any chance you could post me that EM-406A you said you'd got spare a while back?
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[18:42] <jcoxon> Laurenceb, yeah i'll do it tomorrow
[18:42] <jcoxon> but you'll have 23km alt limit
[18:42] <Laurenceb> thanks
[18:42] <Laurenceb> I'm going to email rf solutions
[18:43] <Laurenceb> and complain IMO there is a firmware bug
[18:43] <Laurenceb> jcoxon: will it jam up at 23Km ?
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[18:47] <jcoxon> Laurenceb, yup
[18:48] <jcoxon> tis a SIRF III
[18:48] <Laurenceb> is there a reset line?
[18:48] <jcoxon> and no one has seen a SIRF III go above24km
[18:48] <jcoxon> not sure
[18:48] <jcoxon> should be
[18:48] <jcoxon> the gps usual work
[18:48] <jcoxon> as in you can still send commands to it
[18:49] <jcoxon> so i guess it can be reset
[18:49] <Laurenceb> I only have a data line from gps to ngw100
[18:49] <Laurenceb> it would have to use a gpio line
[18:50] <jcoxon> got to dash
[18:50] <jcoxon> bbl
[18:50] <Laurenceb> cya
[18:50] <Laurenceb> :(
[18:51] <Laurenceb> not sure if this will work
[18:51] <Laurenceb> oh well I'd better moan at rfsolutions
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[18:52] <edmoore> jcoxon:
[18:52] <edmoore> I still have your xD card
[18:53] <edmoore> x D
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[19:06] <Laurenceb> bbl
[19:14] <Laurenceb> *&%^& formal hall
[19:14] <Laurenceb> now I'm never going to get any food
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[20:28] <Laurenceb> hey ed
[20:29] <Laurenceb> edmoore: how goes it?
[20:29] <edmoore> not bad thanks, you?
[20:29] <Laurenceb> my gps isnt getting a lock :(
[20:29] <Laurenceb> and my phone isnt working :(
[20:30] <Laurenceb> think the phone is fixable, looks like it uses a pdu string without the message center number
[20:30] <Laurenceb> but the gps is worrying
[20:30] <Laurenceb> I've emailed rfsolutions about it
[20:30] <edmoore> tried a hard reset?
[20:31] <Laurenceb> power cycled it
[20:31] <edmoore> no onboard batt?
[20:31] <edmoore> left it for 2+ hours?
[20:31] <edmoore> etc etc
[20:31] <Laurenceb> but there is a lithium battery on the board... it probably keeps some ram backed up
[20:31] <edmoore> yes
[20:31] <edmoore> that's what I mean
[20:31] <Laurenceb> it gets the time ok
[20:31] <edmoore> loose that or see what the command is for a ram reset
[20:32] <edmoore> often does the trick
[20:32] <Laurenceb> theres no rx line soldered on
[20:32] <edmoore> ah....
[20:32] <edmoore> can you remove the batt?
[20:32] <Laurenceb> and its been epoxied
[20:32] <Laurenceb> I might be able to remove the battery
[20:33] <Laurenceb> its very odd, it was jumping between the correct time and about 5 hours in the future...
[20:33] <Laurenceb> said 0 sats, and no lock
[20:34] <Laurenceb> almost certainly firmware related imo
[20:35] <edmoore> yeah - the batt would be the way to go I think
[20:35] <edmoore> or solder onto rx
[20:35] <Laurenceb> I'll try the batt, theres epoxy over the header
[20:36] <Laurenceb> I would have suggested interference, but its been tested ok before using the ngw100
[20:37] <Laurenceb> interestingly, I've had problems with a sirf2 like this, but power cycling sorted it
[20:38] <Laurenceb> tried to get a lock inside, but no luck after 15 minutes or so, so I went outside and it couldnt get anything, obviously confused the firmware
[20:39] <Laurenceb> this has been running in the basement for several hours, maybe that made it screw up
[20:40] <edmoore> yeah, the ram will probably have a very dodgy and partial almanac built up
[20:40] <edmoore> it needs a complete wipe and to be left to rebuild it, I would reckon
[20:42] <Laurenceb> yes, and the batery seems to be good, after I first tested it, I turned it on about 4 days later in the cellar, and it knew the time correctly
[20:42] <Laurenceb> ok, I have some hope that it will work :P
[20:43] <Laurenceb> PDU strings are confusing me to death :S
[20:43] <Laurenceb> http://www.dreamfabric.com/sms/ looks like the phone takes care of adding on the message center address in some cases...
[20:43] <Laurenceb> I'm getting error 304 :(
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[20:49] <Laurenceb> hi again :P
[20:50] <Laurenceb> presently wading through the ericsson manual.....
[20:51] <Laurenceb> ok, apparently it supports text mode, that would solve a few problems
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[20:53] <Laurenceb> http://www.space.com/scienceastronomy/080303-mars-avalanche.html
[20:55] <Laurenceb> bbl
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[22:26] <Laurenceb> hey all
[22:33] <Laurenceb> RocketBoy: any progress with the radio?
[22:34] <edmoore> Laurenceb: You may aswell keep that question in your clipboard
[22:34] <Laurenceb> hehe
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[22:50] <Laurenceb> if I have some code reading from stdin to stdout, e.g "myprogram"
[22:51] <Laurenceb> can you just "myprogram<input_file >output_file" ?
[23:02] <akawaka> yup
[23:02] <akawaka> in unix anyway
[23:03] <akawaka> not sure about dos
[23:03] <akawaka> anyone know a good source for pc104 single board computers?
[23:04] <edmoore> ebay?
[23:11] <akawaka> seems a little barren
[23:12] <RocketBoy> laurence - I'm not sure what you want me to test - playing with the pots? - I'm not sure how that would help? the tune up tones must show the spacing (deviation) and the other one just sets the centre frequency
[23:13] <natrium42> akawaka, i have one that i don't need
[23:13] <Laurenceb> RocketBoy: are you sure that its the right spacing?
[23:13] <Laurenceb> do your radios look different?
[23:14] <akawaka> natrium42: yeah? what spec?
[23:14] <natrium42> hrm, good question. it was a while ago.
[23:14] <RocketBoy> well the spacing is about right - the spectrum is similar - but different - i'll send a pic
[23:14] <Laurenceb> thanx
[23:15] <Laurenceb> if would be understandable for it to be a little different
[23:15] <Laurenceb> do you have a scope?
[23:18] <RocketBoy> sent
[23:18] <RocketBoy> yep
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[23:19] <Laurenceb> any chance you could compare the signals into the module?
[23:19] <RocketBoy> what is the problem you think you have - timing errors - waveshape?
[23:20] <Laurenceb> nonlinear behaviour
[23:20] <Laurenceb> somewhere
[23:20] <Laurenceb> but those look similar enough
[23:20] <Laurenceb> IMO
[23:21] <natrium42> akawaka, http://www.tri-m.com/products/aaeon/pcm5335.html
[23:21] <natrium42> that one
[23:22] <Laurenceb> but yes, the ultimate test would be to compare the waveshape into the module
[23:22] <RocketBoy> well its difficult to tell with a spectrum - ok for looking where the energy is going - but we really need to look at timing eyes
[23:22] <Laurenceb> yes
[23:23] <RocketBoy> phase distortion
[23:23] <Laurenceb> another possibility
[23:23] <RocketBoy> its difficult to think of any non-linearity as there is very little circuitry - do you mean phase shift?
[23:24] <Laurenceb> as in the output frequency is not a linear function of pwm duty cycle
[23:24] <Laurenceb> maybe they changed the module specs
[23:25] <RocketBoy> I doubt it - probability is low
[23:26] <Laurenceb> argg my cutdown code isnt working
[23:26] <RocketBoy> surly the pwm period is constant - just the mark-space ratio that changes?
[23:26] <Laurenceb> why is everything going wrong
[23:26] <Laurenceb> yep
[23:29] <RocketBoy> so - the circuit is a low pass filter following the PWM
[23:29] <RocketBoy> what rate is the PWM going at
[23:29] <RocketBoy> and what is the LPF set at?
[23:30] <Laurenceb> PWM is 64Khz or so IIRC
[23:30] <Laurenceb> LPF is a few Khz
[23:30] <Laurenceb> I've forgotten
[23:31] <Laurenceb> but it looked good on my scope
[23:31] <RocketBoy> yeah - I thought so too
[23:32] <Laurenceb> are you sure there is an issue?
[23:32] <RocketBoy> nope
[23:32] <Laurenceb> hehe :P
[23:33] <Laurenceb> can you get through long strings of data without it completely corrupting half way though?
[23:33] <RocketBoy> you said there was non-linear behaviour
[23:33] <RocketBoy> I havn't tried very long strings
[23:33] <Laurenceb> I suspected something weird like that, due to the FFT being odd
[23:34] <Laurenceb> yes, thats what I had problems with
[23:40] <jcoxon> RocketBoy, I've uploaded the kml file
[23:42] <RocketBoy> well it seems to loose characters at the beginning for me - about the 1st 16 in a sequence of about 60
[23:43] <RocketBoy> thanks jcoxon
[23:43] <Laurenceb> oh interesting
[23:43] <jcoxon> actually its very similar to the forecast
[23:43] edmoore (n=edmoore@pomegranate.chu.cam.ac.uk) left irc:
[23:43] <jcoxon> just a lot lower altitude
[23:43] <Laurenceb> Rocketboy: maybe best to look at the timing?
[23:43] <jcoxon> right i'm off to bed
[23:44] <jcoxon> night all
[23:44] <Laurenceb> cya
[23:44] <Laurenceb> with a scope
[23:44] jcoxon (n=jcoxon@host86-129-61-253.range86-129.btcentralplus.com) left irc: "Leaving"
[23:46] <Laurenceb> Rocketboy: do you have the source code?
[23:47] <RocketBoy> did you send it to me?
[23:48] <Laurenceb> will do
[23:48] <Laurenceb> sent
[23:48] <RocketBoy> ok - I'll take a llok
[23:50] <Laurenceb> doh I'm using the wrong coordinates for cambridge
[23:51] <Laurenceb> maybe I should just give up :(
[23:54] <Laurenceb> have I made some silly error with the way the tune up pulse transitions into the data?
[23:55] <Laurenceb> basically theres a global variable that makes the ISR for the timer overflow either increment or decrement through the look up table
[23:55] <Laurenceb> and set the pwm to the corresponding lookuptable value
[23:56] <Laurenceb> so you bit bang your data into the variable, and the ISR does the shaping
[23:58] <Laurenceb> the number of ISR calls is also used as a time base
[23:58] <RocketBoy> so the PWM changes arn't syncronised with the pwm clock?
[23:59] <Laurenceb> yes, they happen each timer overflow
[23:59] <Laurenceb> ie when its zero
[00:00] --- Tue Mar 4 2008