highaltitude.log.20070421

[00:00] <Laurenceb> are you going to do temperature compensation?
[00:00] <rocketboy> Nah
[00:00] <Laurenceb> guess its not needed for initial tests
[00:01] <rocketboy> I'm going to use the GPS to correct any drift - and changes in scale only create small errors
[00:01] <Laurenceb> but the null point especially drifts a lot
[00:01] <Laurenceb> yes guess that what your saying
[00:02] <rocketboy> yep
[00:02] <Laurenceb> interesting idea
[00:02] <Laurenceb> but when the glider is first launched it could go out of control
[00:03] <Laurenceb> very cold+no time to calibrate
[00:03] <rocketboy> yeah - guess it will just have to wait to build up speed
[00:03] <rocketboy> mechanically trimmed at takeoff
[00:04] <Laurenceb> If I can get my peltier working it should be possible to do temperature calibration
[00:04] flowolf (n=flowolf@host162-224.pool80117.interbusiness.it) left irc: "Leaving"
[00:04] <rocketboy> cetrainly a good way of doing it
[00:04] <Laurenceb> AD have some good advice on their website
[00:04] <rocketboy> wow my spelling/typing is getting worse
[00:05] <Laurenceb> use multiple points, with repeated readings, then do polynomial fit
[00:05] <Laurenceb> and use that for look up table
[00:05] <Laurenceb> lol
[00:05] <rocketboy> its a murata one
[00:06] <Laurenceb> shouldnt be make dependant
[00:06] <rocketboy> yeah - somthing like that
[00:06] <Laurenceb> theres less data, but seem to remember murata have less null drift
[00:06] <rocketboy> ah Ok
[00:07] <Laurenceb> AD are good noise wise, but lots of drift
[00:07] <Laurenceb> but its very repeatable drift
[00:07] <Laurenceb> they claim bown to 1 degree per minute drift when calibrated
[00:08] <Laurenceb> sorry I'm calling 2 different things drift
[00:09] <Laurenceb> drift1= null point and sensitivity drift2 = heading error
[00:10] <rocketboy> I don't think sensitivity changes (what I called scale) will be significant
[00:10] <Laurenceb> anyway I'd better be off, lots to do tomorrow, might not be around on IRC for a while, work ect
[00:10] <Laurenceb> yep
[00:10] <Laurenceb> cya then
[00:10] <rocketboy> - its effectivly a bit more proportional gain
[00:11] <rocketboy> yeah cu
[00:11] Laurenceb (i=Laurence@client0163.vpn.ox.ac.uk) left irc:
[00:11] rocketboy (n=steve@host86-132-35-149.range86-132.btcentralplus.com) left irc: "Leaving"
[00:14] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[00:20] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[00:48] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[01:30] icez_ (n=icez@ip68-3-56-121.ph.ph.cox.net) joined #highaltitude.
[01:46] snoopl3s (n=Snoopl3s@209.105.206.80) joined #highaltitude.
[01:46] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) left irc: Read error: 110 (Connection timed out)
[06:56] borism (n=borism@195-50-205-24-dsl.krw.estpak.ee) joined #highaltitude.
[07:36] edwardmoore (n=edwardmo@88.212.167.121) joined #highaltitude.
[07:38] icez_ (n=icez@ip68-3-56-121.ph.ph.cox.net) left irc: Remote closed the connection
[07:42] edwardmoore (n=edwardmo@88.212.167.121) left irc:
[09:29] flowolf (n=flowolf@host162-224.pool80117.interbusiness.it) joined #highaltitude.
[11:28] flowolf (n=flowolf@host162-224.pool80117.interbusiness.it) left irc: "Leaving"
[11:33] flowolf (n=flowolf@host162-224.pool80117.interbusiness.it) joined #highaltitude.
[12:50] flowolf (n=flowolf@host162-224.pool80117.interbusiness.it) left irc: Read error: 110 (Connection timed out)
[14:03] edwardmoore (n=edwardmo@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[14:10] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) joined #highaltitude.
[14:10] <jcoxon> hey all
[14:15] snoopl3s (n=Snoopl3s@209.105.206.80) left irc: Remote closed the connection
[14:15] snoopl3s (n=Snoopl3s@209.105.206.80) joined #highaltitude.
[14:32] snoopl3s (n=Snoopl3s@209.105.206.80) left irc: Remote closed the connection
[14:32] snoopl3s (n=Snoopl3s@209.105.206.80) joined #highaltitude.
[15:03] flowolf (n=flowolf@host57-237.pool80117.interbusiness.it) joined #highaltitude.
[15:19] msweeney (n=martinzi@devonshire-pc080-253.student-halls.leeds.ac.uk) joined #highaltitude.
[15:19] <msweeney> afternoon all
[15:21] <jcoxon> hey msweeney
[15:22] Action: jcoxon is battling with his damn radio
[15:22] Action: msweeney got his Rockwell GPS yesterday
[15:23] <msweeney> also, I found out that my friend who lives in the states was coming back to the UK for the weekend, tried to order the gumstix to save shipping...but visa wouldnt let me ship to the states and bill to the UK.
[15:24] <jcoxon> oh
[15:24] <jcoxon> not good
[15:24] <msweeney> nope
[15:24] <msweeney> so they locked my cards
[15:24] <msweeney> supposedly for my own safety, but quite annoying
[15:24] <msweeney> how's the radio going?
[15:25] <jcoxon> hmmm
[15:25] <jcoxon> i've got it to decode the morse
[15:25] <jcoxon> but its a little unreliable
[15:25] <jcoxon> so gonna spend some time checking connections etc
[15:25] <jcoxon> am now seeing if i can get rtty to work
[15:25] <jcoxon> so i can send data
[15:25] <msweeney> cool
[15:26] <msweeney> I think im gonna go for a bbq, tis nice outside
[15:26] Action: msweeney offs
[15:26] msweeney (n=martinzi@devonshire-pc080-253.student-halls.leeds.ac.uk) left irc: "ChatZilla 0.9.78.1 [Firefox 2.0.0.3/2007030919]"
[16:19] flowolf (n=flowolf@host57-237.pool80117.interbusiness.it) left irc: "Leaving"
[16:19] flowolf (n=flowolf@host57-237.pool80117.interbusiness.it) joined #highaltitude.
[17:01] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) joined #highaltitude.
[17:50] snoopl3s (n=Snoopl3s@209.105.206.80) left irc: Remote closed the connection
[17:51] snoopl3s (n=Snoopl3s@209.105.206.80) joined #highaltitude.
[18:03] snoopl3s (n=Snoopl3s@209.105.206.80) left irc: Read error: 104 (Connection reset by peer)
[18:03] snoopl3s (n=Snoopl3s@209.105.206.80) joined #highaltitude.
[18:36] flowolf (n=flowolf@host57-237.pool80117.interbusiness.it) left irc: "Leaving"
[18:38] flowolf (n=flowolf@host57-237.pool80117.interbusiness.it) joined #highaltitude.
[18:52] snoopl3s (n=Snoopl3s@209.105.206.80) left irc: Remote closed the connection
[18:55] snoopl3s (n=Snoopl3s@209.105.206.80) joined #highaltitude.
[20:13] <jcoxon> edwardmoore, you around?
[20:13] <edwardmoore> aye
[20:14] <edwardmoore> am in cam now
[20:14] <jcoxon> ooo cool
[20:14] <jcoxon> i'm having issues with rtty etc
[20:15] <jcoxon> basically if i send data it doesn't decode correctly
[20:15] <jcoxon> for example if i send "test" i get "swhye"
[20:15] <jcoxon> if i do it again i get the smae
[20:15] <jcoxon> same
[20:15] <jcoxon> so it must transmit the same data
[20:15] <edwardmoore> yep ok
[20:15] <edwardmoore> so...
[20:16] <edwardmoore> obvious patronising questions- baud rate, parity, etc etc all double checked?
[20:16] <jcoxon> well yeah i'm trying to work that out
[20:16] <jcoxon> on cocoamodem there is a waterfall
[20:16] <jcoxon> and when i send data i see 2 bands
[20:16] <jcoxon> of data
[20:17] <jcoxon> so i've set up the shift to be the space between them
[20:17] <jcoxon> (you get to position 2 lines so i've positioned them over the bands)
[20:18] <edwardmoore> yeah
[20:18] <edwardmoore> hmmmm
[20:19] <jcoxon> baud is 50
[20:19] <jcoxon> i've set the serial port to 50
[20:19] <jcoxon> and the other one is the mark
[20:20] <edwardmoore> how is the output coupled to the inpuit?
[20:20] <jcoxon> on the radio reciever side?
[20:21] <jcoxon> i've got it going through a lead out of the radio speaker port into my audio in
[20:21] <jcoxon> (i got one of those usb audio ins
[20:21] <edwardmoore> do you get any better if you use speaker and mike and keep quiet?
[20:22] <edwardmoore> speakers*, mic*
[20:24] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) left irc: "This computer has gone to sleep"
[20:25] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) joined #highaltitude.
[20:25] <jcoxon> oops knocked the cable out
[20:26] <jcoxon> hmmm don't really make any difference
[20:26] <jcoxon> still get random characters
[20:26] <jcoxon> i've got morse working
[20:27] <edwardmoore> in that case i can only think it's some kinda of setting somehwre that's dicking you about
[20:27] <edwardmoore> the loop is working if the morse is working
[20:27] <jcoxon> so does rs232 directly translate to rtty?
[20:27] <edwardmoore> nope
[20:28] <edwardmoore> different animals annoyingly
[20:28] <jcoxon> when there is our problem then
[20:28] <jcoxon> how did henry decode it then?
[20:28] <edwardmoore> lol :)
[20:28] <edwardmoore> he *encodes* the telem into rtty
[20:28] <edwardmoore> you'll have to write a bit-bashing thing for it
[20:28] <jcoxon> no no
[20:28] <edwardmoore> it's very easy to do on pics... :p
[20:29] <jcoxon> henry and i did an experiment
[20:29] <jcoxon> we feed ttl rs232 data
[20:29] <edwardmoore> oh i'm with you
[20:29] <edwardmoore> hmmm
[20:29] <jcoxon> and he manged to decode it
[20:29] <jcoxon> i've just done it again
[20:29] <jcoxon> but obviously can't decode it
[20:29] <edwardmoore> well he might have plugged the output of the radio into a freqnecy to voltage converter
[20:29] <edwardmoore> he's got some way of turning a beep into 5v, obc
[20:30] <edwardmoore> or he has an rs232 setting on his decoding software
[20:31] <jcoxon> hmmm
[20:31] <edwardmoore> i have to go
[20:31] <jcoxon> np
[20:32] <jcoxon> cya
[20:32] <edwardmoore> but will probs be arounbd later
[20:32] <edwardmoore> toodle
[20:52] flowolf_ (n=flowolf@62.211.203.93) joined #highaltitude.
[20:55] snoopl3s_ (n=Snoopl3s@209.105.206.80) joined #highaltitude.
[20:55] snoopl3s (n=Snoopl3s@209.105.206.80) left irc: Read error: 104 (Connection reset by peer)
[21:06] flowolf (n=flowolf@host57-237.pool80117.interbusiness.it) left irc: Read error: 110 (Connection timed out)
[21:59] rocketboy (n=steve@host86-148-221-43.range86-148.btcentralplus.com) joined #highaltitude.
[22:02] <jcoxon> evening rocketboy
[22:04] <rocketboy> hi jc - hows it going - I'm just making a RC servo snooper - monitors the pulse width being sent to a servo and converts it into serial
[22:05] <rocketboy> its for for the next step in the parafoil work - I also have a rate gyro hooked into the payload controller
[22:05] <jcoxon> ooo that sounds cool
[22:05] <jcoxon> excellent
[22:05] <jcoxon> hehe after writing that email about stagnation etc i've had a hectic work week
[22:05] <jcoxon> been doing some radio work for Peg V
[22:06] <jcoxon> and have run into an issue - wonder if you could help
[22:06] <rocketboy> sure
[22:06] <jcoxon> basically its to do with sending ttl rs232 signals down the radio
[22:06] <jcoxon> henry managed to decode it
[22:06] <jcoxon> but i'm stuggling
[22:07] <jcoxon> i recognise that rs232 isn't rtty
[22:07] <rocketboy> I guess you are using cocomodem and henry was using true tty
[22:07] <jcoxon> okay
[22:07] <jcoxon> so there is a special setting on true tty?
[22:08] <rocketboy> you need to set it up as per the serial - speed databits stop/start bits
[22:08] <rocketboy> also shift - what reciver are you using?
[22:08] <jcoxon> i've got the nova one right now
[22:09] <rocketboy> ok and you have it on SSB
[22:09] <rocketboy> ?
[22:09] <jcoxon> so setting the baud rate isn'tenough
[22:09] <jcoxon> i've got the option for LSB and USB
[22:10] <rocketboy> yeah - also the sense - data hi or data lo can correspond with a high or low shift in frequency
[22:10] <jcoxon> would that be "normal" and "reversed"?
[22:10] <rocketboy> if yo swap from USB to LSB the (hi/lo) sense of signal change
[22:10] <jcoxon> right
[22:11] <rocketboy> actually there are so many things to get right i get it wrong sometimes
[22:11] <rocketboy> yeah rormal/reveresed
[22:12] <rocketboy> try both
[22:12] <rocketboy> also shift - can you see a frequency spectrum on cocomodem
[22:13] <rocketboy> ?
[22:13] <jcoxon> yup
[22:13] <jcoxon> basically i see 2 lines of yellow
[22:13] <jcoxon> its a waterfall spectrum
[22:13] <rocketboy> best to use that to estimate the shift of the two frequences being used - then set cocomodem up to that shift
[22:13] <jcoxon> and so i've used them to line up hte 2 green lines that correspond to the shift
[22:14] <rocketboy> it will be like 200, 300 850Hz ...
[22:14] <rocketboy> yep
[22:15] <jcoxon> whats mark?
[22:15] <rocketboy> thats one of the 2 frequencies - one is mark - the other space
[22:16] <jcoxon> okay
[22:16] <rocketboy> its also the data high/data lo from the USART
[22:16] <jcoxon> and mark and space are seperated by shift?
[22:16] <rocketboy> yep
[22:16] <jcoxon> okay
[22:16] <jcoxon> so i've lined them all up
[22:16] <jcoxon> and i get garbled text
[22:16] <jcoxon> now when i send "text"
[22:16] <rocketboy> space is the signal sent between characters - its the value of the stop bit
[22:17] <jcoxon> i get "swhye"
[22:17] <jcoxon> but its the same every time
[22:17] <rocketboy> try it the other way round
[22:17] <jcoxon> so i guess its a matter of just getting the setting right
[22:17] <rocketboy> yep - normally
[22:18] <rocketboy> it sounds like mark/space sense or speed is wrong
[22:18] <jcoxon> hmmm i can't find anywhere to set up the bits etc
[22:18] <rocketboy> poss. it may be automatic
[22:19] <rocketboy> on truetty its ASCII7 or ASCII8
[22:19] <rocketboy> 7 and 8 bit data respectyivly
[22:22] <jcoxon> ooo i just found the user guide
[22:23] <rocketboy> it always helps ;-)
[22:25] <jcoxon> i'm using about a 600 shift
[22:25] <jcoxon> does that sound about right?
[22:26] <rocketboy> about - it depends on the circuit - and the potential divider values you used
[22:26] <rocketboy> what sort of shift can you see on the dispaly?
[22:27] <rocketboy> you should see 2 peaks
[22:27] <jcoxon> its about 600
[22:27] <jcoxon> yeah
[22:27] <rocketboy> thats ok then
[22:27] <rocketboy> and the green lines are lined up?
[22:27] <jcoxon> i'm also lookinghttp://homepage.mac.com/chen/cocoaModemPage/UsersManual/RTTY/index.html#basictuning
[22:27] <jcoxon> oops:
[22:27] <jcoxon> http://homepage.mac.com/chen/cocoaModemPage/UsersManual/RTTY/index.html#basictuning
[22:28] <jcoxon> i get a different shape to fig 5
[22:28] <jcoxon> mine looks like more of a cross
[22:29] <rocketboy> I suspect thats becuse there is no shaping
[22:29] <rocketboy> - the bit i do in the D2A in the pic
[22:30] <jcoxon> right
[22:30] <rocketboy> but you get 2 peaks on the spectrum in fig 1
[22:31] snoopl3s_ (n=Snoopl3s@209.105.206.80) got netsplit.
[22:31] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) got netsplit.
[22:31] snoopl3s_ (n=Snoopl3s@209.105.206.80) returned to #highaltitude.
[22:31] icez (n=icez@ip68-3-56-121.ph.ph.cox.net) returned to #highaltitude.
[22:31] <jcoxon> yeah i've got 2 peaks
[22:32] <jcoxon> hmmmm
[22:32] <jcoxon> "aaaaaaa" gives me "eeeeeee"
[22:33] <jcoxon> with normal rx polarity
[22:33] <jcoxon> or "44444444" with reversed
[22:34] <rocketboy> OK - I think its becuse its RTTY - which is a 5 bit code
[22:34] <rocketboy> and not ascii - I cant find the ascii option at the mo
[22:34] <jcoxon> hmmm i've got another rtty decode i could use
[22:35] <jcoxon> not so pretty or easy to use
[22:35] <rocketboy> maybe its "wideband RTTY?
[22:37] <jcoxon> that just really gives me the waterfall specturm
[22:39] <rocketboy> yeah - that something esle
[22:39] <rocketboy> else
[22:45] <rocketboy> OK - i can't find a ascii RTTY option - so i suspect it doesn't do it
[22:45] <jcoxon> hmmm yeah
[22:46] <rocketboy> - not the end of the world - you can send RTTY
[22:46] <jcoxon> true
[22:46] <jcoxon> though i might stick to morse for this launch
[22:46] <jcoxon> as i haven't tested it
[22:46] <jcoxon> shouldn't get ahead of myself
[22:47] <rocketboy> its not too difficult - even with a 8 bit USART - you just have to set some of the databits as stop/start bits
[22:48] <rocketboy> it will be a bit slower - because the stop bits will be longer
[22:49] <jcoxon> right
[22:49] <rocketboy> need to set D0 to D2 to 1
[22:49] <rocketboy> and put the data in D3 to D7
[22:50] <rocketboy> this is the code for the 5 data bits http://en.wikipedia.org/wiki/Baudot_code
[22:51] <jcoxon> thanks
[22:52] <rocketboy> humm - no changed my mind set D5 to D7 to 1 - and put the data in bits D0 to D4
[22:52] <jcoxon> not really sure how i would go about this with my payload
[22:52] <jcoxon> without pure bit bashing with a gpio line
[22:53] <rocketboy> Ah - so your not using a USART?
[22:54] <jcoxon> well
[22:54] <jcoxon> i was using a UART on the gumstix
[22:54] <jcoxon> which can also be a gpio for morsecode
[22:54] <jcoxon> i was just sending data through
[22:56] <rocketboy> OK - you just need to convert it to RTTY bauadot code
[22:56] <rocketboy> it just a lookup table + sending a cople of "shift" characters
[22:58] <rocketboy> for example to send A - you need to send 11100011
[22:58] <rocketboy> and B would be 11111001
[22:59] <rocketboy> in order to send a sequence of letters you send 11111111
[23:00] <rocketboy> and then to swap to sending digits you send 11111011
[23:01] <rocketboy> thse are values to send to the USART - that make it look like its sending 5 bit baudot rather than ascii
[23:02] <jcoxon> okay
[23:02] <jcoxon> need to look into serial port programming then
[23:03] <rocketboy> you could try sending 11111111 11101010 11101010 11101010 11101010 - which is letters RYRY
[23:12] <jcoxon> a job for tomorrow methinks
[23:12] <jcoxon> thanks rocketboy for the help
[23:13] <rocketboy> noprobs
[23:13] <rocketboy> bbl
[23:13] <jcoxon> i'm off
[23:13] <jcoxon> night all
[23:13] jcoxon (n=jcoxon@jac208.caths.cam.ac.uk) left irc: "Leaving"
[23:39] edwardmoore (n=edwardmo@pomegranate.chu.cam.ac.uk) left irc:
[23:40] edwardmoore (n=edwardmo@pomegranate.chu.cam.ac.uk) joined #highaltitude.
[23:49] rocketboy (n=steve@host86-148-221-43.range86-148.btcentralplus.com) left irc: "Leaving"
[23:59] Laurenceb (n=laurence@host86-139-56-109.range86-139.btcentralplus.com) joined #highaltitude.
[00:00] --- Sun Apr 22 2007