highaltitude.log.20100615

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[01:06] <m0tek> CUSF launch on Thursday. Nova 18. More details in the morning!
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[04:00] <natrium42> detailz plz
[04:27] <juxta> hey natrium42
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[04:40] <natrium42> ho juxta
[04:41] <natrium42> hi* sorry
[04:41] <natrium42> typing with one hand
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[06:24] <juxta> whoops
[06:25] <juxta> stepped away for a couple of hours there
[06:25] <juxta> how's plans coming along for your future launches natrium42?
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[07:20] <m0tek> morning all
[07:21] #highaltitude: mode change '+o m0tek' by ChanServ!ChanServ@services.
[07:22] Topic changed on #highaltitude by m0tek!ed@pluto.trinhall.cam.ac.uk: Welcome to #highaltitude - discuss anything to do with high altitude projects (balloons, gliders, etc) www.ukhas.org.uk. Next Launch - NOVA18 17-6-2010 1100hrs CHURCHILL COLLEGE
[07:23] <juxta> hi ed
[07:26] <m0tek> hi Juxta
[07:26] <m0tek> so I may be doing a PhD at Monash. At the risk of revealing my geographical ignorance, we should go for a beer
[07:30] <juxta> m0tek: oh wow, good work :)
[07:30] <juxta> Monash is not far from me
[07:31] <m0tek> awesome
[07:31] <juxta> well, at least as far as Australian measurements go ;)
[07:31] <m0tek> :)
[07:31] <juxta> (about 800km)
[07:31] <m0tek> jesus
[07:31] <m0tek> I think i'd only go 800km for a two week holiday
[07:31] <juxta> haha
[07:32] <juxta> I'm in Melbourne a few times a year
[07:32] <rjharrison> m0tek that will be a change of scean
[07:32] <rjharrison> scene even
[07:32] <m0tek> just a little yep
[07:32] <rjharrison> At least the HAB weather is more constant
[07:32] <juxta> heh
[07:33] <m0tek> This has been noted
[07:33] <m0tek> right, brekky time
[07:33] <juxta> well, Melbourne is a bit tricky - at least for me the windw blow inland, Melbourne I'm betting the winds blow offshore :(
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[08:05] <jcoxon> morning all
[08:07] <griffonbot> @jamescoxon: #peg7 #ukhas #arhab #cusf Peg VII is catching a ride on Nova18. SSTV on 434.075 SSB Martin1 ~ every 3 minutes then 6 RTTY strings [http://twitter.com/jamescoxon/status/16205598687]
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[08:09] <griffonbot> @jamescoxon: #peg7 #ukhas #arhab #cusf Peg VII more info: http://bit.ly/9aR9Je [http://twitter.com/jamescoxon/status/16205716414]
[08:37] #highaltitude: mode change '+o jcoxon' by ChanServ!ChanServ@services.
[08:37] Topic changed on #highaltitude by jcoxon!jcoxon@host86-161-224-112.range86-161.btcentralplus.com: Welcome to #highaltitude - discuss anything to do with high altitude projects (balloons, gliders, etc) www.ukhas.org.uk. Next Launch - NOVA18 17-6-2010 1100hrs CHURCHILL COLLEGE - http://spacenear.us/tracker
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[09:56] <m0tek> hey chaps. so nova 18 on thursday. should be fun, there'll be some toys to listen to. james is flying sstv.
[10:00] <jcoxon> hey MoALTz
[10:00] <jcoxon> oops
[10:00] <jcoxon> hey m0tek
[10:00] <m0tek> hey
[10:00] <m0tek> there you are
[10:03] <jcoxon> thurs looks like nice ground weather
[10:03] <jcoxon> according to the bbc
[10:03] <m0tek> yeah
[10:04] <jcoxon> though the winds have shifted a little south
[10:04] <m0tek> they have a touch. we'll have to keep an eye on it
[10:05] <m0tek> heading towards the other side of milton keynes
[10:05] <jcoxon> yeah
[10:05] <m0tek> if we can dump into that space between milton keynes and bicester, that'd be ideal
[10:06] <jcoxon> we'll have an ideally place listener
[10:08] <jcoxon> shall i email the ukhas list for you?
[10:08] <m0tek> i will iuw
[10:09] <m0tek> touch typing practice
[10:10] <m0tek> I want to get a better mass estimate first
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[10:11] <jcoxon> m0tek, mine is pretty accurate
[10:12] <jcoxon> and i've said that hackspace can have 200g
[10:12] <m0tek> what do you think might happen in 200g?
[10:13] <m0tek> gosh the orange parachutes are heavy beasts
[10:14] <m0tek> http://aeroconsystems.com/cart/products/72_inch_orange_parachute-70-65.html
[10:17] <jcoxon> yeah they are
[10:18] <m0tek> pretty though
[10:18] <jcoxon> haha
[10:19] <m0tek> the quoted mass though is with deployment bag which you wouldn't fly
[10:19] <jcoxon> what size parachute are you going for?
[10:20] <m0tek> perhaps that 72" one
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[11:09] <juxta> wow, 72" is a large chute
[11:09] <jcoxon> juxta, don't want it crashing down!
[11:10] <juxta> how heavy is the payload?
[11:10] <juxta> jcoxon: I'll be flying an FM voice repeater soon
[11:11] <juxta> perhaps 5W or so - should give us a range of several hundred KM for voice contacts, hopefully might even get Melbourne if we use VHF
[11:11] <jcoxon> oh wow
[11:11] <jcoxon> that'll be fun
[11:11] <jcoxon> has it been down before?
[11:11] <jcoxon> in Oz that is
[11:12] <juxta> don't believe so
[11:12] <juxta> at this stage it'll be a simplex repeater - ie record incoming transmission to buffer, then replay it
[11:12] <juxta> once we see how well that works we'll fly a duplex repeater
[11:13] <jcoxon> nice
[11:13] <jcoxon> all the hams are rallying then
[11:13] <juxta> hehe
[11:13] <juxta> well I think it'll be good to see who we can get listening in
[11:13] <juxta> and testing range
[11:14] <jcoxon> yeah
[11:14] <jcoxon> the horizon circle might be useful
[11:14] <juxta> yeah
[11:15] <juxta> I think I'll have to have a fair bit of separation between the repeater & comms payloads though
[11:15] <jcoxon> good plan
[11:15] <juxta> 5W of RF will probably cause havoc for my unshielded boards
[11:15] <russss> tin foil!
[11:16] <russss> (hat)
[11:16] <jcoxon> ping jonsowman Randomskk
[11:16] <juxta> hehe
[11:17] <russss> has it been done in the UK before? You'd need a special license from ofcom presumably.
[11:17] <juxta> dyeing pcb's is a messy business
[11:17] <jcoxon> russss, yes you would
[11:17] <juxta> you guys have rules prohibiting airborne use of radios, right?
[11:17] <jcoxon> i doubt they'd even grant that
[11:17] <juxta> or is it preventing unmanned use?
[11:17] <jcoxon> juxta, well our licence doesn't extend to airbourne use
[11:18] <juxta> that's annoying
[11:18] <juxta> :(
[11:18] <russss> at what altitude does ofcom's influence stop?
[11:19] <russss> because presumably you don't need a license from them to transmit from a satellite, as long as it's on the correct ITU frequency
[11:19] <jcoxon> yeah
[11:19] <jcoxon> i'm not sure
[11:19] <juxta> are ofcom easy to deal with?
[11:19] <russss> I wonder who coordinates satellite downlink frequencies, if anyone
[11:19] <SpeedEvil> When I made my submission to them, I got a reply, though no action.
[11:19] <juxta> our regulatory body (ACMA) are painful to deal with
[11:20] <SpeedEvil> (though I was complaining about the proposed lowering in minimum bitrate for DAB from 128K
[11:20] <juxta> what'd they say SpeedEvil?
[11:21] <SpeedEvil> 'thanks for your submission' - the published regs scrapped the limit, and made it 'whatever the broadcasters choose'
[11:21] <juxta> well a positive outcome then
[11:22] <juxta> what do broadcasters generally use there?
[11:22] <SpeedEvil> no, negative
[11:22] <SpeedEvil> The problem is that they can choose to broadcast 96, to cram in more channels.
[11:22] <juxta> oh, right
[11:22] <SpeedEvil> mp2 as well
[11:23] <juxta> sorry, I missed that - i thought you meant maximum bitrate
[11:23] <juxta> digital radio has just launched here SpeedEvil
[11:24] <juxta> as far as I can tell the percentage of people here who actually care is about 1% - asides from broadcasters and retailers, nobody really seems interested
[11:25] <SpeedEvil> Various.
[11:25] <SpeedEvil> A quick scan reveals from 192 - Radio 3 (BBC) to 80K mono! for a music station.
[11:25] <SpeedEvil> NME radio
[11:26] <SpeedEvil> Oh fuck.
[11:26] <juxta> ouch, 80k
[11:26] <SpeedEvil> I can hear _hideous_ artifacts on a mono 3" speaker
[11:27] <juxta> we've got AM music stations here, which is unpleasant
[11:27] <juxta> 4khz doesn'
[11:27] <juxta> doesn't really do anything justice*
[11:27] <SpeedEvil> Hmm.
[11:28] <SpeedEvil> BBC asian network - broadcasting music in glorious 64K mono
[11:29] <SpeedEvil> OTOH.
[11:29] <SpeedEvil> I do get ~25 actual radio stations that mostly work 'anywhere' around my property.
[11:29] <SpeedEvil> And they are mostly acceptable for non-critical listening on a mono speaker.
[11:37] <Randomskk> jcoxon: ?
[11:45] <jcoxon> hey
[11:45] <jcoxon> i had a question
[11:45] <jcoxon> oh yeah
[11:45] <jcoxon> for ferret is the callsign still orion?
[11:45] <jcoxon> do i need to change hte xml file?
[11:48] <Randomskk> I think we wanted it changed to ferret
[11:50] <jcoxon> okay
[11:50] <jcoxon> any way of finding out if its been change onboard?
[11:50] <Randomskk> not atm but we are reflashing it with new code before launch anyway
[11:51] <Randomskk> so will make sure it says ferret
[11:51] <Randomskk> bbl
[11:51] <jcoxon> okay
[11:51] <jcoxon> will make hte change
[11:55] <jcoxon> done
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[13:41] <fsphil> DAB is pretty much dead now
[13:42] <fsphil> a few non-techy friends got it, said FM sounded better
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[14:18] <fsphil> jcoxon, are you launching tomorrow or Thursday with Nova18?
[14:18] <jcoxon> thurs
[14:22] <jcoxon> am going on the bottom of the flight train
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[14:24] <fsphil> how many payloads?
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[14:24] <jcoxon> ummm pegasus, a school science payload and ferret tracker
[14:28] <jcoxon> are 4 radials really necessary on a 1/4 wave GP antenna?
[14:29] <GW8RAK> Many commercial "white stick" antennas use 3 angled downward.
[14:29] <GW8RAK> There's nothing magical about the number 4, just that the more radials, so the better the ground plane
[14:29] <fsphil> I read that two are the minimum, but antennas might as well be voodoo to me :)
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[14:30] <fsphil> yea GW8RAK, my 2m/70cm has three
[14:31] <GW8RAK> If I had access to an antenna analyser, I'd see what happens when the verticals are bent upwards not downwards
[14:31] <GW8RAK> So inverted on a balloon, it could direct radiation downwards and not towards the horizon
[14:32] <russss> it changes the impedance
[14:32] <russss> if your ground planes are flat then you get 75 ohms
[14:32] <GW8RAK> I believe the impedance decreases
[14:33] <russss> impedance is a black art. It probably does something completely unexpected.
[14:33] <fsphil> are dipoles 75 or 50 ohms?
[14:33] <fsphil> half wave diples that is
[14:33] <fsphil> dipoles too
[14:33] <GW8RAK> Impedance is the easy bit, it resistivity, reactance and radiation resistance which get me.
[14:34] <russss> I think all dipoles are 50 ohms as long as they're straight.
[14:34] <russss> if they're bent around like the driven element on a TV aerial they become 75 ohms
[14:34] <GW8RAK> And far enough away from anything that there is no interaction. But typically, they are somewhere between 50 and 75 ohms
[14:35] <fsphil> ah, so that's why tv coax is 75 ohms
[14:37] <russss> I presume that's because it makes the antennas a bit smaller?
[14:41] <fsphil> I got an "antennas for novices" book a while back... hasn't done me much good :)
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[14:48] <GW8RAK> The best approach with antennas is to try it. If it works, great, if not, then move on.
[14:49] <jcoxon> i've always used a flat GP
[14:49] <jcoxon> think i'll stick with that
[14:49] <GW8RAK> Various people I've come across has sworn that this antenna is great and that one is useless, while someone else will say the opposite.
[14:49] <GW8RAK> V/UHF is a bit different as there are less options.
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[14:50] <jcoxon> regarding radials
[14:50] <GW8RAK> Or should that be, less available options, i.e yagi or quad plus a few odds and ends.
[14:50] <jcoxon> is it the area covered as such thats important
[14:50] <jcoxon> ?
[14:51] <GW8RAK> Yes, the length of radials should be a quarter lambda if I remember correctly, but some say it is important, others don't worry.
[14:51] <GW8RAK> But if you work on a quarter, you won't be far wrong.
[14:51] <jcoxon> cool
[14:51] <jcoxon> right bbl
[14:51] <GW8RAK> For antenna questions have a look at cebik.com
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[17:02] <griffonbot> @sbasuita: RT @jamescoxon: #peg7 #ukhas #arhab Pegasus VII launch Thurs 17/06/10 ~11:00UTC, follow on http://spacenear.us/tracker, chat #highaltitu ... [http://twitter.com/sbasuita/status/16234867143]
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[17:45] <cuddykid> Hi all, connected lassen iQ up to arduino yesterday. However still without antenna (should be arriving tomorrow hopefully!). There seems to be a problem though, when i'm looking at the serial monitor all i'm seeing is $GPGGA and $GPGSV strings, not $GPRMC strings. Is this because I don't have the aerial (so no valid fix) or is it because the lassen is preprogrammed to sent those strings out only? thanks
[17:46] <sbasuita> cuddykid: iirc the only ones you need are gpgga
[17:47] <cuddykid> sbasuita, ok, I wasn't too sure, but I thought it might provide the data I needed! good
[17:48] <cuddykid> also, I'm reading NMEA strings in the serial monitor but my next step is to transfer them to NTX2.. first thing that I thought of was printing them into buffer and then outputting to NTX2 :S would that be the right way to go about it?
[17:48] <DanielRichman> cuddykid, we didn't use the RMCs but rjh does. He hooks up a simple program and reprograms the iQ to output RMCs
[17:49] <jcoxon> cuddykid, there is a gps library for the arduino
[17:49] <jcoxon> tinyGPS
[17:49] <DanielRichman> yes
[17:49] <DanielRichman> cuddykid, re: buffer & direct output to ntx2 you might want to do some modification of the strings
[17:49] <jcoxon> if you use that then all the hard work will be done for you
[17:49] <cuddykid> ok, thanks guys..
[17:49] <DanielRichman> for example: not all the fields are required; cut down on space for slow tx
[17:49] <jcoxon> so you feed the library the serial data
[17:49] <DanielRichman> and retransmit the last good fix if you lose fix
[17:50] <jcoxon> and then you can 'request' the bits you want
[17:50] <cuddykid> jcoxon, i've had a look at that, how would I go about including the files with the arduino script that I upload to the board?
[17:50] <jcoxon> such as time, lat, lon and alt
[17:50] <cuddykid> got it!
[17:50] <jcoxon> cuddykid, you using the arduino environment
[17:50] <jcoxon> ?
[17:50] <cuddykid> yes, i think so, the program downloaded from arduino site
[17:51] <cuddykid> just called "arduino"
[17:51] <jcoxon> you just need to download the library
[17:51] <jcoxon> and copy it to the library directory
[17:51] <jcoxon> they'll be a guide on the arduino website
[17:51] <jcoxon> then you'll be able to select it in the arduino program
[17:51] <cuddykid> jcoxon, thanks, i'll have a look
[17:51] <jcoxon> there are examples included as well
[17:52] <cuddykid> is it relatively easy to do (feeding custom gps data to ntx2)? as i've little programming knowledge
[17:53] <jcoxon> yes
[17:54] <jcoxon> all you do is construct a string with the various components and then you can use the rtty code to send it
[17:54] <jcoxon> cuddykid, http://github.com/jamescoxon/Atlas-Flight-Computer
[17:55] <cuddykid> thanks, I read up on the libraries, now I see!
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[19:38] Nick change: slandersson -> Snomi
[19:42] <griffonbot> @nearsys: My new PCBs are done, expect delivery soon. Meanwhile, getting ready for launch this weekend. #ARHAB [http://twitter.com/nearsys/status/16245511928]
[19:43] <griffonbot> @nearsys: We have a new door prize for GPSL 2010, a geiger counter kit from Electronics Goldmine. #ARHAB #GPSL [http://twitter.com/nearsys/status/16245552600]
[20:22] <Hiena> Hmmm...Question to all: Which frequency would you use for a Lunar orbiter telemetry?
[20:27] <SpeedEvil> I would wonder about laser.
[20:28] <SpeedEvil> A moderately small laser pointed at earth can have quite good SNR.
[20:28] <SpeedEvil> With very low power.
[20:28] <SpeedEvil> And yes, pointing is a bitch.
[20:29] <SpeedEvil> Barring that - can I or can't I get time on a large dish (>>10m)
[20:30] <Hiena> No large dish, but you could get an antenna array from the "lunatics".
[20:30] <SpeedEvil> moonbounce is in some ways a fair bit easier
[20:31] <SpeedEvil> As you've got a damn huge reflector
[20:31] <SpeedEvil> Are you meaning for a few bits/second?
[20:34] <Hiena> Few hundred/sec
[20:35] <Hiena> 10 or 20 bps at the worst case
[20:39] <SpeedEvil> http://images.4chan.org/b/src/1276630276955.jpg :)
[20:39] <SpeedEvil> (sfw, sort-of-on-topic)
[20:40] <SpeedEvil> I think you can get a few hundred bps on ~433MHz or so.
[20:40] <SpeedEvil> With some gain at the top end, maybe a watt, and a quite large antenna array on the bottom
[20:41] <Hiena> The basic idea, making a dozen gramm weight picosattelite, with a small solar powered transmitter, and a lot of lunatic at the ground level with a real time processing power.
[20:43] <SpeedEvil> I think you're going to really struggle with that.
[20:43] <Hiena> With enough feed, possible to improve the S/N ratio, and tracking the orbit.
[20:43] <SpeedEvil> If it was round earth, it would be 'easy' - as you can point with a magnetorquer.
[20:44] <SpeedEvil> And then use a laser pointer.
[20:44] <SpeedEvil> Round the moon, orientation gets horribly messy
[20:45] <SpeedEvil> I don't think lots of stations will help that much, and they mandate using common freqs too.
[20:45] <SpeedEvil> Which may boost noise.
[20:45] <SpeedEvil> Noise only drops by 1/sqrt(stations) - so it's not that helpful.
[20:46] <SpeedEvil> Even 10000 stations, you're only at 1/50thish of noise
[20:46] <SpeedEvil> Unless I'm missing something
[20:46] <Hiena> Nah, on the satellite i would prefer the sphere radiation characteristic. It would mess the output power, but saves the "earth tracking".
[20:46] <SpeedEvil> I would also consider something different.
[20:47] <SpeedEvil> You can get GPS lock easily out at the moon, with modest, or with current chipsets - no antenna.
[20:47] <SpeedEvil> This would in principle let you broadcast a _really_ long spread spectrum code.
[20:48] <SpeedEvil> So - say - 2.4GHz - with a 10MHz spread code, lasting a couple of minutes gets you a gain of around a billion
[20:49] <Hiena> The problem, is the weight and the . A single GPS chipset would weight as the whole configuration.
[20:49] <SpeedEvil> not really.
[20:49] <SpeedEvil> Look at the weight of the raw venus chip say
[20:49] <Hiena> Ho much is the power cost?
[20:50] <SpeedEvil> Interesting question.
[20:50] <SpeedEvil> When I was looking at this, I was looking at something like a couple of wings made of 2 emcore space-rated cells sandwicthed back-back
[20:51] <SpeedEvil> And a small li-ion battery
[20:51] <Hiena> I would rather burn the mW-s at the output stage instead of the GPS.
[20:51] <SpeedEvil> The GPS lock means you can in some cases make 9 or 10 orders of magnitude smaller the search space.
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[20:53] <SpeedEvil> Using a .1ppm oscillator - say - will give the same performance - once locked - but getting that lock will be many orders of magnitude tougher.
[20:53] <jcoxon> evening
[20:53] <SpeedEvil> evening
[20:54] <Hiena> The satellite radiation would be non directional.
[20:55] <SpeedEvil> Yes, I'm not meaning lock in terms of lock pointing.
[20:55] <SpeedEvil> But code-phase lock to a CDMA signal
[20:56] <SpeedEvil> GPS itself uses a 1024 bit (in some ways a 1024*50 bit) sequence to get an effective power gain of several tens of thousands.
[20:57] <jonsowman> oh dear. fail
[20:57] <Hiena> Well, the other case is the "high power" bursts.
[20:58] <jcoxon> jonsowman, you around for the launch on thurs?
[20:59] <jonsowman> jcoxon: no sorry
[20:59] <jonsowman> I could have done tomorrow
[20:59] <SpeedEvil> Hiena: CDMA lets you trade high bandwidth for high power.
[20:59] <jonsowman> but I'm busy Thursday
[20:59] <jcoxon> oh well
[20:59] <jonsowman> shame really
[21:00] <jonsowman> what time is it - do you know?
[21:00] <SpeedEvil> Hiena: More accurately, it lets you ignore the vast majority of the noise, as it doesn't match your spreading code.
[21:01] <SpeedEvil> Hiena: It's pretty impractical to get a megawatt pulse transmitter in a 10g package. It is not impossible to get a transmitter that - once you go through the spread spectrum modulation/demodulation - appears to be a megawatt.
[21:01] <SpeedEvil> It's very tricky, but it is not impossible.
[21:04] <Hiena> Well there is always a catch.
[21:05] <SpeedEvil> Yes.
[21:05] <SpeedEvil> The catch with CDMA is that until you're locked to the transmitter - you can't tell it's not noise.
[21:05] <SpeedEvil> This is where GPS can let you sidestep that somewhat.
[21:06] <SpeedEvil> In the 0th cut - by simply providing an accurate timebase, which reduces the problem from a o(n^2) problem to o(n).
[21:07] <SpeedEvil> Ideally, by timing to an absolute reference point in spacetime, so reducing the problem to o(n/1000000)
[21:11] Action: jcoxon hates waiting for GPS modules to get a lock
[21:14] <Hiena> Well, i prefer the simple solutions.
[21:14] <SpeedEvil> Sure.
[21:14] <SpeedEvil> Simple solutions don't really exist if you want to pick up a few tens of milliwats from an omni directional antenna on the moon
[21:15] <SpeedEvil> Unless you have a stupidly large dish.
[21:16] Action: SpeedEvil wishes there was a nice hedgetrimming solution.
[21:17] <SpeedEvil> I have done 5m of a 30m hedge - and it's taken a couple of days of solid work.
[21:41] <jcoxon> ping RocketBoy|Away
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[22:03] Nick change: RocketBoy|Away -> RocketBoy
[22:03] <RocketBoy> jcoxon: pong
[22:04] <jcoxon> yeah was wondering about what gain does with the sstv code
[22:04] <jcoxon> seems to make it lighter or darker
[22:04] <jcoxon> so am going to leave it default
[22:07] <RocketBoy> Iy just makes the frequency deviation greater - so should be adjusted so that sync level and peak level more or less fill the passband of the reciver
[22:07] <RocketBoy> I think the default value was set up to be just about right
[22:08] <RocketBoy> based on testing we did
[22:08] <RocketBoy> Iy = It
[22:08] <jcoxon> yeah its just right
[22:08] <jcoxon> you around on thurs?
[22:08] <RocketBoy> Well I could be
[22:09] <RocketBoy> when R U planning to launch time wise
[22:09] <jcoxon> i think ed is thinking 11am
[22:10] <RocketBoy> OK I'll check my calender at work tomorrow
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[23:53] <bfirsh> hello jcoxon!
[23:53] <bfirsh> I suddenly got excited about high altitude stuff again yesterday
[23:53] <bfirsh> and uh, it's been a while....
[23:53] <bfirsh> :)
[23:54] <SpeedEvil> :)
[23:56] <bfirsh> (somebody fill me on the past 3 years or so.... what have I missed?)
[23:57] <bfirsh> well actually the one thing I really want to get back to work on is the glider
[23:57] <bfirsh> it's silly, because I have all the bits
[23:57] <bfirsh> they're just not all put together
[23:57] <bfirsh> and there's so half written software kicking around
[23:58] <bfirsh> the one blocker back in the day (heh) was the radio
[23:58] <bfirsh> is there any progress on two way radio?
[23:59] <SpeedEvil> Some experiments have been done on two-way radio
[23:59] <SpeedEvil> laurenceb has flown a rolago once - though it broke mechanically, it worked in other ways.
[23:59] <SpeedEvil> And he's sort-of-ready for another launch.
[00:00] --- Wed Jun 16 2010