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[08:10] <NigeyMoby> Wee
[08:21] <NigeyMoby> Oh dear
[08:22] <NigeyMoby> sohowww.nascom.nasa.gov/data/realtime/eit_304/1024/latest.jpg
[08:22] <NigeyMoby> Cme anyone?
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[12:14] <Laurenceb> anyone here got a zl special yagi?
[12:14] <Laurenceb> from moonraker
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[12:21] <Laurenceb> im confused by the feed instructions :/
[12:21] <Laurenceb> *im confused by the ms paint mess that is the assembly manual
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[12:22] <GW8RAK> Haven't got one. What are you stuck on?
[12:23] <Laurenceb> well, for a start the instructions seem to be talking about some sort of tuning cap
[12:23] <Laurenceb> but there isnt one in the parts
[12:24] <Laurenceb> some forum posts are talking about a trimmed coax based cap or something...
[12:24] <Laurenceb> also theres no diagram of how to feed it
[12:25] <GW8RAK> Just googled a bit and there are some comments about all zl specials being buggers to tune.
[12:25] <GW8RAK> I have some information at home on them and will have a look tonight.
[12:25] <Laurenceb> http://www.google.com/url?sa=t&source=web&cd=6&ved=0CDUQFjAF&url=http%3A%2F%2Fwww.hamuniverse.com%2Fgi6jpozl-special.pdf&rct=j&q=zl-special%20assembly&ei=dtX8TJW4FcqzhAf-pq0r&usg=AFQjCNGTDUJl8Q3Lstocsp0we0cS0t4S2Q&cad=rja
[12:25] <Laurenceb> seems to explain it
[12:27] <GW8RAK> If I'm reading it correctly, there is a short piece of coax and it is the capacitance between the inner and outer which they are on about.
[12:28] <Laurenceb> yeah
[12:29] <Laurenceb> but they are using 300 ohm ribbon instead of the plain wire that moonraker suggest
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[12:30] <GW8RAK> Looking at the picture on page 3, the two driven elements look very much like a pair of slim jims on their side. with the capacitor being across the opening in the slim jim.
[12:30] <Laurenceb> wonder why they drive the front element
[12:31] <Laurenceb> guess they need the right sign phase lag
[12:31] <Laurenceb> hmf this is going to be fun.. or not
[12:31] <GW8RAK> With the twist in the ribbon feeder, that will feed antiphase to the reflector element with the stub on it.
[12:32] <Laurenceb> yeah, moonraker supplied some black insulated wire for that
[12:32] <Darkside> ZL special wut
[12:32] <Darkside> my dad has those for 2m
[12:32] <Laurenceb> but it wont be impedance matched... odd
[12:32] <Laurenceb> still cant work out how ill tune it
[12:33] <GW8RAK> Presumably by trimming the capacitor coax until low SWR?
[12:33] <Laurenceb> guess i could use my icom with the agc off
[12:33] <Laurenceb> i dont have a tx
[12:34] <GW8RAK> Can't you feed a NTX2 into it and make up a bridge circuit as per a noise bridge?
[12:34] <Laurenceb> probably... yeah
[12:34] <GW8RAK> Point it at a local repeater?
[12:34] <Laurenceb> i know
[12:34] <GW8RAK> But that assumes there is anyone on the local 70cm repeater
[12:34] <Laurenceb> put it into my sdr and look at snr
[12:35] <Laurenceb> for a ntx2 txing some way away
[12:35] <GW8RAK> That would do it.
[12:35] <Laurenceb> so - why the coax capacitor?
[12:35] <Laurenceb> surely a trimpot is more sensible
[12:35] <Laurenceb> so you can tx with high voltages?
[12:35] <GW8RAK> It's a cheap high voltage capacitor.
[12:36] <Laurenceb> yeah
[12:36] <Laurenceb> not relevant to me :D
[12:36] <Laurenceb> so ill get a proper trimpot
[12:36] <GW8RAK> Since you are not transmitting, that could be the easier option.
[12:37] <GW8RAK> I've tried trimming coax to length and it's not easy.
[12:37] <Laurenceb> im wondering if the feed between the two elements helps to be 300 ohm?
[12:39] <GW8RAK> A folded dipole has about a 277 ohm feed impedance. When you connect two of them in parallel, that gives you about 138 ohms feed impedance. The parallel stub is used to bring the feed impedance down to around 50 ohms for your 50 ohm coax. That stub is usually connected to the rear dipole and is often allowed to hang down vertically.
[12:39] <GW8RAK> Not my words. Just found it.
[12:40] <Laurenceb> thanks
[12:40] <GW8RAK> There's quite a bit on the feed here http://forums.qrz.com/showthread.php?t=178841
[12:40] <Laurenceb> what a stub?
[12:40] <eroomde> where you bash your toe into a door frame
[12:40] <eroomde> I learnt that on my M0 exam
[12:41] Action: eroomde gets back in his box
[12:41] <Laurenceb> lol
[12:41] <Laurenceb> *whats
[12:41] <jonsowman> hi eroomde
[12:41] <eroomde> hi jonsowman
[12:42] <jonsowman> how are you
[12:42] <Laurenceb> the stub is the capacitor thingy?
[12:42] <eroomde> well. attempting to escape the country but plans delayed by gatwick's closure
[12:43] <eroomde> so I'm baking instead
[12:43] <GW8RAK> That is the U shaped tubing between the open ends on the rear elements.
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[12:43] <eroomde> jonsowman: today will be the first day I make bread with my newly born sourdough starter
[12:43] <jonsowman> nice :SD
[12:43] <jonsowman> * :D
[12:44] <eroomde> never made a sourdough before. m excited!
[12:44] <jonsowman> hehe
[12:44] <jonsowman> where are you off to next?
[12:45] <Laurenceb> GW8RAK: theres no stub on the zl-special
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[12:46] <eroomde> jonsowman: berlin
[12:46] <eroomde> which is about as cold as norway at the moment, apparently
[12:46] <eroomde> nice
[12:46] <Laurenceb> -9C this morning in Derby
[12:46] <jonsowman> oh yes I remember you saying
[12:48] <Laurenceb> GW8RAK: i think i kind of understand the idea now, you drive two folded dipoles and a capacitor in parallel, in the hope that itll give 50 ohm impedance, and you phase lag the folded dipoles and stick one behind the other, to direct the radiation
[12:48] <Laurenceb> so the feed to the back dipole ideally needs to be impedanc ematched to 277ohm
[12:49] <Laurenceb> or 293ohm according to wikipedia
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[12:55] <GW8RAK> Yes, I think that is about right. Interestingly, I wonder if there is any directing of the radiation from the two folded dipoles and whether it doesn't all come from the front directors.
[12:55] <Darkside> oh man
[12:56] <Darkside> how yagis work is so awesome
[12:56] <Darkside> sympathetic resonance
[12:56] <GW8RAK> Ignoring the front directors if you just had two antiphase folded dipoles, would the direction flip from one direction to another, or average out to be omnidirectional.
[12:56] <Darkside> wait no
[12:57] <Darkside> parasitic array
[12:57] <Darkside> i derived this once..
[12:57] <GW8RAK> Adding the front directors could "draw" the radiation away from the driven elements and in the intended direction?
[12:58] <Laurenceb> GW8RAK: if you have two folded dipoles seperated with a phase lag, its going to radiate in one direction
[12:58] <Laurenceb> so you have 3dB or more gain from the two folded dipoles, then the elements add to that
[12:59] <Laurenceb> i still dont understand how it matches to 50 ohm
[12:59] <GW8RAK> Yes, because you are not feeding them equally; the flaw in my arguement.
[13:00] <GW8RAK> That is the role of the stub according the earlier article
[13:00] <Laurenceb> some hams are saying constructing folded dipoles from tube changes the impedance :-/
[13:00] <Laurenceb> cant see how that happens
[13:00] <GW8RAK> When looking at aerials, it is always worth remembering that you can pay £40 for a yagi and £400. I think there are a lot of assumptions and "if it works, it's good enough".
[13:01] <GW8RAK> Detailed science tends to get in the way.
[13:02] <Laurenceb> well im adding a lna to the antenni and i want to get the best possible performance at the lowest cost :P
[13:02] <GW8RAK> Cebik at cebik.com did a lot of aerial analysis. Have at look at his site. Although it needs a login, it is free.
[13:02] <GW8RAK> bbl
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[13:37] <Laurenceb> SpeedEvil: your electroformed engine idea- what about 3D printing
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[13:52] <SpeedEvil> Smoothness is a problem
[13:54] <GW8RAK> Not that is a cryptic comment
[13:55] <GW8RAK> Now, not Not
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[14:05] <m1x10> Hi all
[14:05] Action: m1x10 suffers :)
[14:06] <GW8RAK> Laurenceb - I was just reading the ZL special article by Frank Judd and there area some strange things in it. The photograph shows two elements to each of the driven ones.
[14:06] <GW8RAK> And the driven elements are dipoles, not folded ones.
[14:07] <Laurenceb> hmm yeah
[14:07] <Laurenceb> guess thats still the same principle
[14:07] <Laurenceb> i guess the weird parasitics from the wire design moonraker suggest are canclled by the tuning capacitor
[14:08] <Laurenceb> so it doesnt matter that much that you dont have a perfect impedance matched feed
[14:08] <GW8RAK> Oh, looking at the picture on page 3, it must be that he is using two elements in parallel for each feed to presumably give the equivalent of a wider tube and wide bandwidth
[14:09] <Laurenceb> im just going to use the design moonraker suggest, but with a tuning cap
[14:09] <Laurenceb> and an lna
[14:10] <GW8RAK> You should be able to find the capacitance of the coax if you know the type of coax
[14:11] <Laurenceb> yeah - looks like about 10pf or so
[14:11] <Laurenceb> for the 90mm of RG-58 people have suggested works
[14:11] <Laurenceb> http://www.bbc.co.uk/news/world-us-canada-11923766
[14:11] <Laurenceb> ^ lol @ anti snake venom plant
[14:12] <Laurenceb> theres obviously a rick from snakes on a plane
[14:12] <Laurenceb> *risk
[14:12] <GW8RAK> I saw that film title. What was it about?
[14:12] <Laurenceb> lol
[14:12] <NigeyS> cold cold cold sodding cold! :@
[14:12] <GW8RAK> The most obvious film title ever.
[14:13] <Laurenceb> NigeyS: -13C this morning
[14:13] <NigeyS> i can believe it to, i was walking to work at 4am lol !
[14:14] <GW8RAK> Work at 4am?
[14:15] <NigeyS> yeah, was helping my dad out, works for biffa, they do some crazy shifts!
[14:19] <NigeyS> lol @ rapidswitch, £100 to fit my server with an external drive for backups .. no ta !
[14:21] <fsphil> holy crap, we just got more snow in the last hour than we've had all week
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[14:22] <NigeyS> lol
[14:22] <NigeyS> keep it there ffs! :p
[14:22] <fsphil> heading your way I think :p muhaha
[14:22] <fsphil> worst thing is that it had mostly melted
[14:22] <NigeyS> the fog was the nasty thing this morning
[14:22] <NigeyS> couldnt see 10ft in front of me
[14:22] <fsphil> oh yea, freezing fog too
[14:23] <NigeyS> yups :(
[14:24] <Laurenceb> oh no more snow ?!
[14:24] <fsphil> lots more
[14:24] <fsphil> in NI at least
[14:24] <fsphil> and scotland too I think
[14:26] <NigeyS> we really dont tend to get much down here
[14:26] <NigeyS> and if we do it rarely settles
[14:26] <NigeyS> Laurenceb you ever dabbled in radio astronomy ?
[14:27] <SpeedEvil> It's allegedly going back positive after thursday here
[14:27] <SpeedEvil> and melting
[14:27] <Laurenceb> nope
[14:27] <Laurenceb> Q. How does a chemist integrate a curve?
[14:27] <Laurenceb> A. They cut out the plot and weigh the piece of paper. Then compare this with the weight of a piece of paper of known area.
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[14:28] <GW8RAK> I actually remember doing that.
[14:28] <GW8RAK> Once only though
[14:28] <NigeyS> SpeedEvil, looks like come thursday we're back up to sensible temps, 6 / 7 celcius
[14:28] <GW8RAK> Whatever happened to paper chart recorders
[14:29] <NigeyS> Laurenceb, i was thinking of a mesh based telescope on my back lawn .. could work..lol
[14:29] <Laurenceb> GW8RAK: we had them when i worked at blue circle cement
[14:30] <GW8RAK> We did it at University and once afterwards. Then we got an HP integrator.
[14:30] <Laurenceb> in the james bond villain style control room XD
[14:31] <Laurenceb> with bbc model Bs and econet
[14:31] <GW8RAK> We had to transfer data from the integrator to the University mainframe and had a box made up with 256K of RAM in it. I think it cost over £1000.
[14:31] <Laurenceb> http://www.geograph.org.uk/photo/224929
[14:32] <GW8RAK> That seemed like a lot of tech at the time.
[14:32] <GW8RAK> Then went to work for Philips and had integrators on every instrument.
[14:32] <GW8RAK> A good job.
[14:36] <Laurenceb> wish i could find some photos from someone whos actually made a moonraker zl-special work
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[14:39] <fsphil> are the instructions in english at least?
[14:41] <Laurenceb> yes, but they dont make sense, and assume you have a swr meter
[14:41] <fsphil> ah
[14:41] <fsphil> hate that
[14:42] <Laurenceb> connect center of coax to tag on capacitor and capacitor to brass terminal. connect braid of coax to other brass terminal. adjust capacitor for best swr
[14:42] <Laurenceb> thats it
[14:42] <Laurenceb> theres no brass tags or capacitors to be seen :P
[14:43] <Laurenceb> http://www.m3oyq.com/wp-content/uploads/2008/11/7-element-zl-special-on-rotator.jpg
[14:44] <Laurenceb> thats the best i can find
[14:46] <eroomde> sorry if i've missed the conversation, but that's the logic of two folded elements?
[14:47] <Laurenceb> so you can phase lag one
[14:47] <Laurenceb> then you get constructive interference in one direction
[14:47] <Laurenceb> im suprised by the sloppyness of construction in that photo
[14:47] <Laurenceb> but it looks like it might be using 300ohm line? cant quite see from the pic
[14:49] <eroomde> Laurenceb: is that more efficient than using a reflecting element?
[14:50] <Laurenceb> yes
[14:51] <Laurenceb> if you work out how to do the matching properly, apparently this 7 element ant can get 14dBi gain
[14:53] <Laurenceb> hmm from looking at that photos, i think you can see the stub/coax capacitor poking out of the forward folded element, but the feed between the two driven elements seems to be wire glue gunned together
[14:54] <Laurenceb> very odd
[14:54] <SpeedEvil> [
[14:54] <SpeedEvil> _Ridiculously_ fluffy snow today
[14:55] <eroomde> Laurenceb: do these yagi's have a name?
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[14:55] <Laurenceb> zl-special
[14:56] <Laurenceb> http://www.moonraker.eu/ZL-Special-Yagi-Antenna
[14:56] <Laurenceb> i have the cheapscate one (for obvious reasons)
[14:59] <GW8RAK> Laurenceb - does the Moonraker one use folded dipoles like the recent photo?
[14:59] <GW8RAK> The Judd article, unless I'm reading it wrong, does not use folded dipoles.
[14:59] <eroomde> Laurenceb: ok thanks for bringing me up to speed
[14:59] <Laurenceb> that photo is the moonraker ant
[15:00] <Laurenceb> - 145mhz version, but its just a scaled up copy of whats on my desk
[15:00] <GW8RAK> I wouldn't want to run the feed coax up and over the rear element like that. Why not just drop it downwards?
[15:00] <GW8RAK> And then tie wrap it to the mast
[15:00] <SpeedEvil> http://www.flickr.com/photos/14560445@N08/5237662575/ Pretty.
[15:03] <Laurenceb> ill probably run the coax through the main square alu bar
[15:03] <Laurenceb> wow thats a fair bit of snow
[15:05] <SpeedEvil> The top 6" or so is actually damn near aerogel
[15:05] <SpeedEvil> It's maybe something like 5mm of actual water, if that.
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[16:11] <Laurenceb> http://www.hamuniverse.com/gi6jpozl-special.pdf
[16:11] <Laurenceb> looks like it needs to be done with 300 ohm ribbon
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[16:19] <timbobel> oh hi
[16:19] <SpeedEvil> hi
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[16:41] <fsphil> my launch this weekend is looking unlikely atm -- all predictions have it splashing down
[16:42] <SpeedEvil> :/
[16:43] <fsphil> with a slow ascent it might just make wales, but not with a comfortable enough margin
[16:50] <LazyLeopard> Ugh. Not a lot of good if recovery's the aim...
[16:52] <fsphil> indeed
[16:53] <fsphil> but if not this weekend I'll definitely launch next weekend -- this is my second notam and I'm not wasting it :)
[16:54] <LazyLeopard> What's your payload?
[16:55] <fsphil> Canon A560, uart camera + the usual avr + gps bits
[16:57] <fsphil> not a horribly expensive payload, but I don't want to take any big risks with it
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[17:12] <fsphil> timbobel, https://github.com/fsphil/dl-fldigi/commit/57f07f419d36cf9fd677db132ebc3c4e390e616a
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[19:01] <laurence_> hi
[19:01] Nick change: laurence_ -> Laurenceb_
[19:01] <Laurenceb_> freaking zl-special antenna
[19:01] <Laurenceb_> how do they work
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[19:18] <Laurenceb_> looks like 300ohm ribbon has to be used at any rate - looks like moonrakers instructions might be nonsense
[19:20] <Laurenceb_> SpeedEvil: your electroformed nozzle idea - why does it all have to use metal, why not electroform only the inner surface and have a composite outer layer
[19:33] <SpeedEvil> regerentative
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[19:36] <Laurenceb_> huh
[19:38] <SpeedEvil> It was designed to be an electroformed regeneratively cooled engine
[19:38] <SpeedEvil> Electroforming the whole thing means that if you can pull it off, a lot of the seals go away.
[19:40] <SpeedEvil> Also - thermal compatibilities at the interfaces
[19:40] <Laurenceb_> yeah i guess the fuel gets hot
[19:41] <SpeedEvil> I was surprised that the density of snow today was .05
[19:41] <Laurenceb_> copper isnt very strong :-/
[19:42] <SpeedEvil> Not really
[19:43] <SpeedEvil> Copper/carbon seems well studied
[19:43] <SpeedEvil> and some tests of electroforming it worked well
[19:43] <SpeedEvil> Also decreases density
[19:44] <Laurenceb_> yeah - does the stiffness work?
[19:44] <Laurenceb_> as in stiffness of CF versus copper
[19:45] <SpeedEvil> From memory, yes.
[19:45] <SpeedEvil> It's a while back though
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[19:45] <Laurenceb_> interesting
[19:46] <Laurenceb_> guess its still a rather complex operation to electroform the entire thing...
[19:47] <SpeedEvil> Quite, yes.
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[19:48] <SpeedEvil> I was starting off with a spun copper form.
[19:48] <Laurenceb_> surely thats easy to form
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[19:48] <Laurenceb_> the tricky bit is the channels
[19:48] <SpeedEvil> Then 'gluing' wax channels onto it.
[19:49] <SpeedEvil> Then electroforming over the top of these.
[19:49] <SpeedEvil> And then melting out
[19:51] <Laurenceb_> why not - inner conductive wax form, electroplate onto that, then a two part rubber jig for casting the wax channels over it
[19:51] <Laurenceb_> then overwrap with cf and further electroplating
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[19:56] <Laurenceb_> the alternative is of course a jig to bend + squash thinwall brass tube
[20:05] <SpeedEvil> spinning is a nice way to make the initial form
[20:05] <SpeedEvil> yes, that may work too
[20:05] <Laurenceb_> more work if you want to make more than 1, and heavier
[20:06] <Laurenceb_> i dont see how you can do the channels without ending up with some walls that are twice as thick as they need to be
[20:09] <Laurenceb_> theres alwasy soldering
[20:11] <SpeedEvil> I was also considering dipping in wax, and then carving off slots in the waz
[20:11] <SpeedEvil> x
[20:11] <SpeedEvil> using some sort of machine
[20:12] <Laurenceb_> have to be careful the front of the slot doesnt fill with copper first
[20:12] <Laurenceb_> and block the back
[20:12] <Laurenceb_> i think you could do clever things with varnish
[20:14] <SpeedEvil> yeah
[20:14] <Laurenceb_> 1) electroform copper onto inner wax form
[20:14] <Laurenceb_> 2) 2 piece rubber former goes round it to cast conductive wax channels
[20:14] <SpeedEvil> The hard part in many ways isn't the process or the design.
[20:14] <SpeedEvil> It's getting it so it's repeatable
[20:15] <Laurenceb_> 3) second rubber former or maybe some sort of masking off most of the parts of the inner copper that are still exposed
[20:16] <SpeedEvil> hmm
[20:16] <Laurenceb_> 4) spray/immerse with varnish to cover everything apart from sides of wax channels
[20:16] <Laurenceb_> 5) electroplate from outside
[20:16] <Laurenceb_> no 5) overwrap with CF
[20:16] <SpeedEvil> It's a samn shame you can't electroplate Al
[20:17] <SpeedEvil> damn
[20:17] <Laurenceb_> 6) electroplate from outside
[20:17] <SpeedEvil> I also wondered about something sneaky.
[20:17] <Laurenceb_> 7) melt all the wax
[20:17] <Laurenceb_> finished :D
[20:18] <SpeedEvil> Make the concentric channels and the three coaxial pipes all as simple straight pipes.
[20:18] <SpeedEvil> Now fill the channels with something, and spin it
[20:18] <SpeedEvil> To make it into a chamber and throat
[20:18] <SpeedEvil> and nozzle
[20:18] <Laurenceb_> three coaxial pipes?
[20:19] <Laurenceb_> i doubt you could keep the structure intact throughout all that spinning
[20:19] <SpeedEvil> yes.
[20:20] <SpeedEvil> I somewhat doubt it too.
[20:20] <SpeedEvil> But it would be nice in some ways.
[20:20] <Laurenceb_> down to -13C again, wonderful
[20:21] <SpeedEvil> Actually, or forecast?
[20:21] <Laurenceb_> hmm you could work in the other direction
[20:21] <Laurenceb_> actually
[20:21] <Laurenceb_> -14 now
[20:23] <Laurenceb_> conductive wax cylinder with radial CF sheets, then lathe out the middle to form the nozzle
[20:23] <Laurenceb_> electroplate onto the inside, then melt off the wax and cast nonconductive wax in the center
[20:24] <Laurenceb_> lathe off the outside leaving a few mm or whatever of the CF sticking out
[20:24] <SpeedEvil> hmm
[20:24] <Laurenceb_> melt the wax off the outside, overwrap and electroplate the outside
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[20:25] <Laurenceb_> yes the wax on the inside might melt as well - youd need to work that one out a bit better
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[20:26] <Laurenceb_> it wastes a lot of CF fabric, but its quite cheap stuff now
[20:27] <SpeedEvil> I was wondering a bit ago how to make Al/Cf composite
[20:28] <SpeedEvil> I think it's quite possible - draw fluxed CF tow over several rollers under heated Al.
[20:28] <SpeedEvil> And then through an orifice.
[20:29] Action: Laurenceb_ tried to remember the aluminium/NaOH reaction
[20:29] <Laurenceb_> cant you get aluminium salts or something...
[20:30] <SpeedEvil> Naah - the problem is you need to do it fast, in under several seconds, or it degrades
[20:31] <SpeedEvil> http://resources.metapress.com/pdf-preview.axd?code=p67510w64525h060&size=largest
[20:34] <Laurenceb_> interesting
[20:34] <Laurenceb_> itd be fun to try some of this, all the kit is cheapish
[20:34] <Laurenceb_> apart from a decent lathe
[20:35] <SpeedEvil> yup
[20:36] <Laurenceb_> and somewhere to put it... :(
[20:36] <SpeedEvil> A balmy -8C here.
[20:36] <SpeedEvil> I'm still surprised my freezer can hit -45
[20:37] <Laurenceb_> theres massive ice crystals ontop of the snow - ~3cm diameter
[20:37] <SpeedEvil> See my earlier pic? Recent snow was stupidly fluffy.
[20:37] <Laurenceb_> yeah
[20:40] <SpeedEvil> That reminds me.
[20:40] Action: SpeedEvil turns on taps a bit.
[20:44] <Laurenceb_> wonder how regen emgines scale
[20:45] <Laurenceb_> http://www.pro38.com/products/pro38/motor/MotorData.php?prodid=266H125-12A
[20:45] <Laurenceb_> im suprised hw well the small solids perform
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[20:51] <timbobel> sphil are you here
[20:51] <NigeyS> hey tim
[20:51] <timbobel> hello hello
[20:51] Action: fsphil waves
[20:52] <timbobel> so can someone put HoHoHo in the tracker already for 19/12?
[20:52] <timbobel> aaaaah fsphil i get it
[20:53] <timbobel> what you have done; if you select baudot, it just interprets the character differently!?
[20:53] <fsphil> exactly
[20:53] <fsphil> nothing else needs to be changed
[20:53] <timbobel> 3.20.16 is current version right
[20:53] <timbobel> that's pretty smart..
[20:53] <fsphil> yea it's not in the current version
[20:53] <fsphil> you'll need to add it yourself for now
[20:53] <timbobel> thought so
[20:53] <timbobel> yeah yeah
[20:54] <fsphil> but it's a one-liner, simple
[20:54] <fsphil> just means that anyone else tracking will have to add the line too
[20:54] <fsphil> until the next release
[20:54] <timbobel> surely
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[21:45] <SAIDias_> what would be the technical term for the lines that connect the payload to the parachute & balloon?
[21:46] Nick change: SAIDias_ -> W0OTM
[21:46] <SpeedEvil> rigging?
[21:46] <W0OTM> ok, that will work
[21:46] <W0OTM> :)
[21:46] <W0OTM> im writing an mag article
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[21:49] <W0OTM> how do you define necklift?
[21:49] <Randomskk> the force the balloon neck has upwards, before any payload is attached
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[21:50] <Randomskk> in other words the total lift of the gas minus the weight of the balloon itslf
[21:50] <Randomskk> itself*
[21:53] <W0OTM> ok, so "Neck lift is the force the balloon neck has upwards, before any payload is attached. The difference between launch weight and neck lift, determines the ascent rate. "
[21:54] <Randomskk> yes
[21:54] <W0OTM> ok, thx
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[22:30] <Laurenceb_> http://www.theregister.co.uk/2010/12/06/dragon_launch/
[22:30] <Laurenceb_> ^ worth a watch
[22:31] <natrium42> tomorrow? oooh
[22:32] <SpeedEvil> Yes.
[22:32] Action: SpeedEvil has _everything_ crossed.
[22:33] <russss> I think they put it back to Thursday
[22:33] <russss> http://twitter.com/#!/SpaceXer/status/11856498544091136
[22:34] <russss> although http://twitter.com/#!/NASA/status/11884309283606528
[22:36] <Laurenceb_> eww twitter
[22:36] Action: Laurenceb_ stays away from such things
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[22:49] <Laurenceb_> SpeedEvil: why not use something like woods metal for your engine forming idea
[22:54] <Laurenceb_> bbl
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[23:04] <Laurenceb_> fields metal even
[23:08] <SpeedEvil> You mean spinning the pre-formed engine wall
[23:08] <SpeedEvil> yes - that's sort of what I was thinking of
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[23:13] <russss> "SpaceX now says the Falcon 9 rocket launch for NASA's COTS program is no earlier than Wednesday. Earlier it was estimated to be Thursday."
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[23:32] Nick change: DagoRed -> kd0mto
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[00:00] --- Tue Dec 7 2010