[00:15] jgw (n=jgw@unaffiliated/jgw) joined #highaltitude. [00:40] down - phew [00:40] night [00:40] rocketboyV1 (n=steve@217.47.75.147) left irc: "Leaving" [00:46] phatmonkey (n=ben@81.2.121.150) joined #highaltitude. [00:49] phatmonkey (n=ben@81.2.121.150) left irc: Client Quit [01:07] edmoore (n=edmoore@88.212.167.121) joined #highaltitude. [01:26] Nick change: MetaMorfoziS -> metaway [01:40] edmoore (n=edmoore@88.212.167.121) left irc: [02:13] Tigga (n=chatzill@pc-111-221-234.magd.cam.ac.uk) left irc: Read error: 110 (Connection timed out) [05:33] borism (n=boris@195-50-207-118-dsl.krw.estpak.ee) joined #highaltitude. [05:43] akawaka (n=akawaka@external.treyarch.com) left irc: Read error: 110 (Connection timed out) [06:15] akawaka (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) joined #highaltitude. [08:20] akawaka (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) left irc: Read error: 110 (Connection timed out) [08:28] akawaka (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) joined #highaltitude. [09:03] akawaka (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) left irc: Read error: 110 (Connection timed out) [09:33] jcoxon (n=jcoxon@host86-142-170-54.range86-142.btcentralplus.com) joined #highaltitude. [09:36] jcoxon (n=jcoxon@host86-142-170-54.range86-142.btcentralplus.com) left irc: Client Quit [09:40] Akadecca (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) joined #highaltitude. [10:45] Akadecca (n=akawaka@cpe-76-173-152-142.socal.res.rr.com) left irc: Read error: 110 (Connection timed out) [10:50] jcoxon (n=jcoxon@host86-142-170-54.range86-142.btcentralplus.com) joined #highaltitude. [11:01] Laurenceb (n=laurence@host81-157-248-24.range81-157.btcentralplus.com) joined #highaltitude. [11:08] flowolf (n=flowolf@host153-237-dynamic.8-79-r.retail.telecomitalia.it) joined #highaltitude. [11:25] Laurenceb (n=laurence@host81-157-248-24.range81-157.btcentralplus.com) left irc: Remote closed the connection [11:35] edmoore (n=edmoore@88.212.167.121) joined #highaltitude. [11:36] morning edmoore [11:36] hi jcoxon [11:36] how's it going? [11:36] okay, [11:36] just found out that cocoamodem only decodes baudot and not ascii [11:37] yes [11:37] well rtty is baudot [11:37] yeah but steve sends it ascii [11:37] oh righty [11:37] time to send a grovelmail :) [11:37] i assume as its easier to link into serial ports etc [11:38] well i can get hold of the code for cocoamodem [11:38] so in theory i could add the feature in [11:38] or i could persuade rocketboy to change his transmission to baudot :-p [11:40] http://news.bbc.co.uk/1/hi/technology/7314362.stm [11:40] still, not really applicable to us [11:40] yeah i saw [11:41] well we could fly close to an aeroplane and get reception :-p [11:41] I wonder what the caa would say [11:41] there might be a little upset [11:41] if we fired sucking harpoons onto passing planes [11:41] Tigga_ (n=chatzill@pc-111-221-234.magd.cam.ac.uk) joined #highaltitude. [11:41] Nick change: Tigga_ -> Tigga [11:41] haha [11:41] that could let us do transatlantic the other way!!! [11:41] piggyback [11:42] oh edmoore, i'm setting up my cupboard server [11:42] would you like an account to play with? [11:42] a what server? [11:42] oh god yes! [11:42] its in my cupboard [11:42] I would love some webspace proper [11:42] lol [11:42] what kinda deal can you offer me jimbob? :p [11:43] well its going to go through our home broadband so it'll be a dynamic dns thingy whatsit [11:43] also you'll get a nice linux shell account to play with [11:43] do you have a decent upload speed? [11:44] hmmm only 448kbps [11:44] 6720kbps down though [11:44] that's fine tho for browsing [11:44] oh and its unlimited download [11:44] oooo [11:45] well I'd love an account, yes [11:45] thankyouverymuch [11:45] mc- (n=mfcastle@cpc4-glfd1-0-0-cust538.glfd.cable.ntl.com) joined #highaltitude. [11:45] okay cool, well i've set it up but am having some network issues - damn wireless cards - tempted to run a cable [11:49] Am reading up on mars descents [11:49] they have this really interesting problem when it comes to landing anything larger than what they've landed so far [11:49] in as far as - there's too much atmosphere to do a sort of lunar style landing with rocket decelleration [11:50] but not enough to do the current heat shield then parachute that they do now for small buggies [11:50] it's a pretty big problem for landing 1tonne + [11:50] they'd be look at 20 tonnes for manned stuff [11:51] ed, I just met your fearless admin person at Charterhouse [11:51] oh blimey [11:51] jen is organizer supreme [11:52] she doesn't know if you will coming to the conf [11:52] me neither! [11:53] if Laurence is around, tell him, I've managed to route his PCB [11:53] I helped the autorouter, to be precise [11:54] willdo [11:54] don't bother with manual routing, I'm converted to autorouters now [11:55] I also spoke to Will P from xprize [11:56] oh? [11:56] have you converted him/ [11:56] nearly, he could see my logic [11:57] he suggested I go to the Strasbourg conf in May [11:59] but I don't think I have time [11:59] would your new employer pay for your expenses to attend? [12:02] Laurenceb (n=Laurence@host81-157-248-24.range81-157.btcentralplus.com) joined #highaltitude. [12:04] Action: Laurenceb is running freerouting.net [12:04] just sent you an email [12:04] ok [12:04] all done [12:04] I've switched to XP and got it running [12:05] wow cool [12:05] had to space out some of the components, then it routed fairly quick [12:05] right [12:06] I'm impressed with the routing [12:06] me too [12:09] ok, I'm just looking at the .brd [12:10] looks like it can be tweaked a bit, and I'd like to try adding a groundplane [12:11] autorouting is almost fun now [12:12] hehe [12:13] it might take a bit of tweaking to meet pcbcarts design rules [12:13] mc- (n=mfcastle@cpc4-glfd1-0-0-cust538.glfd.cable.ntl.com) left irc: [12:27] Nick change: metaway -> MetaMorfoziS [12:50] edmoore (n=edmoore@88.212.167.121) left irc: [13:07] zeusbot_ (n=zeusbot2@host86-142-170-54.range86-142.btcentralplus.com) joined #highaltitude. [13:08] test [13:13] hello world [13:13] hello Laurenceb [13:14] hello jcoxon [13:14] what are you testing? [13:15] i'm planning on moving zeusbot to my home server i just set up, was testing that it was logging [13:15] cool [13:16] i'm still working out the whole logistics and whether it is work it [13:16] worth* [13:26] edmoore (n=edmoore@88.212.167.121) joined #highaltitude. [13:52] hey edmoore [13:52] hi [13:52] Action: Laurenceb has a routed board [13:52] ooooh [13:52] nice [13:52] thanx to some help from mc- [13:52] pics? [13:52] needs a little more work... [13:52] mc- used freerouting on it [13:52] its very impressive [13:53] better than the eagle router by quite a bit [13:53] but it needs a bit of hand optimising [13:53] will probably end up around 35x45mm [13:55] impressive [14:15] MetaMorfoziS (n=avr@3e70d272.adsl.enternet.hu) left irc: "byall" [14:24] http://wiki.ukhas.org.uk/projects:ukhas_glider_project:flight_computer [14:27] needs a bit more work to meet the drc [14:32] mc- (n=mfcastle@cpc4-glfd1-0-0-cust538.glfd.cable.ntl.com) joined #highaltitude. [14:35] hey there mc- [14:35] how's it going? [14:35] just working on fine tuning it - http://wiki.ukhas.org.uk/projects:ukhas_glider_project:flight_computer [14:36] looks good, and only slightly larger than your first layout [14:36] yes, should end up 35x45 mm [14:37] imagine trying to route it manually.. [14:37] hehe [14:37] thanx for all the help :P [14:37] zeusbot_ (n=zeusbot2@host86-142-170-54.range86-142.btcentralplus.com) left irc: Remote closed the connection [14:38] zeusbot_ (n=zeusbot2@host86-142-170-54.range86-142.btcentralplus.com) joined #highaltitude. [14:38] I wanted to understand autorouters, as I can't face manual routing [14:39] by the way, have a look at olimex.com for pcbs [14:40] I'm thinking of pcbcart.com [14:40] I've used batchpcb before, but they are slow and lost one delivery in the post [14:41] what did pcbcart.com quote? Olimex have a fixed price for a 100x160mm area [14:41] I think shipping charges from China are high? [14:43] not really [14:44] pcbcart have a tooling cost, which is annoying [14:44] but they charge per area, and have a good election of materials [14:44] selection* [14:44] batchpcb just have FR4 [14:45] olimex shipping is around $5 for standard delivery [14:45] the per area cost is really cheap, a few $ for these [14:45] but how much for one panel? [14:46] I think it's around $30 total [14:46] right [14:46] ok, I was under the impression it was more [14:47] might try it, the problem is they can only do 10mil tracks [14:47] batchpcb go down to 8, and pcbcart even smaller [14:48] oh well, I'll try a drc with everythnig at 10mil [14:49] oh god: 300 errors [14:50] it you can fit it into 33x50mm, then you can get 9 PCBs on a panel for $30 [14:50] Action: Laurenceb checks olimex [14:50] you'll need to re-route with larger spacing [14:54] ok... olimex's rules are a bit complex... batchpcb automates it all [14:54] I think I've entered it all ok, got 240 errors now [14:56] lol, looks like there were rounding errors with my holes, as I was working in mm [15:05] Laurenceb: you can have 8mil spacing [15:05] just takes longer [15:09] from the site it looks like 8mil [15:09] for everything :/ [15:10] and their via clearances are crazy [15:13] oh I see [15:13] why bother :( [15:14] Action: Laurenceb heads off to pcbcart [15:20] pcbcart is £23 + postage [15:20] for 8 days [15:23] pcbs are a pain :( [15:32] jgw (n=jgw@unaffiliated/jgw) left irc: Remote closed the connection [15:48] well I'm down to 80 errors [15:50] jcoxon (n=jcoxon@host86-142-170-54.range86-142.btcentralplus.com) left irc: "Leaving" [15:56] MetaMorfoziS (n=avr@3e70d272.adsl.enternet.hu) joined #highaltitude. [16:02] can you adjust the clearances in the autorouter? [16:02] then you don't have to manually reroute? [16:02] how many pcbs do you get from pcbcart for 23? [16:10] just one [16:10] but you could get more for about £6 each [16:11] going down to less for 5+, 10+ ect [16:13] so olimex is good value, but a bit more difficult to meet their clearances etc [16:17] there's a clearance matrix in freerouter [16:18] but I can't work out the units [16:19] I'm hand routing now [16:20] down to 41 errors using olimex's specs [16:20] why not reroute with the autorouter? [16:21] hmm [16:22] I prefer to do it like this, hand routing can be better [16:24] I think it almost always is in projects of this size and complexity [16:24] (or lack thereof) [16:25] I've worked out the freerouter clearances, just trying rerouting, so I can use olimex on my pcbs in future. [16:28] cool [16:28] down to 25 errors :P [16:31] flowolf (n=flowolf@host153-237-dynamic.8-79-r.retail.telecomitalia.it) left irc: "Leaving" [16:33] MetaMorfoziS (n=avr@3e70d272.adsl.enternet.hu) left irc: "Most akkor mit csinalt aki miert lepett ki?" [16:40] brb [16:43] mc- (n=mfcastle@cpc4-glfd1-0-0-cust538.glfd.cable.ntl.com) left irc: Read error: 110 (Connection timed out) [16:49] phatmonkey (n=ben@81.2.121.150) joined #highaltitude. [16:54] done, no errors XD [16:56] http://wiki.ukhas.org.uk/projects:ukhas_glider_project:flight_computer [16:58] just needs a silkscreen now [17:30] Action: natrium42 punches Laurenceb for not using 45 and 90 degree angles only [17:31] hehe [17:31] its more organic [17:32] my components aren't at weird angles this time :P [17:33] :P [17:33] if I'd designed it completely by hand I'd have done that as well [17:34] the pcb fabs can do any angle, so you might as well take advantage of that IMO [17:37] jcoxon (n=jcoxon@host86-142-170-54.range86-142.btcentralplus.com) joined #highaltitude. [17:40] Laurenceb, this router looks pretty awesome --> http://www.reltronics.com.au/topor.php [17:40] and is in line with your design practice :) [17:41] jatkins (n=jatkins@79-73-109-74.dynamic.dsl.as9105.com) joined #highaltitude. [17:42] haha sweet [17:42] love the animation [17:42] :) [17:42] i have to try this router sometime [17:43] it's free for a certain number of layers, i believe [17:45] yes, 8 layers, 125 nets [17:45] it looks amazing [17:46] I'd have to work out how to use it with eagle [17:46] i think you can'd use it with eagle unfortunately [17:46] i was planning to use it with protel [17:46] ah you can import dsn [17:46] ok, I have a brd to dsn convertor [17:48] cool [17:50] Hiena (n=Hiena@81.93.195.181.datatrans.hu) joined #highaltitude. [17:51] Good evening! [17:54] hmm "import error" [17:58] it isnt able to import my dsn file :( [18:00] so fustrating :( [18:00] MetaMorfoziS (n=avr@dsl54009F1F.pool.t-online.hu) joined #highaltitude. [18:01] jatkins (n=jatkins@79-73-109-74.dynamic.dsl.as9105.com) left irc: " HydraIRC -> http://www.hydrairc.com <- Now with extra fish!" [18:02] natrium42: can you try? [18:02] if you go to www.freerouting.net and get the ulp [18:04] MeTa (n=avr@dsl54009F1F.pool.t-online.hu) joined #highaltitude. [18:07] natrium42: any luck? can you try it? [18:14] akawaka (n=akawaka@external.treyarch.com) joined #highaltitude. [18:18] MetaMorfoziS (n=avr@dsl54009F1F.pool.t-online.hu) left irc: Connection timed out [18:20] anyone want to try this for me? [18:20] http://www.reltronics.com.au/topor.php [18:22] together with the brd to dsn ulp file from freerouting.net [18:55] jcoxon (n=jcoxon@host86-142-170-54.range86-142.btcentralplus.com) left irc: "Leaving" [19:22] Hiena (n=Hiena@81.93.195.181.datatrans.hu) left irc: "-=Alkoholmentes-sör és repülõgép-szimulátor, biztos út a guminõ felé=-" [19:33] edmoore (n=edmoore@88.212.167.121) left irc: [19:35] edmoore (n=edmoore@88.212.167.121) joined #highaltitude. [19:39] http://wiki.ukhas.org.uk/projects:ukhas_glider_project:flight_computer [19:39] ^ board is finished :P [19:40] MeTa (n=avr@dsl54009F1F.pool.t-online.hu) left irc: Read error: 104 (Connection reset by peer) [19:49] edmoore (n=edmoore@88.212.167.121) left irc: [19:55] nice [19:55] gonna go with a custom board next time [19:55] this full linux box is unweildy and underused [20:01] zeusbot_ (n=zeusbot2@host86-142-170-54.range86-142.btcentralplus.com) left irc: Read error: 104 (Connection reset by peer) [20:08] edmoore (n=edmoore@88.212.167.121) joined #highaltitude. [20:14] MetaMorfoziS (n=avr@3e70d272.adsl.enternet.hu) joined #highaltitude. [20:16] pcbcart are giving me an insane tooling cost now :( [20:18] looks like they aren't any good [20:19] just use gold phoenix [20:19] :P [20:21] but you need a big panel [20:22] MetaMorfoziS (n=avr@3e70d272.adsl.enternet.hu) left irc: Remote closed the connection [20:22] MetaMorfoziS (n=avr@3e70d272.adsl.enternet.hu) joined #highaltitude. [20:22] this is annoying [20:22] guess so [20:22] maybe somebody in here wants to make pcbs and you can combine? [20:22] maybe :P [20:23] I really want to avoid batchpcb, and olimex is rather poor [20:24] yeah, goldphoenix is pretty damn fast [20:24] maybe I should make a cnc machine for doing vias and things [20:24] you can pay extra for rush service [20:25] oh hang on... pcbcart likes nice sizes... [20:27] or maybe not... this is just stupid [20:27] Action: natrium42 likes good service and speed :P [20:29] phatmonkey (n=ben@81.2.121.150) left irc: [20:31] borism (n=boris@195-50-207-118-dsl.krw.estpak.ee) left irc: Client Quit [20:31] damnit looks like I'll have to use batchpcb [20:32] phatmonkey (n=ben@81.2.121.150) joined #highaltitude. [20:43] phatmonkey (n=ben@81.2.121.150) left irc: Read error: 104 (Connection reset by peer) [20:44] edmoore (n=edmoore@88.212.167.121) left irc: [20:44] arrgg I've forgotten how to use batchpcb [20:45] any batchpcb users? [20:53] nvm sorted it [21:08] RocketBoy_ (n=ubuntu@217.47.75.147) joined #highaltitude. [21:27] yansa (n=yans@host-89-167-37-237.pronet.lublin.pl) joined #highaltitude. [21:27] RocketBoy_ (n=ubuntu@217.47.75.147) left irc: "Ex-Chat" [21:37] edmoore (n=edmoore@88.212.167.121) joined #highaltitude. [21:42] I've sent the flight computer off to batchpcb [21:42] it meets their drc [21:43] I'll probably send off an order to batchpcb for a few boards, and also a fixed radio board [21:44] cool [21:44] should have them by July then [21:44] if anyone wants some boards feel free to let me know and we can save a bit on post [21:44] lol [21:44] yes [21:44] oh well I have exams [21:44] it usually takes 3 weeks [21:44] bbl [22:20] phatmonkey (n=ben@81.2.121.150) joined #highaltitude. [22:24] I need Laurence of Arabia [22:30] lol? [22:32] no seriously [22:33] I have a huge lump of cheddar cheese, some biscuits, and half a bottle of red wine [22:33] and I need a proper man film to consume it all with [22:44] RocketBoy_ (n=ubuntu@217.47.75.147) joined #highaltitude. [22:45] hi RocketBoy_ [22:45] Just read your email [22:45] hey ed [22:45] so what's your gut instinct on the direction to head in? [22:46] yeah its all a bit complex [22:46] instinct wise I guess HF packet radio [22:46] I tried to write down some stuff but got the point that I couldn't tell if it was just complicated and irreducible or I'd made an algebraic error [22:46] there is a lot of support about [22:47] what kind of number is HF? [22:47] RocketBoy_: the radiometrix radio modules, they have a 100K pullup on the data input? [22:47] sorry - HF reffers to the HF bands - the type of packet radio used there [22:47] HF = High frequency [22:48] below 30MHz [22:48] yep sure, but I mean what kind of numbers are they? [22:48] oh ok [22:48] cool [22:48] how does that stand from a regulatory POV? [22:49] its just narrow band - used cos the HF bands are more crowded than VHF [22:49] so its the same reglatorty wise [22:49] cool [22:49] as long as you stick using the licence exempt modules [22:50] and i guess that means larger antennas? [22:50] yeah on the HF bands the wavelength is much longer [22:51] however the free space path loss is dependant on frequency - so on HF the dB loss between 2 points in space is less than VHF [22:51] so purely practically, we'd need larger appendages on payloads [22:51] the lower the frequency the less the free space path loss [22:52] yeah -its a bit of a trade off - on HF you can get away with lower antenna gain [22:53] ok cool [22:53] but on VHF the FSPL is more - but can be compensated by antennas with more gain (e.g. yagis) [22:53] well I was looking at that sort of stuff on the kd7lmo site [22:53] I like they way they use DDS but use the GPS PPs to help combat drift [22:53] they claim to have had excellent results with it [22:57] yeah thats a way for sure - to use the Licence exempt modules in that way we would need to sniff the RF output phase lock it using the input control voltage [22:57] ... and phase lock it ... [22:57] lol [22:57] maybe for a rainier day [22:58] the lassen iq has 1pps output [22:58] yeah - I think thats the key here - how much effort do we want to expend on developing a perfect radio system [22:59] Laurenceb: yup [22:59] and it's sitting there looking useful [22:59] RocketBoy_: do you know how much it costs to get a DIY thing licensed? [23:00] gtg, cya folks [23:00] Laurenceb (n=Laurence@host81-157-248-24.range81-157.btcentralplus.com) left irc: [23:00] I ask this quite seriously as if it's of benefit to lots of people then I might be able to get some CUSF money [23:00] I have no real idea - i imagine it needs submitting to an independent test house at least - so low Ks GPB [23:02] I'm not sure what the advantage is - if its going to be LE then its going to have the same power and modes as the existing modules. [23:02] oh... [23:02] ks was more than I had in mind :\ [23:03] if its a licensed frequency its going to cost to license it. [23:03] I honestly don't think the 10mW 434MHz FM is a significant restriction - the NOVA flights showed it has the range [23:04] Putting an encoding scheme round the 434MHz LE modules is probably the better approach - extend the reliability that way [23:05] sure [23:06] I mean the worst case distance is 600km - line of sight at 100k ft [23:06] so what sort of encoding scheme do you reckon? [23:08] well I think thats the problem - we either go for an off the shelf decoder (like RTTY, packet or PSK31) [23:09] in which case we need to enulate the data they are expecting [23:09] or we build our own [23:10] in which case we need to do our own sound card software [23:11] the whole radio data thing is a complete trade off between complexity and performance [23:11] yeah, shame that :) [23:12] getting good performance with low signal levels requies complex encoding/decoding shemes [23:12] so what we need is a balance - reasonable performance from not too complex [23:14] standard packet radio would be a good choice - however it has a CRC check that most decoders discard the packet if one bit is corrupted [23:15] yeah, it's a same as for our low data rates just eyeballing it often seems sufficient [23:16] perhaps something like packet radio but with error correction - like Turbo codes or Reed-Solomon [23:17] Something like low shift FSK (or MFSK) with Turbo code or RS protected packets. [23:18] and multiple devices can operate on a single freq? [23:22] Yeah - thats true of packet in general [23:22] (well of most schemes anyway) [23:22] yeah, I guess that's quite exciting for the future [23:22] Its a bit like co-ax Ethernet [23:23] I guess - we should just decide what we want to do for Atlas [23:23] zeusbot_ (n=zeusbot2@host217-42-149-127.range217-42.btcentralplus.com) joined #highaltitude. [23:23] ok [23:23] well james has the source to cocoa modem [23:23] and thinks he can add ascii functionailty [23:24] the author said it would be trivial, anyway [23:24] sounds OK [23:26] Can anyone help with ubuntu? [23:26] equally, it's probably not too difficult to write something to decode a newer scheme as we have the source [23:26] I used it for about a fortnight.... I mean, ask, but I probably can't :) [23:27] yeah - OK well see what jcoxon has to say [23:28] well my problem is file systems - the DOS file systems keep comming and going from ubuntu [23:29] natrium42 might be able to help [23:29] it says it cant mount the file system when I try to navigate to them [23:29] actually it says - Unable to mount the volume [23:30] OK will I'll see if he can help [23:33] jcoxon (n=jcoxon@host217-42-149-127.range217-42.btcentralplus.com) joined #highaltitude. [23:33] hey all [23:33] just the chap - we were talking about you [23:34] are you happy enough with the coco code to convert it to ASCII [23:35] what speed and frequency shifts does it support? [23:35] indeed, just catching up with the logs [23:35] oh and i can help you with ubuntu [23:35] spiffing [23:35] right [23:35] so [23:36] i have the source - as ed has seen its an incredible program [23:36] i think i've identified where i need to make the changes but its going to take some work - and i need to read up on some theory [23:37] so lets not change the way we are doing things [23:37] sounds OK [23:37] keep rtty asci [23:37] i [23:37] as we can always decode it in windows [23:37] if i can't get it right [23:37] yes exactly [23:37] new scheme for another day [23:38] it'd be cool to try and get an uplink working with this new system too [23:38] yep that makes sense in the immediate future [23:38] well I have an uplink 3/4 built [23:39] for atlas we need simple tested kit [23:39] I don't think we can spare the extra weight for atlas [23:39] no agreed [23:39] if atlas works we can always expand [23:40] but sure in the mid term [23:40] perhaps a flight just to test rad-io systems would be a good idea [23:40] range test and uplink [23:41] true, perhaps a single balloon [23:41] fill it up lots [23:41] yeah [23:41] stormy day [23:41] and a good cutdown [23:42] yeah [23:42] okay [23:42] so lets continue as planned [23:42] yeah [23:43] OK so is edmoore doing the radio [23:43] is he? [23:43] (the transmitter end) [23:43] am I? [23:44] I'm asking [23:44] I thought we were using one of your rtty modules [23:44] oh [23:44] as they work [23:44] Can do - NP [23:44] but doesn't it have to be i2dc [23:44] no, we can bit-bash rs232 [23:44] he says..... [23:45] yeah better [23:45] fair enough [23:46] okay [23:46] james - do you still have a cutdown? [23:46] a circuit? [23:46] can we do soemthing that doesn't involve a massive cap? [23:46] yeah [23:47] just a mosfet and hope all will be well [23:47] hmmmm, we need these cutdowns to work [23:47] not necessarily [23:47] if we go for dual balloon [23:47] well, we'd like to wait for burst [23:48] on the big balloon [23:48] The main problem (without a cap) is that when the cutdown goes the current can drag the battery down [23:48] yeah - but then we are using the good lithiums [23:48] maybe soemthing to investigate [23:49] it's just I'm sure those caps must be >10g [23:49] hmmmm [23:49] When the igniter flares the plasma generates almost a short circuit [23:49] yes was thinking about that [23:49] - its not just the resistance of the igniter (which is 1.1 ohm) [23:49]