highaltitude.log.20200515

[00:08] Nick change: Oddstr13 -> Oddstr13[m]
[00:08] Nick change: Oddstr13[m] -> Oddstr13
[00:17] Oddstr13[m] (oddstr13ma@gateway/shell/matrix.org/x-zpkqdxukjapfzjvp) joined #highaltitude.
[00:39] <SpacenearUS> New position from 03BB10 after 032 days silence - 12https://tracker.habhub.org/#!qm=All&q=BB10
[00:49] <SpacenearUS> New vehicle on the map: 03KB6CAG-12_chase - 12https://tracker.habhub.org/#!qm=All&q=KB6CAG-12_chase
[01:50] Laurenceb (~laurence@223.141.208.46.dyn.plus.net) left irc: Ping timeout: 258 seconds
[02:29] DL7AD (~sven@2001:16b8:5c97:fe00:98b7:e193:d5fb:2d8b) left irc: Ping timeout: 260 seconds
[02:44] DL7AD (~sven@2001:16b8:5c1d:f600:f879:3220:2613:4510) joined #highaltitude.
[03:18] Axone (~Axone@lfbn-idf1-1-63-56.w82-124.abo.wanadoo.fr) left irc: Quit: ZNC 1.6.6+deb1ubuntu0.2 - http://znc.in
[03:21] Axone (~Axone@lfbn-idf1-1-63-56.w82-124.abo.wanadoo.fr) joined #highaltitude.
[03:28] <SpacenearUS> New position from 03W8MV-11 after 0311 hours silence - 12https://tracker.habhub.org/#!qm=All&q=W8MV-11
[03:38] ms7821 (~Mark@london.rack.ms) left irc: Remote host closed the connection
[03:55] tweetBot (~nodebot@philcrump.co.uk) left irc: Remote host closed the connection
[03:55] tweetBot (~nodebot@philcrump.co.uk) joined #highaltitude.
[04:47] YO3ICT (~YO3ICT@188.26.61.217) joined #highaltitude.
[05:04] Haxxa (~Harrison@2403-5800-4101-2e01-3065-64ff-fe66-6163.ip6.aussiebb.net) left irc: Ping timeout: 256 seconds
[05:07] Haxxa (~Harrison@202-142-138-13.cust.wide.net.au) joined #highaltitude.
[05:16] <SpacenearUS> New position from 03W5KUB-18 after 0314 hours silence - 12https://tracker.habhub.org/#!qm=All&q=W5KUB-18
[05:39] Haxxa (~Harrison@202-142-138-13.cust.wide.net.au) left irc: Quit: ZNC 1.6.2+deb1+jessie0 - http://znc.in
[06:30] <SpacenearUS> New vehicle on the map: 0319GSN0013_chase - 12https://tracker.habhub.org/#!qm=All&q=19GSN0013_chase
[06:45] Lahti (~Lahti@dytkmdxl10p0g7ycb7pjy-4.rev.dnainternet.fi) joined #highaltitude.
[06:57] daveake (uid144009@gateway/web/irccloud.com/x-rvvnhrzkziwgesys) joined #highaltitude.
[07:13] LazyLeopard (~irc-clien@chocky.lazyleopard.org.uk) joined #highaltitude.
[07:24] FireFighter (~firefight@2601:44:4200:ab4f:fc1f:b113:f07c:9a8e) joined #highaltitude.
[07:45] <SpacenearUS> New position from 03U4B-2 after 0312 hours silence - 12https://tracker.habhub.org/#!qm=All&q=U4B-2
[07:54] es5nhc (~es5nhc@static-213-100-139-88.cust.tele2.ee) joined #highaltitude.
[07:55] <SpacenearUS> New position from 03YO3ICT-PITS after 0316 hours silence - 12https://tracker.habhub.org/#!qm=All&q=YO3ICT-PITS
[08:10] es5nhc (~es5nhc@static-213-100-139-88.cust.tele2.ee) left irc: Ping timeout: 256 seconds
[08:36] es5nhc (~es5nhc@static-213-100-139-88.cust.tele2.ee) joined #highaltitude.
[09:02] JoHarKey (~UA1ZGK@77.73.139.102) joined #highaltitude.
[09:21] Haxxa (~Harrison@202-142-138-13.cust.wide.net.au) joined #highaltitude.
[09:24] michal_f (~michal_f_@17-153-196-109.itvmedia.pl) joined #highaltitude.
[09:41] michal_f (~michal_f_@17-153-196-109.itvmedia.pl) left irc: Read error: Connection reset by peer
[09:42] michal_f (~michal_f_@17-153-196-109.itvmedia.pl) joined #highaltitude.
[09:47] michal_f (~michal_f_@17-153-196-109.itvmedia.pl) left irc: Read error: Connection reset by peer
[09:54] <SpacenearUS> New position from 03PS-74 after 0320 hours silence - 12https://tracker.habhub.org/#!qm=All&q=PS-74
[09:55] xfce3 (~anony@cpe-85-10-26-226.dynamic.amis.net) left irc: Read error: Connection reset by peer
[10:01] chris_99 (uid26561@gateway/web/irccloud.com/x-lhwdzlxfarjbgutq) joined #highaltitude.
[10:12] <SpacenearUS> New position from 03PMO_B01L after 0312 hours silence - 12https://tracker.habhub.org/#!qm=All&q=PMO_B01L
[10:16] <SpacenearUS> New position from 03PMO_B01R after 038 days silence - 12https://tracker.habhub.org/#!qm=All&q=PMO_B01R
[10:28] <SpacenearUS> New vehicle on the map: 03SITS-2 - 12https://tracker.habhub.org/#!qm=All&q=SITS-2
[10:29] <SpacenearUS> New vehicle on the map: 03SITS-6 - 12https://tracker.habhub.org/#!qm=All&q=SITS-6
[10:46] <SpacenearUS> New vehicle on the map: 03ec7zv_chase - 12https://tracker.habhub.org/#!qm=All&q=ec7zv_chase
[10:55] ms7821 (~Mark@london.rack.ms) joined #highaltitude.
[10:59] <SpacenearUS> New vehicle on the map: 03c31vc_chase - 12https://tracker.habhub.org/#!qm=All&q=c31vc_chase
[11:33] Tryfonas (5e422643@ppp-94-66-38-67.home.otenet.gr) joined #highaltitude.
[11:37] Tryfonas (5e422643@ppp-94-66-38-67.home.otenet.gr) left #highaltitude.
[11:37] Tryfonas (5e422643@ppp-94-66-38-67.home.otenet.gr) joined #highaltitude.
[11:38] Tryfonas (5e422643@ppp-94-66-38-67.home.otenet.gr) left irc: Remote host closed the connection
[11:40] Tryfonas (5e422643@ppp-94-66-38-67.home.otenet.gr) joined #highaltitude.
[12:19] <chris_99> heh 2 people have asked me why they can't chat on this channel now. If there was space in the topic, it might be handy to tell people they need to register the nick possibly?
[12:20] <Tryfonas> Hello guys
[12:23] <Tryfonas> I represent a team from greece building a sounding rocket. We are currently exploring our options for the rockets telemetry and tracking! We really want to use APRS. Has anyone of you had any experience with it in the past?
[12:24] <chris_99> sounds cool, out of interest what are you using for the propellant
[12:26] <bertrik> how long is the rocket in the air?
[12:30] <Tryfonas> NOx (N2O) as oxidizer and ABS as fuel
[12:31] <Tryfonas> and we will fly to 3km above ground and descend with parachute
[12:31] <Tryfonas> approx. 1.5mins
[12:32] Thodoris (5548ae6b@athedsl-337613.home.otenet.gr) joined #highaltitude.
[12:33] <chris_99> cool, have you got a website on the rocket, be curious to see how it works roughly
[12:33] <Tryfonas> we are planning to opensource it
[12:34] <Tryfonas> but due to the corona crisis we are behind schedule
[12:34] <Tryfonas> we have a bit of the project on gitlab
[12:35] <chris_99> i've got a tiny model hybrid rocket that uses tiny n2o cartridges, which is why i'm curious how a proper rocket works with n2o
[12:35] <Tryfonas> https://gitlab.com/white-noise/cronos-rocket
[12:35] <Thodoris> Hello guys
[12:36] <Tryfonas> I mainly work on the avionic portion of the rocket
[12:36] <Tryfonas> my mate Thodoris is also on the project
[12:38] kevwal (569e9077@host86-158-144-119.range86-158.btcentralplus.com) joined #highaltitude.
[12:41] <Thodoris> I don't think that the CADs have been uploaded yet (And generally the rocket sub-components). We mainly work for avionics.
[12:43] Tryfonas (5e422643@ppp-94-66-38-67.home.otenet.gr) left irc: Ping timeout: 245 seconds
[12:49] Tryfonas (93668387@vpn-131-135.vpn.ntua.gr) joined #highaltitude.
[12:52] <PE2BZ> Tryfonas, at ¨rocket speed¨ isn´t aprs to slow for you ?
[12:53] <Tryfonas> I think it is
[12:53] <Tryfonas> I ve only seen aprs deployments with up to 2s refresh
[12:54] <Tryfonas> but we want to use it for its reliability in tracking the rocket's landing site
[12:54] <Tryfonas> due to 3km altitude and possible winds we might get blown off course by a lot and we are interested in using it for retrieval
[12:55] <Tryfonas> I wanted to ask if anyone has seen any realtime tracking implementations of the protocol
[12:55] <PE2BZ> What country are you from ?
[12:55] <Thodoris> Greece
[12:55] <PE2BZ> Does Greece have a big coverage of UHF RTTY receivers ? Or even LoRa ?
[12:56] <Thodoris> Yea
[12:56] <Tryfonas> we could use lora
[12:57] <PE2BZ> LoRa could have a fast update on the position. And all telemetry is stored ¨inside the rocket¨ also I assume ?
[12:57] <Tryfonas> also we are kind of new to the whole community (university students)
[12:58] <Tryfonas> if we were to implement real time tracking we could store it for safety
[12:58] <Thodoris> We have implemented a live update GUI. So, if the telemetry works properly
[12:58] <Thodoris> we would store the data at the ground station
[12:59] <PE2BZ> Is the telemetry only ¨position / speed¨ related? No other sensors ?
[12:59] <Tryfonas> GPS
[12:59] <Tryfonas> accelerometer
[12:59] <Tryfonas> and altitude
[12:59] <Thodoris> temperature also
[12:59] <Tryfonas> to monitor the tank
[13:02] <PE2BZ> That all fits in the LoRa telemetry string.
[13:03] <Tryfonas> Mostly we are interested in the landing site tracking
[13:03] <Tryfonas> for which aprs from what i ve seen is better
[13:04] <Tryfonas> And what we are internally discussing is using maybe a second telemetry for realtime for which we would most prob go with something like aprs
[13:06] <Tryfonas> And from what ive seen (correct me if im wrong) aprs can provide relatively reliable data for the distances we are studying
[13:07] <PE2BZ> I think APRS got good coverage. But in the end all depends on your last position, descend speed, impact speed, where the GPS receiver is and which way the TX antenne is pointing for a good recovery.
[13:08] <Thodoris> So what actually matters is the antenna's quality
[13:08] <Thodoris> ?
[13:09] <Darkside> so it sounds like for your application a high update rate is probably the biggest factor
[13:09] <Tryfonas> Also does anyone know if aprs modifies the signal (sorry for newbie question we are trying to learn)
[13:09] <PE2BZ> Which for 2 meter APRS (1/4 wave groundplane) better not should be pointing to the ground when the rocket descends
[13:09] <Darkside> so you can get positions as close asp ossible in time to landing
[13:10] <Darkside> if you are using the APRS *network* then you need to limit your update rate to avoid congesting the network
[13:10] <Darkside> if you use APRS on a different frequency, and receive locally (as you should be doing anyway), then you can do whatever you want
[13:10] <Tryfonas> wdym 2m APRS i thought the freq was 70cm
[13:10] <Darkside> APRS is usually used on 2m
[13:11] <Darkside> well, thats where most of the APRS network receivers/reearter are
[13:11] <Darkside> repeaters*
[13:11] <Darkside> nothign stopping you using the modulation on another frequency
[13:11] <PE2BZ> Tryfonas, are you licensed amateur radio user ?
[13:11] <Darkside> again, you will have a local receiver
[13:11] <Tryfonas> We are working to get HAM
[13:11] <Darkside> and yes, you need an amateur radio license to be able to use this stuff
[13:11] <Tryfonas> but currently got pushed back bc of corona and exams
[13:12] <Darkside> if you have very limited experiene with radio, and can handle the weight budget, then an off-the-shelf aprs tracker dialed up to a high update rate may be your best option
[13:12] <Darkside> running on a non-standard frequency
[13:12] <Darkside> something like the picoAPRS transmitter
[13:12] <Tryfonas> Darkside we are mostly interested in the recovery of the rocket. As you have possible understood in terms of telemetry we have very little experience..
[13:13] <Thodoris> Also, we would like to be able to send a signal to the rocket (while on air)
[13:13] <Darkside> what kind of cross-ranges are we talking about
[13:13] <Darkside> ok now you're going to a whole nother level of complexity
[13:13] <Darkside> if you want an off-the-shelf solution, you may want to look at the altus metrum products
[13:14] <Tryfonas> the bidirectional refers to the scenario where we do go with real time
[13:14] <Darkside> they do a bunch of boards with do this, designed specifically for model rocketry
[13:14] <Darkside> bidirectional links, commanding pyros, etc
[13:14] <Tryfonas> But we were thinking that going completely with an off the self solution we wont get our hands dirty and learn
[13:15] <Darkside> https://altusmetrum.org/TeleMetrum/
[13:15] <Tryfonas> wdym cross ranges?
[13:15] <Darkside> launch site to landing site
[13:15] <Thodoris> around 5km
[13:15] <Tryfonas> 5km approx
[13:15] <Darkside> sure, you will learn more doing it yourself, but its a seriously big project to do a complete bidirectional rf link from scratch
[13:15] <Darkside> if the objective is to learn how to build a link, then sure
[13:16] <Darkside> if the objective is to test a rocket, then use an off-the-shelf product
[13:16] <PE2BZ> Tryfonas, out of curiosity, what´s the deadline, if any ?
[13:17] <Darkside> because if your project is reliant on your telemetry link working reliably, and you only have a few months to build it, then doing it yourself is high risk
[13:17] <Darkside> especially if you're coming into the project cold
[13:17] <Thodoris> Next year i guess
[13:17] <Tryfonas> around september
[13:17] <Darkside> you need to decide what the real aims of the project are
[13:17] <PE2BZ> september next year ? Or are these two answers not releated ?
[13:17] <Thodoris> not related
[13:18] <Darkside> but it might be worth getting something like the telemetrum kit as a backup
[13:18] <Tryfonas> darkside thanks to sponsors we are able to combine both
[13:18] <Darkside> since its a well tested solution, used by many rocket groups around the world
[13:18] <Darkside> if you want to go try and design your own, then fine - but having a fallback is probably a good idea
[13:19] <Tryfonas> we have an avionics team where we are only interested in the telemetry so we could by the off the self solution and try to develop knowledge for future project
[13:19] <PE2BZ> Tryfonas, you can allways test. Even with a HE filled balloon that should not be to expensive.
[13:19] <Tryfonas> thats what we wanted to use for testing
[13:19] <Tryfonas> of range etc
[13:20] <Darkside> so it will be unlikely that you will be able to receive the signal once its landed on the ground
[13:20] <Darkside> the aim would be to maintain tracking to as close as possible to landing
[13:20] <Darkside> even if its 100m up, thats going to give you a pretty small search radius
[13:20] <Darkside> even if its a few hundred metres up, it will help
[13:20] <Tryfonas> yes
[13:21] <Darkside> and line of sight over 5km is pretty easy for most of these radio links
[13:21] <Tryfonas> even a km would be acceptable
[13:21] <PE2BZ> Darkside, should the predictor be able to handle rocket speeds for prediction ?
[13:21] <Darkside> hrm
[13:21] <Darkside> im not sure the predictor is so useful for sockets
[13:21] <Darkside> rockets*
[13:22] <Tryfonas> what is predictor
[13:22] <Darkside> we have a high altitude balloon flight path predictor
[13:22] <PE2BZ> What is the rocket speed in m/s when ascending ?
[13:22] <PE2BZ> approx ?
[13:22] <Darkside> PE2BZ: forget the ascent
[13:22] <Darkside> approximation is that it goes straight up
[13:22] <Tryfonas> below 1 mach
[13:22] <PE2BZ> Darkside, right :-)
[13:22] <Tryfonas> something like 300m/s
[13:22] <Darkside> however, being able to predict the *descent* may be useful
[13:23] <Tryfonas> top speed
[13:23] <Tryfonas> yes
[13:23] <Darkside> Tryfonas: what speed to the rockets usually impact at under parachute?
[13:23] <Tryfonas> either way i think for this speed even gps isnt even reliable for tracking
[13:23] <Darkside> and what altitude are you targetting
[13:23] <Tryfonas> 3km
[13:23] <Darkside> ok lemme try something
[13:24] <Darkside> http://predict.habhub.org/#!/uuid=b7e5863b993f2d4013b80d68bacab25f5c3cc11c
[13:24] <Tryfonas> Darkside let me contact my propulsion engineer
[13:24] <Darkside> so thats a 'descent' prediction
[13:24] <Darkside> i set the launch altitude and the burst altitude to the same value of 3km, and estimated a landing rate of 5m/s
[13:24] <Darkside> the prediction (zoom in) shows the path from 'burst' (rocket peak altitude) to landing (green dot)
[13:25] <Darkside> this assumes it is under parachute
[13:25] <Tryfonas> ok how do i see the cross distance?
[13:25] <Tryfonas> cross range*
[13:26] <Darkside> look in the top right corner
[13:26] <Darkside> there's a little scenario information box
[13:26] <Darkside> Range: 3.4km, Flight Time: 0hr09
[13:26] <Tryfonas> ok
[13:26] <Darkside> note that this is not how the predictor was meant to be used, so i don't know how useful it will be
[13:26] <Tryfonas> this assumes allso air ?
[13:26] <Darkside> yes
[13:27] <Darkside> it will use an air density model, and its assuming the payload is falling under a parachute which results in a landing descent rate of whatever you set (in this case 5m/s)
[13:27] <Tryfonas> because in our simulations we get sligthy different numbers adjusting for our Cd and weight
[13:27] <Darkside> of course
[13:27] <Darkside> the predictor simplifies things a bit
[13:28] <Darkside> but it may be enough to give you an idea of what direction its going to go
[13:28] <Darkside> and a rough range
[13:28] <Tryfonas> Our rocket isnt very aerodynamically neutral especially in the z direction
[13:28] <Darkside> on the point of the GPS - yes, some GPS modules will drop GPS lock at high accelerations
[13:28] <Tryfonas> yeah of course i get
[13:28] <Tryfonas> nice tool btw
[13:28] <Darkside> the uBlox GPS series have a dynamic model mode which works well in high accelerations, up to 4G i believe
[13:28] <Darkside> the telemetrym board uses one of them
[13:29] <Darkside> so that gives you position tracking up to burnout, then of course the acceleration drops and the gps works fine anyway
[13:30] <Darkside> you mentioned other telemetry earlier - its worth noting that the altus metrum boards have onboard sensors, but given the entire project is open source, it would most likely be possible to add other sensors if you wanted that
[13:30] <Thodoris> As far as gps is concerned, we think that this is good enough https://www.sparkfun.com/products/15193
[13:30] <Darkside> thats the same chipset as what im talkin gabout
[13:31] <Darkside> ublox 8-series
[13:31] <Darkside> same chipset used on the altus metrum boards
[13:31] <Tryfonas> yes
[13:31] <Tryfonas> this should work fine
[13:31] <Darkside> you need to configure it correctly
[13:32] <Tryfonas> when you mention burnout wdym?
[13:32] <Darkside> well, if you are using the gps module directly
[13:32] <Darkside> rockets goes up, engines stop at some point, right?
[13:32] <Tryfonas> we will hook it to an Arduino
[13:32] <Darkside> acceleration stops
[13:32] <Tryfonas> yes
[13:32] <Tryfonas> oh
[13:32] <Tryfonas> misread the msf
[13:32] <Tryfonas> msg*
[13:33] <Thodoris> at the peak yea, but only in the z-direction
[13:33] <Darkside> if you're building your own electronics, you're going to be have to very careful with design to handle high accelerations
[13:33] <Darkside> i know agg has done a lot with model rocket electronics design
[13:33] <Darkside> and UKHAS in general
[13:33] <Tryfonas> Darkside you seem pretty knowledgable if i am not intruding what projects are you working on?
[13:33] <YO3ICT> you need to configure the GPS on the ground before liftoff to put it in high accel mode
[13:34] <Darkside> Tryfonas: i'm an RF/Systems engineer as a day-job
[13:34] <Darkside> i work on lots of stuff
[13:34] <Tryfonas> Great!!
[13:34] <YO3ICT> Dynamic models on the ublox : https://imgur.com/a/EVO0XVQ
[13:34] <Darkside> mostly big radar systems
[13:34] itsonlyluis_ (~luis@cpc156977-wake10-2-0-cust450.17-1.cable.virginm.net) left irc: Ping timeout: 264 seconds
[13:34] <Darkside> but most recently i've been doing drone-based antenna pattern measurement
[13:35] itsonlyluis_ (~luis@cpc156977-wake10-2-0-cust450.17-1.cable.virginm.net) joined #highaltitude.
[13:35] <Darkside> part of that was building a bi-directional telemetry system to get telemetry to/from a payload attached to a drone
[13:35] <Darkside> i ended up using LoRa modules, running at a reasonably high data rate
[13:36] <Tryfonas> so radiation patterns?
[13:36] <Darkside> if you're going to build your own system, that may be an easy path
[13:36] <Darkside> yes
[13:36] <agg> Even in 4G mode you can expect the ublox to lose lock at takeoff and hopefully regain it sometime after burnout
[13:36] <Tryfonas> Seems pretty interesting!
[13:36] <Darkside> agg: ahh interesting
[13:36] <Darkside> ok so agg is here
[13:36] <Darkside> agg is awesome, agg is experienced, agg has done all this before
[13:36] <Tryfonas> Can we rely on it getting back?
[13:36] Action: agg blushes
[13:37] <agg> Tryfonas: I mean there are no guarantees, the rocket might just explode :p
[13:37] <agg> So long as you put the ublox into 4G airborne mode I would give it good odds of recovering lock before apogee and then you get data all the way down until your radio link cuts out
[13:38] <Tryfonas> ahahaha its surely a possibility
[13:38] <Darkside> nowdays as much as it offends my open-source sensibilities, the lora modules are probably the path-of-least-resistance to getting a radio link going. you just need to carefully decide what kind of data you want down the link and what kind of update rate you need
[13:39] <Darkside> and then set the LoRa modulation settings so that you maximise your sensitivity
[13:39] <Tryfonas> We tried looking into lora but they are pushing LoraWan so agressively that most resources are lost
[13:39] <Darkside> nonsense
[13:39] <Darkside> rfm98w module
[13:39] <Darkside> theres libraries for that
[13:40] <Tryfonas> ok will check
[13:41] <Darkside> you can probably just rip a bunch of dave ackermans code
[13:41] <Darkside> that's what i did lol
[13:41] <Thodoris> Who is he?
[13:41] <Tryfonas> we are kinda pushed to look into mostly opensource solutions by our sponsors'=(
[13:41] <Tryfonas> =(
[13:41] <PE2BZ> He´s almost as great as agg ;-)
[13:41] <Darkside> https://github.com/projecthorus/FlexTrack-Horus/blob/master/lora.ino
[13:42] <Darkside> well thats the code from my cutdown payload, but its basically daveake's code
[13:42] <Darkside> theres a lot of crap in that code that you probably wouldn tneed though
[13:43] <Darkside> looks like RadioLib might be an option: https://github.com/jgromes/RadioLib
[13:44] <Darkside> https://github.com/jgromes/RadioLib/blob/master/examples/SX127x/SX127x_Transmit/SX127x_Transmit.ino
[13:44] <Thodoris> As an alternative solution, is there an aprs module associated with arduino?
[13:44] <Darkside> voila
[13:44] <Darkside> if we're talking lora, we're not talking aprs
[13:44] <Darkside> different modulation
[13:44] <Tryfonas> yes for aprs not lora
[13:45] <Darkside> there probably is, but its quite possible a lora system might be better suited
[13:45] <Darkside> with APRS you will need to use a higher transmit power for the same datarate
[13:45] <Darkside> and its probably going to be a one-way system
[13:45] <Tryfonas> because we saw a lot of the ukhas projects using it
[13:45] <Tryfonas> aprs*
[13:46] <Darkside> nope
[13:46] <Darkside> well
[13:46] <Darkside> not the UK-specific ones anyway
[13:46] <Darkside> using APRS airborne is illegal in the UK
[13:46] <Tryfonas> oh didnt know that
[13:46] <Darkside> what you have probably seen is people using APRS on long-duration floater flights
[13:46] <Tryfonas> we saw the euros project i think using it to travel coast to coast
[13:46] <Darkside> the only reason APRS is used by these flights is because there is an existing network of automated receivers around the world
[13:47] <Darkside> this is not going to be useful for your use-case
[13:47] <YO3ICT> Darkside: Even airborne WSPR is illegal in the UK
[13:47] Hoogvlieger (~Hoogvlieg@2001:1c03:3e10:3c00:8c4b:7490:7933:897b) joined #highaltitude.
[13:47] <Darkside> YO3ICT: sure, airborne amateur radio in general is illegal in the UK
[13:47] <Darkside> Tryfonas: given that you want fast updates rates, you are not really going to be able to use your local APRS network, so you're going to be reliant on your own receiver
[13:48] <YO3ICT> Darkside: What difference does that make, WSPR at 10k coveres 5000km anyway. Practically it does not matter if in UK's airspace or over the North Sea.
[13:48] <Darkside> and if you're reliant on your own receiver, then you can build a radio system that performs better than an APRS system for a given transmit poer
[13:48] <Darkside> YO3ICT: yes we get it the rules are stupid
[13:48] <Darkside> move on
[13:49] <Darkside> send me a picotracker already :P
[13:49] <Darkside> APRS not illegal airborne here in australia
[13:49] <YO3ICT> Picotracker? My ICT Tracker?
[13:50] <Thodoris> I am checking it out
[13:51] <Darkside> Tryfonas: if you are after a two-way system, then building something using lora modules might be a good option
[13:51] <Darkside> with the right settings (and depending on the data rate you are after), you coudl easily get updates of a few Hz at a few km range
[13:53] <Darkside> it really comes down to what data do you need to send, how often do you need to send it
[13:53] <Tryfonas> do you know the baud rate limit maybe on lora?
[13:54] <Darkside> i think you can push maybe 8kbit/s through at the higher rates. it might be more
[13:54] <Darkside> what telemetry do you need to relay to the ground?
[13:55] <Tryfonas> we were thinking maybe 12k baud
[13:55] <Darkside> that isnt what i asked
[13:55] <Tryfonas> oh srr
[13:55] <Darkside> what do you need to send to the ground
[13:55] <Tryfonas> gps
[13:55] Laurenceb (~laurence@223.141.208.46.dyn.plus.net) joined #highaltitude.
[13:55] <Darkside> anything else apart from GPS?
[13:56] <daveake> accel? flight mode? chute deply flag ?
[13:56] <daveake> deploy
[13:56] <Darkside> because realistically you might only need to be sending maybe a few tens of *bytes* per second
[13:56] <Tryfonas> in what we are currently discussing meaning recovery only we only need gps
[13:56] <Darkside> sure
[13:56] <Darkside> so if you were happy with one gps update per second, you need to send 10 bytes of data per second
[13:57] <daveake> You just need the GPS to track and recover ?
[13:57] <Darkside> 4 bytes each for lat/lon as a floating point number, and 2 bytes for altitude
[13:57] <Darkside> thats 10 bytes.
[13:57] <Tryfonas> but if we were to try to to some real tracking we have some other sensors (we will sore in rocket) and maybe try to transmit
[13:57] <Darkside> if you dialed a lora modem to the point wher it was only transmitting 10 bytes per second, you will have *hundreds* of km of line of sight range
[13:57] <daveake> I think I'd want to log GPS and sensors as quickly as I could, and separately send out GPS every 1-5 seconds for tracking
[13:58] <Tryfonas> something like that
[13:58] <daveake> That ublox will do iirc 18Hz updates
[13:58] <Darkside> i would say that something like dave's flextrack system might be a good starting point
[13:58] <Darkside> its designed for arduino stuff
[13:58] <Darkside> talks to a lora module
[13:58] <Darkside> he has a rpi groundstation that would probably work ok for this
[13:59] <Darkside> probably wouldnt want to feed data to the habhub tracker map, but you will see the lat/long locally
[13:59] <Darkside> and can feed the data into something else
[14:01] <Tryfonas> Darkside ok I will check it
[14:04] <Tryfonas> Not very well read on Lora but i uses Frequency Hopping right?
[14:04] <Darkside> it can
[14:04] <Tryfonas> so it can toggled?
[14:04] <Darkside> in some cases you are legally required to
[14:04] <Darkside> theres a lot of things you can set on the lora modules
[14:04] <Tryfonas> wdym?
[14:04] <Tryfonas> required?
[14:05] <Darkside> in many ISM band applications transmitters are legally required to use frequency hopping
[14:05] <Darkside> however if you are using it under an amateur radio license, and can find a bit of clear spectrum in, say, the 70cm amateur radio band, then you wouldnt need to do that
[14:06] <Tryfonas> oh thats nice
[14:06] <Thodoris> The frequency hopping is the same as spread spectrum?
[14:06] <Darkside> no
[14:07] <Thodoris> What's the difference?
[14:07] <Darkside> hrm
[14:07] <YO3ICT> daveake: Is there any simple gateway-to-PITS uplink example available? Something just to send a flag or two up to the payload
[14:07] <Darkside> frequency hopping is more about not using any one bit of spectrum for too long, so other users can use it
[14:08] <Darkside> i guess spread spectrum is kind of related? but its more about dealing with in-band interference i think
[14:08] <Darkside> not entirely sure tbh
[14:08] <Darkside> lora's 'spread spectrum' is definiely about trying to deal with the presence of in-band interferers
[14:08] <Tryfonas> we are asking bc we would like to use a fixed frequency
[14:08] <Darkside> yes
[14:09] <craag> note that lora is not spread-spectrum in the way that any frequency allocation rules define spread spectrum.
[14:09] <Darkside> if you are operating in an amateur radio band then you should be fine
[14:09] <daveake> YO3ICT: Not really; it's on my list :)
[14:10] <Tryfonas> oh nice
[14:10] <Darkside> YO3ICT: i have code that does this, but not to a PITS
[14:10] <Darkside> i developed my cutdown system in parallel with daveake developing PITS, and the packet formats forked off pretty heavily
[14:13] <YO3ICT> My cutdown system is automatic https://imgur.com/a/97044Jl but I would really love to be able to send the command myself
[14:14] <Darkside> yeah
[14:14] <Darkside> i do that via lora
[14:14] <Darkside> lemme fidn links
[14:14] <Darkside> https://github.com/projecthorus/horus_utils/wiki#horusgroundstation-processing-of-data-from-loraudpserver
[14:15] <Darkside> https://github.com/projecthorus/FlexTrack-Horus
[14:15] <SpacenearUS> New position from 03PH1M-RTTY after 035 days silence - 12https://tracker.habhub.org/#!qm=All&q=PH1M-RTTY
[14:16] <SpacenearUS> New position from 03PH1M-4FSK after 035 days silence - 12https://tracker.habhub.org/#!qm=All&q=PH1M-4FSK
[14:16] <YO3ICT> Darkside: that is beyond my coding skills
[14:17] <Darkside> welp
[14:17] <Darkside> cant help much then
[14:26] <Tryfonas> anyway guys may I ask all of you here are from the habhub project?
[14:26] <Darkside> agg: wrote a bunch o fit
[14:26] <Darkside> of it
[14:26] <Darkside> i hack on it and break it by sending in lots of radiosonde traffix
[14:26] <Darkside> traffic*
[14:26] <Tryfonas> hahaha
[14:27] <Darkside> a lot of people here do their own launches, and use habhub for tracking their flights
[14:27] <Darkside> myself included
[14:27] <Tryfonas> cool
[14:27] <Tryfonas> you are all uk based?
[14:27] <Darkside> i'm in australia
[14:28] <Tryfonas> how does one get involved in it?
[14:28] <Tryfonas> seems pretty cool
[14:28] <Darkside> this is a good starting guide: http://www.daveakerman.com/?p=1732
[14:30] <YO3ICT> daveake: Thanks for the answer. Let me buy you a couple of beers, maybe the simple uplink example will get a bit higher on your list :)
[14:31] <daveake> heh :). Well I have to finish the Pi s/w for the PITS replacement, then I'll do it
[14:34] <Tryfonas> thanks
[14:36] Tryfonas (93668387@vpn-131-135.vpn.ntua.gr) left irc: Remote host closed the connection
[14:37] <PE2BZ> I am not based.... I am just hanging around on a big HE balloon....
[14:38] <YO3ICT> daveake: The little Taoglas patch seems to perform well for Galileo and I did enable that on my payload so you might consider adding that. It's a pity the M8s do not have flash, so we can take advantage of the 30 seconds or so of boot time. When changing the GNSS configuration, the M8 resets itself. When do you expect to release the PITS replacement?
[14:39] Thodoris (5548ae6b@athedsl-337613.home.otenet.gr) left irc: Remote host closed the connection
[14:39] <daveake> https://twitter.com/uputronics/status/1256316512404725762
[15:11] <SM0ULC-David> daveake: really cool work with the adsb stuff :)
[15:12] <daveake> ta, yes that's been keeping me occupied this week :)
[15:12] <daveake> https://usercontent.irccloud-cdn.com/file/K1BfZ2Th/image.png
[15:13] <daveake> Difficult to stress-test at the mo :D
[15:15] <PE2BZ> Hi, would anyone know if xU4B-6 and xU4B-7 are in test or really flying ?
[15:18] <PE2BZ> Both are in the parser logtail, appear flying, but not on the map.
[15:20] Tryfonas (93668387@vpn-131-135.vpn.ntua.gr) joined #highaltitude.
[15:21] Tryfonas (93668387@vpn-131-135.vpn.ntua.gr) left irc: Remote host closed the connection
[15:32] <Darkside> PE2BZ: might be a rule on the number of sats
[15:33] <Darkside> oh nvm
[15:33] <Darkside> differnet payload
[15:34] <PE2BZ> Get some sleep ;-)
[15:40] OLHZN (~Tory@cpe-66-66-13-40.rochester.res.rr.com) joined #highaltitude.
[15:51] OLHZN (~Tory@cpe-66-66-13-40.rochester.res.rr.com) left irc: Read error: Connection reset by peer
[15:57] OLHZN (~Tory@cpe-66-66-13-40.rochester.res.rr.com) joined #highaltitude.
[16:14] es5nhc (~es5nhc@static-213-100-139-88.cust.tele2.ee) left irc: Ping timeout: 256 seconds
[16:20] snakedGT (~snaked@pdpc/supporter/active/snaked) joined #highaltitude.
[16:20] Nick change: snakedGT -> mirror_snaked
[16:24] mirror_snaked (~snaked@pdpc/supporter/active/snaked) left irc: Client Quit
[16:35] gb73d (gb73d@79-76-131-66.dynamic.dsl.as9105.com) joined #highaltitude.
[16:42] JoHarKey (~UA1ZGK@77.73.139.102) left irc: Quit: Going offline, see ya! (www.adiirc.com)
[16:47] <SA6BSS-Mike> PE2BZ: I disabled those flight by putting a x befor the calls so they dont upload or show to habhub
[16:48] <SA6BSS-Mike> they are stil in the script but Dave is reusing calls which confuse the script on top of two payloads that pup up from time to time even more confuse the script
[16:52] <SpacenearUS> New position from 03YO3ICT-PITS after 039 hours silence - 12https://tracker.habhub.org/#!qm=All&q=YO3ICT-PITS
[16:55] es5nhc (~es5nhc@static-213-100-139-88.cust.tele2.ee) joined #highaltitude.
[16:57] M6BQV (~m6bqv@189.232.208.46.dyn.plus.net) joined #highaltitude.
[17:07] <YO3ICT> daveake: I am sending "SMS" from the gateway to the payload. How should be .sms file formatted to avoid CRC error message on the payload?
[17:09] <SpacenearUS> New vehicle on the map: 03Ea6afz_chase - 12https://tracker.habhub.org/#!qm=All&q=Ea6afz_chase
[17:11] <SpacenearUS> New vehicle on the map: 03BZ3 - 12https://tracker.habhub.org/#!qm=All&q=BZ3
[17:24] OLHZN (~Tory@cpe-66-66-13-40.rochester.res.rr.com) left irc: Read error: Connection reset by peer
[17:26] gb73d (gb73d@79-76-131-66.dynamic.dsl.as9105.com) left irc: Excess Flood
[17:27] gb73d (gb73d@79-76-131-66.dynamic.dsl.as9105.com) joined #highaltitude.
[17:27] M6BQV (~m6bqv@189.232.208.46.dyn.plus.net) left irc: Quit: Chao for now!
[17:49] <SpacenearUS> New position from 03PS-76 after 0313 hours silence - 12https://tracker.habhub.org/#!qm=All&q=PS-76
[18:09] es5nhc (~es5nhc@static-213-100-139-88.cust.tele2.ee) left irc: Ping timeout: 256 seconds
[18:21] <SpacenearUS> New vehicle on the map: 03DC2EH-6 - 12https://tracker.habhub.org/#!qm=All&q=DC2EH-6
[18:29] YO3ICT (YO3ICT@188.26.61.217) left #highaltitude.
[19:02] Kodar (~Kodar@93-142-39-151.adsl.net.t-com.hr) joined #highaltitude.
[19:05] GyroW (~GyroW@unaffiliated/gyrow) left irc: Remote host closed the connection
[19:05] GyroW_ (~GyroW@d54C03E98.access.telenet.be) joined #highaltitude.
[19:21] kevwal (569e9077@host86-158-144-119.range86-158.btcentralplus.com) left irc: Remote host closed the connection
[19:57] <SpacenearUS> New vehicle on the map: 03KK6UUQ-5 - 12https://tracker.habhub.org/#!qm=All&q=KK6UUQ-5
[19:59] gb73d (gb73d@79-76-131-66.dynamic.dsl.as9105.com) left irc:
[20:03] <SpacenearUS> New vehicle on the map: 03KK6UMQ-5 - 12https://tracker.habhub.org/#!qm=All&q=KK6UMQ-5
[20:21] geheimnis` (~geheimnis@23.226.237.192) left irc: Ping timeout: 264 seconds
[20:24] geheimnis` (~geheimnis@23.226.237.192) joined #highaltitude.
[20:44] <SpacenearUS> New vehicle on the map: 03TGM_chase - 12https://tracker.habhub.org/#!qm=All&q=TGM_chase
[20:45] <SpacenearUS> New vehicle on the map: 03BIOWL1_chase - 12https://tracker.habhub.org/#!qm=All&q=BIOWL1_chase
[20:54] Hoogvlieger (~Hoogvlieg@2001:1c03:3e10:3c00:8c4b:7490:7933:897b) left irc: Ping timeout: 260 seconds
[21:07] <SpacenearUS> New vehicle on the map: 03DG0CCO_chase - 12https://tracker.habhub.org/#!qm=All&q=DG0CCO_chase
[21:16] chris_99 (uid26561@gateway/web/irccloud.com/x-lhwdzlxfarjbgutq) left irc:
[21:28] FireFighter (~firefight@2601:44:4200:ab4f:fc1f:b113:f07c:9a8e) left irc: Remote host closed the connection
[21:44] <SpacenearUS> New vehicle on the map: 03AM1SDL_chase - 12https://tracker.habhub.org/#!qm=All&q=AM1SDL_chase
[22:15] Lahti (~Lahti@dytkmdxl10p0g7ycb7pjy-4.rev.dnainternet.fi) left irc: Quit: Lähdössä
[22:52] LazyLeopard (~irc-clien@chocky.lazyleopard.org.uk) left irc: Quit: Textual IRC Client: www.textualapp.com
[22:59] Kodar (~Kodar@93-142-39-151.adsl.net.t-com.hr) left irc: Read error: Connection reset by peer
[23:05] Hoogvlieger (~Hoogvlieg@2001:1c03:3e10:3c00:34ef:999f:cce8:9ec) joined #highaltitude.
[23:05] daveake (uid144009@gateway/web/irccloud.com/x-rvvnhrzkziwgesys) left irc: Quit: Connection closed for inactivity
[00:00] --- Sat May 16 2020