MHVSA (MHV Space Agency)

csirac2_ · January 15, 2016, 1:38pm

EDIT: Yes, please suggest a better name

We’re building a SatNOGS [1] [2] node at MHV. I’m carrying the cost, others welcome to contribute but mostly I’d massively appreciate help in 3D-printing the many parts this thing will take.

DONE:

UHF Helical Antenna

TODO:

We are adding our names against each part as we start prints (in the shared BOM spreadsheet on google docs) so that others know it’s being taken care of and avoids duplicating effort:

Rotator parts [here][8]
Rotator bom [here][9] (please add your name when you start a print, ask me if you can’t edit it)
Tripod parts [here][10]
Tripod bom [here][11] (please add your name when you start a print, ask me if you can’t edit it)
Automation electronics
RF/LNA/RTL-SDR testing
Software config

[1] http://satnogs.org/
[2] https://hackaday.io/project/1340-satnogs-global-network-of-ground-stations
[3] https://github.com/satnogs/satnogs-rotator
[4] http://satnogs.dozuki.com/Guide/SatNOGS+Rotator+v3+Mechanical+Assembly/7?lang=en
[5] https://github.com/satnogs/satnogs-rotator-controller
[6] https://github.com/satnogs/satnogs-tripod
[7] http://satnogs.dozuki.com/Guide/SatNOGS+Tripod+v2/4?lang=en
[8]: https://github.com/satnogs/satnogs-rotator/releases/download/v3.0.1/v3.0.1-40mm.zip
[9]: https://docs.google.com/spreadsheets/d/1Us8PCZAY7U2OZkkJcCpgPUc8FBVHKl9y_3qstFwGua4/edit?usp=sharing
[10]: https://github.com/satnogs/satnogs-tripod/tree/v2
[11]: https://docs.google.com/spreadsheets/d/1ioa15PZCJhG2bCKGDFIrgy5Nr6imrW6y5or2Wa6hgao/edit?usp=sharing

csirac2_ · January 15, 2016, 1:40pm

As @devdsp & @jambulance have expressed interest they are hereby tagged

mon · January 16, 2016, 2:52am

I wouldn’t mind trying to 3d print a part too - if that’s ok?

csirac2_ · January 16, 2016, 7:40am

I demand it! Dozens of hours of printing ahead of us. I’ll set up a Google docs with things printed/yet-to-be-printed so we don’t duplicate but for the time being just post what you print here

mon · January 16, 2016, 7:52am

YAY!

Harvs · January 16, 2016, 8:29am

If you need anything laser cut for it, let me know.

jambulance · January 18, 2016, 12:21am

Happy to use my printer at home to get some done too

Shanaek92 · January 19, 2016, 5:32am

This sounds amazing! Would love to be involved in any way I can. I haven’t done 3D printing before so this could be a learning experience for me.

csirac2_ · January 19, 2016, 1:19pm

Great to see you @Shanaek92, 3D printing is great fun and incredibly rewarding! I’d also love all the help I can get on the SatNOGS station

We didn’t have any of our usual 3D printer experts around tonight but some other new faces (many thanks to Paul & Alex!) got the Solidoodle up and running with our first successful print toward the project:

You can probably spot that piece in the admittedly more appealing coloured example below:

The full antenna assembly guide is at Helical Antenna v1 - SatNOGS

ManicDee · January 21, 2016, 4:06am

Random pseudo-related link: http://hackaday.com/2016/01/20/track-satellites-with-a-2-axis-antenna-positioner/

csirac2_ · January 21, 2016, 4:45am

Interesting! But no details/sourcecode… especially on those “$50” 60:1 worm-drive gearboxes! Would love to find them at that price locally.

Paul_Buckley · January 22, 2016, 11:22am

Hi everyone while at HMV tonight i printer the helix437-8r3-YO .

csirac2_ · January 22, 2016, 11:38am

Great stuff. I’d better do a bunnings trip soon and get the rest of the stuff

Paul_Buckley · January 26, 2016, 12:03pm

Printed these puppies(Helix437-8r3-T) tonight with a little help thanks Alex and a few new 3D printer tips for young players. Might just need to check their form with the condute to ensure that they are printed right before going on to print the last 6 or 7.

I have printed a couple of things now for this so by all means if any one else wants a go let me know and while I’m no expert I’m happy to help but it also ensures I don’t rush out and do it all.

csirac2_ · January 26, 2016, 11:21pm

There are two more git repositories with (supposedly) ~40-some hours of 3D printing combined, mostly in the az/el rotator box I think. No danger of running out of things to print yet, I think

Paul_Buckley · January 26, 2016, 11:59pm

well then by my maths there is 36 hours remaining.

jellyware · January 29, 2016, 10:50pm

mhv space agency! finally we may find a use for mhv.sppppppppppaaaaaaacccccee

jellyware · January 29, 2016, 10:51pm

mhv.space

Paul_Buckley · February 2, 2016, 12:15pm

Ok so tonight after some tense moments with the printer and with the pressure on from some new faces. Lol we managed to print another couple of parts after a bit of fiddling.

1 - Y connecter; and,
1 - T connector.

Leaving
1 Y connector and 6 T connectors to print for the main antenna. Hopefully I will be able to print a bit more tommorow night.

csirac2_ · March 15, 2016, 1:34pm

Thanks again @Paul_Buckley for doing just about all of the 3D printing so far (and @mon for doing the first trial pieces!)

@devdsp, @ian & @jambulance helping me do some tests last night - using a little FT-817 radio we made contact with another local amateur radio operator on 490.950MHz, the Isaacs Ridge repeater:

@Dexta_Bb did most of the hard work cutting & measuring three times each piece of wooden dowel (I couldn’t find any PVC in Bunnings that was 16mm, neither in plumbing or electrical supplies sections). There are some issues with the final dimensions we’ve ended up with but that was more due to the gluing process which was my fault:

Here’s the SWR just after building without any attempts at tuning:

Here’s the final SWR after my attempts to improve the tuning - I made it worse! I couldn’t get the antenna back to looking like that first measurement, oh well. Lucky it’s a receive antenna. I’ll try to control the spiral diameter much better next time SWR is meant to be lowest around 438MHz-ish: