EMDRC HAB – Gearing Up For Our First Launch

The EMDRC (Eastern & Mountain District Radio Club – https://www.emdrc.com.au) High Altitude Balloon (HAB) group has been working towards it’s first launch here in Melbourne. The launch has been almost three years in the making, with COVID being unfortunately responsible for a lot of the delays. The EMDRC HAB group has obtained approval (also called instrument) from CASA (Civil Aviation Safety Authority), been in discussions with landowners to secure approval for use of their premises (Country Eastern Victoria) and has been working on putting together their payload for the first launch.

The EMDRC HAB group met on the 29th of July 2022 on discord to finalize the dates for the first launch. The session was attended by –

1. Chris Gommerall
2. Trystan J
3. Rohan A / VK3TRO
4. Mark / VK3IRV
5. Brad Q / VK3BKQ
6. Trevor W / VK3TWC

This post provides a summary of what was discussed –

1. Our primary launch day is the 28th of August 2022 with 4th of September being our backup. The launch schedule might need to move depending on weather, council approvals, etc.
2. Trevor / VK3TWC will reach out to our contacts within the Ararat council, request permission for the agreed dates.
3. We agreed that we’ll be meeting up at Docklands Makerspace on the 7th of August 2022 at 1230 to work on the payload, build the antenna, assemble the electronics.
4. Rohan / VK3TRO and Trevor / VK3TWC to link up over the phone, confirm that all the parts/equipment required to finalize build of the payload were in place before meeting up at Docklands on the 7th of August 2022.
5. We used the balloon gas calculator (http://randomsolutions.co.uk/Random_Aerospace/Balloons.html) and confirmed the amount of gas required for the balloon we are planning to use (Hwoyee 500). See image below that shows gas requirements for the balloon being used for the first test launch.
6. Chris G confirmed that pressure within the gas cylinder was down to 2000 PSI from 2200 PSI and given the amount of gas required for the launch we shouldn’t need to invest in another cylinder.
7. Mark VK5QI walked us through the design for a simple 1/4 wave ground plane antenna build that we might use for the payload. Design to be translated to build when we meet at Docklands Makerspace on the 7th of August 2022.
8. Rohan confirmed that all the payload integration work will be completed over the coming two weekends. Rohan has offered to take the payload (Wenet + Radiosonde) to a spot high above the ground e.g. Mount Dandenong and give the rest of the EMDRC HAB team an opportunity to test out reception from the Wenet payload + Radiosonde.
9. Update 02/08 : Trevor / VK3TWC spoke with Rohan / VK3TRO and confirmed that no additional items need to be procured for completion of the payload build on the 7th of Aug 2022 at Docklands Makerspace. Trevor / VK3TWC to take the second esky along to the build on the 7th.
10. Update 02/08 : Trevor / VK3TWC spoke with Chris G and agreed that he will procure 3 additional pairs of glasses, gloves from Bunnings. This is to accommodate the new members who might want to help with the launch.

If you are keen on joining the EMDRC HAB group please drop me a note at trevor at hack2 dot live or hab at emdrc dot com dot au. Happy to answer any questions you might have.