I think helium from virtually any industrial gas supplier, even if labeled "balloon grade", is at least 99% purity, and often balloon grade is 99.99%. Five nines is decent for most all industrial

My payload went up at a slower rate that I had forecasted last time and I know I just got kind of lazy and sloppy. But even with me adding weight to the payload and not accounting for it the helium

Looking at the cross section dimensioned drawing and the photograph, it's pretty certain the tetroon was filled through an internally threaded port. After removing the fill tube from the port, the

I did that once. But the ping pong ball surface is too textured and does not make a bubble tight seal. I did a silicone ball and o ring. Even that getting the right

The latter (rapid ascent and gas release at the desired altitude) . Another idea in the paper is a lift balloon - where the superpressure balloon is filled to just the correct

Is this valve to be used for filling, or venting? It sounds like the intent was to allow for over fill for rapid ascent, and then release pressure at altitude. James VE6SRV -- James VE6SRV

Seems like a elegant design solution, but not having pico flight experience, I’m wondering about the mass penalty for pico flight. I'm estimating this value design to weigh between 7 and 10 grams.

Below is the image from the document Steve was referring to. Someone that flies the picos, does a simple valve sound like something that might work? It might make attaching the payload

We're in the final stages of having the videos ready on the "GPSL Live" channel at YouTube. Some are available now, and more will be coming soon. Thanks to Jim Emmert for editing the Zoom videos

Looks like that link does not work - search for the paper "Characteristics and Performance of Three Low-Cost Superpressure Balloon (Tetroon) Systems " Steve

See the ping-pong valve described here: https://tinyurl.com/y5ukveyb see fig 4 Steve Virus-free. www.avg.com

It seems like over inflation is a common problem. Could we come up with a simple (and light) pressure releif valve that is inseted in the fill tube? Maybe something that could be 3d printed. You

Hi All, I plotted the ascent and unexpected descent of the GPSL K5NOT-11 WSPR balloon I sent up. It was a WSPR Skytracker and SBS-13 balloon of which I had trouble sealing - the

Yep it is right....ocean currents are slow where it is currently located. - Bill WB8ELK

It doesn't appear to be moving much at all, can that be right? Greg K7RKT

It's here! Moving at a good clip too!

KM6BWB-10 will be over Iowa shortly.

Floyd, You can see all of the balloons currently flying in the World at: tracker.habhub.org or enter the GPSL callsigns of the balloons still flying on APRS.FI separated by commas. KM6BWB-10

What’s the trick or how can I find all the flyers on aprs or what ever tracking method. Dummies guide to balloon tracking.... Floyd KC5QBC

UPDATE: KM6BWB-10 returned to California today after a big loop into Mexico and out into the Pacific near Baja. Still flying high !!! - Bill WB8ELK