Getting Started / Technical Page (this section will continue to be updated 10.4.22)

Our Pico Balloon, AA6DY launched on September 3rd 2022, has already gone around the world once. While tracking this balloon, we found that we don’t always receive the needed information to accurately track location, altitude and speed. Below is an explanation from Michael Seedman, AA6DY on what we need to track our balloons.

Our tracker sends out one message on the 2’s (02, 12, 22, 32, 42, 52 after the hour), and one on the 4’s. Any ham station that hears our signal will post the message to a database over the internet. To be able to piece together all the information to accurately locate the balloon, we need both messages. If we just receive the message sent on the 2’s (first packet), we can estimate our balloon’s location somewhere within a 7,000 square mile grid, and an altitude within 1,200 meters. If we also receive the message sent on the 4’s, we can locate our balloon to a 15 square mile grid and an altitude within 320 feet. The first message has a ham call included in the packet, but to save space in the packet, the second only has a hint of its sender.

Finding the Right Balloons, the right Gas

All of our balloons are adertised as a party balloon, so if you’re planning a big party or a wedding, we have a dual purpose balloon. We first wanted to make our own balloons but with an upcoming launch in Spetember of 2021, we settled on the Qualatex 36″ party balloon which we used up until our December 2021 launch. We found that our early launches never flew more than a day. Were we leaking gas, having a sealing issue? What we discovered after filling it to burst in a test, was that these balloons although work very well at ground level for lively parties, didn’t work for our Pico Project. We found that these balloons would reach altitude, then steadily lose altitude.

We were in a big learning curve from the start, what we didn’t know at the time was that there’s a science to calculating the gas fill based on size of the balloon.

Before we get too far into what works and what hasn’t, I’d like to recognize the Pico Balloon io group where we receive support on anything you want to know about our hobbly, I would recommend joining https://groups.io/g/picoballoon

The key to all of these balloons is they perform better if they’re pe strectched, and there’s a science to that as well, another reason to join the io group.

It was through the io group that we found the 36″ Chinese made balloon. That’s the best way we can describe this, it’s made in China, and it’s a couple of bucks, available in groups of 10 at a discount. 36″ clear party balloon, Aliexpress Party World Store 10 lot

The 36″ Chinese made balloon is round and flatter, we call it a pillow or pancake style. We flew this balloon for many long flights, it only needs to be heat sealed to secure. The issue is that we were limited in altitude to 32,000 feet. The balloon has stamina, we flew it on December 22nd for 19 days, spending 8 days touring the Marshall Islands.

To get to that magic altitude of 47,000 feet we needed a round also known as sphere balloon. We became aware of two different manufactured sphere’s 32″ and bought them both. The downside is there’s more preparation work, needs to be filled the night before launch and sealed with a special glue and tape.

We found that our balloons will lose 1/2 gram of gas overnight and each day before launch, so it’s critcal on the proper gas fill and not to delay the launch.

The SAG Balloon, manufacturer is SAG, available at BalloonsOnline for around $16. If you buy 10, shipping is free, at least here in the U.S. Balloons Online 32″ Sphere

The Yokohama which is $130 for 10, but they charge $100 for freight Yokohama 32″ Transparent Sphere

Both the SAG and the Yokohama are bargains for what we’re able to acheive. As I’m writing this section we are currently flying Pico Balloon AA6DY with a Yokohama Balloon for 32 days, circumnavigating the globe is the first 22 days.

We started using Helium gas in the beginning of our program and found the gas to be reliable but very expensive. We switched to Hydrogen starting in December of 2021.

Our current package of tracker, solar panels and dipole antenna weigh 9.2 grams.

below is from our December 22nd Launch using a 36″ Chinese pancake and Zachtek tracker.

The science behind the launch, is it a roll of the dice or keep on trying till it works. KD9ORR was launched on Dec 22 at 17:30 zulu. That’s the official launch that didn’t wind up in a tree or on top of a baseball backstop. These are the calculations to determine Hydrogen fill in the balloon. Here are the pieces, Turnbuckle, Board modified with one small and one large solar panel, 1/2 line (we decided we didn’t need fishing line attached to the bottom antenna) and Dipole (33 feet 36 gauge wire) On the bottom of the page is just for information only. We were only using the clear balloon that turned out to be heavier than our previous launches, the clips are just to weigh the package on a gram scale not used in the tracker package.

So, two launches;

First one at 17.3 grams and 4.0 grams of free lift, resulted in a failure to launch, even with 3 football fields, this would have been hard pressed to lift with the wind gusts.

Second one, same day, 18.2 grams and 6.0 grams of free lift, is a success, now coming on 5 days of flight

Why the heavier package in the second one? your guess is as good as mine