Modified SPOT tracker that runs for months

Modified SPOT tracker that can run for months


Developer GPS Guided Trans-Atlantic Robot Boat  has produced a control box to work with a SPOT v1 tracker to extend it’s function to months. The unit was designed to track a trans Atlantic model boat but can be used in balloon missions. Robin, the designer from the UK said”  We are doing 24/7 testing at a waypoint in the corner of Bray Lake on the boat. This is helping us solve basic problems like finding leaks and proving the total boat system, including solar panel based power systems, GPS-PICAXE-rudder servo autopilot, SPOT tracker, and the boat itself. The SPOT tracker enables us to monitor the boat from home – particularly if it runs aground. See the SPOT map for recent position reports.

On low left you see a very crude means of making the SPOT Messenger send regular position reports, currently every hour. A PICAXE based timer (on left) operates a servo to press the “OK” button on the SPOT to initiate a position report. The small loudspeaker is just for test – to play “Popeye the sailorman” just before transmission 🙂 A tidied up version of this SPOT tracker, was put in boat 8 for 24/7 tests on Bray Lake, until the SPOT Messenger eventually failed, after months of continuous operation. We now have a Mk2 version in the boat that does not need a servo. It has also been running for months.

My spot tracker is a self-contained sub-system. It breaks all the rules on what spot say you should do.e.g. I have Ni-Me rechargable AA cells each giving about 1.6v. In parallel with those I have 3 NiMH cells.Two 6v 80mA solar panels in parallel charging power. Picaxe off the same power as spot.This is NOT a proven solution, even though tested for months, so anyone would need to do their own experiments starting with a SPOT messenger (off ebay?) and £90/100Euro of air time.”

We hope to get more details of the box design when Robin has more time.



Another Pi reaches the Sky

A 13 years old boy has launched another Raspberry Pi powered balloon payload in Illinois, USA last month. The small computer powered a GPS sensor and pressure sensor as part of a science fair project. Read more…

Black Sky Raspberry Pi payload


A cost effective way to track and photograph from ‘one off’ balloon launch

Balloon News is now offering the hire of all the big ticket items you need to launch you one off balloon. This includes the hire of SPOT Messenger (V1 and V2), and enhanced GPS locators. Go Pro Hero 2, and the super light weight Catcam cameras can be hired too. Parachutes are also available for hire. For more information go to



Multi balloon launch in Australia to promote Go Pro Hero 3

Early next week we will be flying 15 balloons in three launches of five over two days.

The location is Rankins Springs in NSW Australia -33.8400 146.2584
Payloads as follows.
All payloads  50 baud,7 bits, no parity, 2 stop bits.
Tuesday 20th Launch at 8:00am EST
Apollo 25mW 434.650MHz 600Hz shift  (0 seconds)
Starbuck 25mW 434.650MHz 350Hz shift  (20 seconds)
Hot Dog 25mW 434.650MHz 600Hz shift  (40 seconds)
Racetrack 25mW 434.075MHz 600Hz shift  (0 seconds)
Skulls 10mW 434.075MHz 600Hz shift (20 seconds)
Tuesday 20th Launch at 11:00am EST (potentially delayed by recovery of previous launch)
Maverick 25mW 434.650MHz 600Hz shift  (0 seconds)
Iceman 25mW 434.650MHz 350 or 600Hz shift (20 seconds)
Goose 25mW 434.650MHz 600Hz shift  (40 seconds)
Viper 10mW 434.075MHz 600Hz shift  (0 seconds)
Jester 10mW 434.075MHz 600Hz shift  ,7 bits, no parity, 2 stop bits. (20 seconds)
Wednesday 21  Launch at 8:00am EST
Enterprise 25mW 434.650MHz 600Hz shift  (0 seconds)
Columbia 25mW 434.650MHz 350 or 600Hz shift  (20 seconds)
Discovery 25mW 434.650MHz 600Hz shift  (40 seconds)
Atlantis 25mW 434.075MHz 600Hz shift (0 seconds)
Endeavour 10mW 434.075MHz 600Hz shift (20 seconds)
I noticed some of the 434.075MHzc 10mW modules where down near 434.065Mhz out of the box, so you might need to hunt around a bit.
Launch site is just over 700 clicks form Adelaide and we are using mostly 25mW modules so we could see some long range tracking from the Horus crew.
Multiple Ballons and Time Series Multiplexing
Payloads are split amongst the  434.075 and the 434.650MHz frequencies, I thought about trying to be smart an play with the adjustments on the modules but  decided against it,
As recently brought up on the list we are going to be time multiplexing the telemetry. Nothing fancy really as relative HAB newbies (one previous flight) we a taking a slow an safe approach having each ballon transmit once a minute in a dedicated time slot. Time sync is defined from GPS with a fall back / emergency mode if it detects that GPS no longer updating.
One of the main thing’s that is brought up when you mention time series multiplexing is the difficulty of tracking multiple payloads with slightly different frequencies in dl-fldigi. At least on the test bench we have found that (at least under os x) simply running multiple instances of dl-fldigi works really well. Obviously would not scale very well but for a few payloads seems to work well.
Flight details 
These are short flights, not aiming for huge altitude here. 300g Totex balloons 1.5 hours total flight time bursting around 17km.
GoPro 3’s 
We got a batch of the new GoPro 3’s so we will let you know how thay work out in flight.
The funding from the flights is coming from advertising, it’s part of a launch for a premium frozen yogurt, the angle is that they use the cold temperatures at altitude to freeze their product.  So there are three temperature sensors on the payload, one internal, one eternal and one for the product.
We are a team of hackers, makers, geeks and when we where asked if we could fly helium balloons (something we had been planning to do anyway) we said sure we can. We already had a name for our group.
St Peters Aeronautical and Space Organisation (SPASO)
For more information DO NOT CLICK HERE
Justin Maynard