Category Archives: Technical

New Ground Station PSU

The problem I have had issues with the BeagleBone Black turning off after a period of operation. The exact reason I’m not too sure. The rest of the electronics seemed to be on, but I admit I did not check … Continue reading

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Progress on Electronics

Progress slowed down somewhat due to work constraints, but has sped up a little. The following has been accomplished:- * Replacement of internal PCB with a custom etched PCB for the GPS and the Relay * Removal of Arduino GPS … Continue reading

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Batteries for the HAB

I have purchased two Li-ion 3.7 batteries, each with a current rating of 2000maH.  A picture of one of these batteries is below. Initial tests with the radio modules at 24 dbi (not the max of 30dbi we will use) … Continue reading

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Radio Test – 4

A radio test has recently been conducted with good results. Test was:- * 17.1km * Using Radio-ACK version of RFD900 firmware * Air speed of 8kbits/second Was able to get:- * Minimal loss of information  (not getting a loss of … Continue reading

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Ground Station Power Supply Modifications

I initially used a 3amp LM7805 regulator to provide the 5 volts to the Beaglebone Black (BBB). This regulator will not work unless the input voltage is at-least 6.5 volts. So a 6 volt battery is not much use. So … Continue reading

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Creating the Balloon cutdown Mechanism

The cut-down mechanism is an extremely important component of the high altitude balloon. Getting a reliable cutdown mechanism is something that was considered difficult. Initial thoughts were to have some external ‘sleeve’ that would wrap around the balloon throat, using … Continue reading

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Installing the new GPS Module

I’ve realised the that the current GPS module only goes up to about 18km. This is not high enough. So I discovered a module that can go up 50km. This module is different from the current one because it doesn’t … Continue reading

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Radio Test 3

I’ve devised my own firmware for the RFD900 with changes I shall not divulge here. Fortunately the changes have been effective. I’ve been able to download an image 4.5km away in 8 minutes. The link was substantially more stable. It … Continue reading

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Testing of Radio Components

The project has stalled some what as I test and become accustomed with the new RFD900 modems. Many problems have been discovered during the testing of these modems. 1. There seems to be issues at low bauds with TX (I … Continue reading

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More improvements to the web interface app

I’ve managed to add functionality to the page to display they mobile phones GPS coordinates on the web page on the status page. I’ve also coded the status page to calculate a few interesting numbers. 1. The distance (Across the … Continue reading

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