APRS system build

For the first flight, we built an APRS system consisting of the BARBE_1 transmitter, a TinyTrak3, our home built 2-meter dipole, two LiPo batteries, and a small GPS module from SparkFun. The following picture shows them all wired together..

aprs_system_1

and here is some captured data sent from the system:

aprs_data_01

Custom Radio Module

I decided to try my hand at building my own transmitter module. I did this mostly to save weight rather than lofting a heavy handheld radio. The Radiometrix 300mw HX1 radio seemed to be a solution that worked for many,  so my brother and I bought three of them and proceeded to design the custom radio module.

I started with some simple design goals:

  • Low battery voltage cutoff feature
  • Interface that matches the TinyTrak
  • Pre-emphasis circuit to compensate for the digital only nature of the transmitter module
  • SMA output

Circuit Diagram

balloon1_m

 

The journey begins….

In this Blog, I chronicle my experiments with High Altitude Ballooning.

My name is Jerry (K3JLE), and earlier this year, my brother Steve (K3SWE) and I decided to replicate what many have done before. To fly high altitude balloons to the edge of space using ham radio equipment for tracking, telemetry, and recovery of the experimental equipment.