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Project Introduction

Thomas Parry edited this page Apr 18, 2020 · 1 revision

Goal

The goal of this project is to produce open-source Digital Multiplexing Transponders (DMTs) for the Amateur Radio Service Microwave Bands. These DMTs will be suitable for deployment in Geostationary Orbit. In addition, the project will produce a low-cost modem for use with these transponders. The communications systems enabled by these efforts are intended to greatly enhance the purposes of the Amateur Radio and Amateur Radio Satellite services.

Open Design

This project is entirely open-source. All of the work product will be placed into the public domain. Participation in the project is open to all. The project will prohibit the use or incorporation of any technologies that are not already in the public domain or available for unrestricted use. All contributed work is intended to be classifiable as technical data in the public domain under the U.S. export control regime (ITAR 120.11).

The Open Source Hardware Dilemma

Open source development can be fairly described as a free-for-all where talented people can find an “itch” and scratch it. This individual-centric process has produced phenomenal results. However, when the end-goal is a fully refined product, the open source process alone is often insufficient. There are many development tasks required to deploy a fully finished hardware product. Many of these tasks do not generate an itch that anyone is willing to scratch. This is the case with some of the state-of-the-art technologies involved in this project. Refining these technologies into fully productized form will require a highly focused multi-disciplinary engineering effort. The projects will have to be driven to the final goal – they won’t just arrive there on their own.

Stated another way, open source and commercial/aerospace/military development efforts have radically different definitions of “done”. In the open source world, “done” is when you throw it out to a git repository and let people start running it and playing with it. This is what drives open source. Put it out there; get feedback; refine it; put it out again; fork-it, etc. The end results can be great. But you just can’t throw something into space and wait for feedback. You can harness open source for various component pieces, but in the end, you need to deploy a fully working and tested system with very high confidence that it will work out of the box as desired, despite the hazards of space, for many years.

A major problem with complicated volunteer engineering projects is that while it is possible to find qualified individuals willing to volunteer significant amounts of their time, it is very rare to find those who are also willing to self-fund major projects or to contribute expensive equipment and software-based tools. This is especially true with complicated engineering activities that involve target equipment costing thousands of dollars and test equipment costing even more. A second problem is that these engineers are often motivated only when the prospects for eventual success are high. The engineering mind is accustomed to accepting technical risk as this is something that is, at least theoretically, under its control. Financial risk, however, is another matter – something the engineering mind attempts to avoid. Engineers whose time is very valuable may enjoy building windmills – but they don’t tilt at them. The likelihood that the project will be seen through to completion can be critical in motivating the volunteer engineering talent required to reach the final goal.


The information here has been taken from the P4XT Digital Multiplexing Transponder Project Program Proposal (draft)