About two years ago, I first took the plunge into DMR radio with the GD-77, at the time it was one of the relatively few sub-$100 DMR radios that supported both UHF and VHF on the same platform. For those who are unfamiliar with DMR, there is a remarkably sharp learning curve. The programming software (CPS) that comes with most radios does nothing to ease the transition, the GD-77 also has a few particular quirks which interrupt normal reception, often requiring the radio to be put into “promiscuous mode” in order to receive programmed talk groups. If this sounds like a negative review of the GD-77, it very much is, there are some desirable features vs other DMR radios on the market, and it’s very acceptable as a difficult-to-program analog radio.

The GD-77 was a complete disappointment as a DMR radio. One of the additional problems that complicates the management of the GD-77 is the firmware/CPS software versions are highly dependent on being of a similar build and generation, without agreement between these two bits of software, a codeplug might be written to the radio, however, attempts to test would be met with esoteric messages like “Be TX Fail”. In most cases, performing a factory reset was the only way to back out of this.

Enter the OpenGD77 Project. Previously there was what was called a “community edition GD-77 CPS” (now depreciated) which worked well. However, the new OpenGD77 provides substantially more than just a less buggy programming interface, that is compatible with the existing CPS (offering the same plus a few expanded options). Most importantly, the project also includes OpenGD77 firmware which makes radical improvements to the user interface as well as the display.

There are a few downsides to the OpenGD77 firmware, the principle complaint is the firmware has it’s own static setting for the control buttons. Meaning, you can’t simply set the accessory buttons to your desired features. Here is the firmware button mapping:

The other downside to the OpenGD77 Firmware is you lose the capability of accessing the encryption features of DMR. Not that these features are particularly strong, and yes, there are very valid points to turning this feature off as far as international compatibility (a lot of countries have put key escrow regimes into place fairly recently) as well as here in the US encrypted communications over amateur radio is limited to a single case by the FCC: Satellite control.

With all of that said, the OpenGD77 Firmware is worth checking out if you happened to buy a GD77 and haven’t been very happy with it’s performance. It really breathes new life into the radio and fixes a lot of long-standing issues I’ve had. The instruction manual provides a very good tutorial for how to install the new Firmware, and rather than duplicating any of that effort here, I suggest referring to the manual, as I’m positive some of this process may change with time.

  • Open GD77 User Guide
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    There has been a rather long-running struggle for some of us to really adopt open-source from start to finish. For a while this was fairly easy as many requirements weren’t that intensive, the basics of having network access, a web-browser, an irc client, and a shell were easily met by distros of linux that were common in the early to mid 1990’s. For a while Linux, BSD, and Solaris were usable as desktops, then that changed as requirements and specialty applications needed to drive hardware and high-end computing applications (CAD, Radio, CNC etc) were needed.

    Open Source has been displacing a lot of formerly paid applications, two notable examples, CHiRP and fldigi have been go-to applications for windows, mac and users of select linux distros that had good support for them (Ubuntu being a good example). However, for those of us whose tastes are a bit more ascetic windows XP on older hardware was the common option.

    For a while the ascetics have been searching in the darkness, looking to escape both the bloat of Ubuntu, Debian, and Redhat based systems to find something that was more efficient, freeing us of the tyranny of SystemD. Well, this was finally delivered with FreeBSD 12.

    Without a lot of time for endless exposition which will be talked about in a later article. A CentOS system was snuffed out, and replaced with a bit of struggle with FreeBSD-Stable (12). After some testing, some starts and stops, a few re-runs of the installation tools, and a few other fights, FreeBSD is up and running, configured, and is running the applications desired with a minimum of fuss.

    Here is CHiRP up and running on FreeBSD, Afterstep window manager with some basic tweaks. The best thing here, the programming cable for the UV5R simply worked. There was no need to tweak drivers, serial ports, or other headaches that have often been a problem in the past. Being able to offload administrative overhead just to get work done was kinda’ve a promise that Linux was never able to keep. As soon as you wanted to get away from the recipes in the cookbook, everything went to hell.
    After pulling down the settings that were already on the radio, it was re-written with a new codeplug!

    Shown here is FLDIGI up and running. No time was put into testing yet, but just getting this far is amazing compared to some previous efforts. Later articles will deal with the setup HOWTO. This is just a victory lap.