2025-09-26 — What’s New at DLARC — September 2025, Voice over Packet (VoP), The Software Based Future of Amateur Radio, Polar Modulation, Raspberry Pi 500+, Bridgecom Systems BCR-220 Repeaters
While it's great to see the Polar Explorer implementation, the modulation technique itself is hardly new. There is an article about this method, and the Polar Explorer, in the March/April 2017 QEX (https://www.arrl.org/files/file/QEX_Next_Issue/Mar-Apr2017/MBF.pdf). In the article it mentions that the polar modulation was invented by Thomas Edison for use in telegraphy. I believe that Hans has also implemented this modulation to provide SSB operation in the QRP Labs "QMX " transceiver.
Paul - I didn't intend to portray Polar Modulation as a new technique (and apologies to you if I did give you that impression). If I had been able to quote more liberally from the article I referenced (which isn't available in public, so I cannot) that point would have been clearer as the (unnamed) author makes the same point as you. Polar Modulation isn't a new technique... but the recent implementations of Polar Modulation - the FlexRadio Aurora and the QRP Labs QMX (you were correct) are novel and interesting technology and thus Zero Retries Interesting, and worth mention.
It's great to see that CentyLabs is moving forward. I'm very happy with my PocketPD that I paid cash for at ZRDC. (I literally saw it, pulled out $60 and said, "Take my money!") I just purchased their last version with XC60 connectors for a friend that's into drones. XC60 is the Anderson Pole Connector for the drone world. After a very nice portable op on the Columbia River (see links below) I was able to charge my LiFePo battery with the PocketPD and a small Anker 65W wallwart. Having a full display and being able to set the voltage and current is so much better that a regular charger with just an idiot light. -Joe w7com
Joe - You're right - thanks for that example of the utility of the PocketPD. I had been thinking too narrowly of its capabilities, limiting my thinking to just using it as a low current 12 volt power supply, but you're absolutely right - there are unlimited uses of it for supplying odd voltages from a standard USB C, and being able to monitor both voltage and current. I'm definitely joining the Crowd Supply campaign now for a couple of them.
At SEA-PAC 2025, I won a 1-year membership to NARA (https://amateurradioalliance.org/). It's a different org but using that same FLA (four-letter acronym).
Thanks for your word "revolutionary" to describe polar modulation. I attended Hamvention 2025 and happened to be at the QRP labs when Hans and Steve Hicks were trying to have a conversation. Hans interrupted it to take my order for a QMX+, after which I ran over to buy a Hard Rock 50. Ever since I've been repeating the "revolutionary" mantra and it has fallen on deaf ears. The ham community just doesn't get it. Wouldn't you like to hear the discussions at Kenwood, Icom, Yaesu and Elecraft? And why isn't there more discussion in other ham technical forums, podcasts and YT channels? Further, what else might I do to get hams excited about this?
John - I'm not the right one to ask about "get hams excited about this". In my view, Polar Modulation is a new, more efficient method to do classic SSB. That enables a lot more power efficient generation of SSB and that makes higher power SSB a lot more accessible. The FlexRadio Aurora generating 500 watts of HF transmit power in such a small form factor, with minimal electrical power input is really amazing.
But in my perspective, FreeDV RADE (as one example) is more interesting than Polar Modulation because it is digital voice at low power levels on HF, powering through the typical human (technology) generated noise / interference.
As I'll expound in this week's Zero Retries, all new technologies / projects / projects require a promoter... champion... evangelist to ultimately succeed in the competition for ideas in Amateur Radio. I got tired of seeing such developments being ignored, so I started Zero Retries.
I welcome guest author articles in Zero Retries, such as a future deep dive article on Polar Modulation. The article I cited was a great one which did a great job, but the sadness of that article is that it's hidden behind a paywall somewhere, and will only ever be seen by a scant few. Thus we need an equivalent article that's PUBLICLY accessible that better explains Polar Modulation.
Polar Modulation --
While it's great to see the Polar Explorer implementation, the modulation technique itself is hardly new. There is an article about this method, and the Polar Explorer, in the March/April 2017 QEX (https://www.arrl.org/files/file/QEX_Next_Issue/Mar-Apr2017/MBF.pdf). In the article it mentions that the polar modulation was invented by Thomas Edison for use in telegraphy. I believe that Hans has also implemented this modulation to provide SSB operation in the QRP Labs "QMX " transceiver.
Paul - I didn't intend to portray Polar Modulation as a new technique (and apologies to you if I did give you that impression). If I had been able to quote more liberally from the article I referenced (which isn't available in public, so I cannot) that point would have been clearer as the (unnamed) author makes the same point as you. Polar Modulation isn't a new technique... but the recent implementations of Polar Modulation - the FlexRadio Aurora and the QRP Labs QMX (you were correct) are novel and interesting technology and thus Zero Retries Interesting, and worth mention.
It's great to see that CentyLabs is moving forward. I'm very happy with my PocketPD that I paid cash for at ZRDC. (I literally saw it, pulled out $60 and said, "Take my money!") I just purchased their last version with XC60 connectors for a friend that's into drones. XC60 is the Anderson Pole Connector for the drone world. After a very nice portable op on the Columbia River (see links below) I was able to charge my LiFePo battery with the PocketPD and a small Anker 65W wallwart. Having a full display and being able to set the voltage and current is so much better that a regular charger with just an idiot light. -Joe w7com
https://wonkodon.com/@admin/115240216197810411
https://wonkodon.com/@admin/115246044904767606
Joe - You're right - thanks for that example of the utility of the PocketPD. I had been thinking too narrowly of its capabilities, limiting my thinking to just using it as a low current 12 volt power supply, but you're absolutely right - there are unlimited uses of it for supplying odd voltages from a standard USB C, and being able to monitor both voltage and current. I'm definitely joining the Crowd Supply campaign now for a couple of them.
At SEA-PAC 2025, I won a 1-year membership to NARA (https://amateurradioalliance.org/). It's a different org but using that same FLA (four-letter acronym).
Thanks for your word "revolutionary" to describe polar modulation. I attended Hamvention 2025 and happened to be at the QRP labs when Hans and Steve Hicks were trying to have a conversation. Hans interrupted it to take my order for a QMX+, after which I ran over to buy a Hard Rock 50. Ever since I've been repeating the "revolutionary" mantra and it has fallen on deaf ears. The ham community just doesn't get it. Wouldn't you like to hear the discussions at Kenwood, Icom, Yaesu and Elecraft? And why isn't there more discussion in other ham technical forums, podcasts and YT channels? Further, what else might I do to get hams excited about this?
John - I'm not the right one to ask about "get hams excited about this". In my view, Polar Modulation is a new, more efficient method to do classic SSB. That enables a lot more power efficient generation of SSB and that makes higher power SSB a lot more accessible. The FlexRadio Aurora generating 500 watts of HF transmit power in such a small form factor, with minimal electrical power input is really amazing.
But in my perspective, FreeDV RADE (as one example) is more interesting than Polar Modulation because it is digital voice at low power levels on HF, powering through the typical human (technology) generated noise / interference.
As I'll expound in this week's Zero Retries, all new technologies / projects / projects require a promoter... champion... evangelist to ultimately succeed in the competition for ideas in Amateur Radio. I got tired of seeing such developments being ignored, so I started Zero Retries.
I welcome guest author articles in Zero Retries, such as a future deep dive article on Polar Modulation. The article I cited was a great one which did a great job, but the sadness of that article is that it's hidden behind a paywall somewhere, and will only ever be seen by a scant few. Thus we need an equivalent article that's PUBLICLY accessible that better explains Polar Modulation.
Or presentations, or YouTube videos, or ???