Store and Forward episode 10 — Back to Work in 2025

Store and Forward

The video version of this episode is at: https://youtu.be/jLnpy3yQJHE

Digital Library of Amateur Radio & Communications (a project of the Internet Archive): https://archive.org/details/dlarc

Zero Retries Newsletter: https://www.zeroretries.org

Not mentioned on this podcast, but Kay recently did a presentation to RATPAC titled DLARC – The Free Online Ham Radio Library which is a great overview of the wide range of Amateur Radio (and other) material available in DLARC.

Kay discussed some interesting and specialized Amateur Radio newsletters recently added to DLARC including:

Amateur Television in Central Ohio (ATCO) – https://archive.org/details/atco-newsletter

425 DX News – https://archive.org/details/425-dx-news

What’s notable is that it has been published every Saturday since beginning publication… in 1991! (As a fellow newsletter publisher, Steve admired that level of dedication!)

DX World Weekly Bulletin – https://archive.org/details/dx-world

… and this historical magazine:

The Telegraphic Journal and Electrical Review – https://archive.org/details/pub_the-telegraphic-journal-and-electrical-review

Steve said he was pretty sure he had seen a collection of this magazine just yesterday as he was picking up some magazines at the Bellingham (Washington) Spark Museum of Electrical Invention – https://www.sparkmuseum.org.

Steve discussed a bit of the backstory of his fiction story in Zero Retries 0183 – https://www.zeroretries.org/p/zero-retries-0183 – Paying it Forward in Amateur Radio about a conversation between Jennifer, a young techie Amateur Radio Operator and Jada, a young woman in her teens about Jennifer’s Amateur Radio activities.

Steve then discussed a few of the items mentioned in Zero Retries 0184 – https://www.zeroretries.org/p/zero-retries-0184:

zBitx portable HF radio – 5 watts, Software Defined Radio, for $149 – https://www.hfsignals.com/index.php/zbitx/

SignalSDR Pro – Software Defined Transceiver with 2 TX and 2 RX for $900 – https://www.crowdsupply.com/signalens/signalsdr-pro

KV4P-HT (Kit Available from Halibut Electronics) – Open source project of a “strap on VHF radio” for Android phones – https://electronics.halibut.com/product/kv4p-ht-v2/

Steve went on to discuss the recent unveiling of NVIDIA’s Project Digits which is a “1 petaflop desktop computer” and the potential for him to “talk to his desktop AI” (that would be running on a Project Digits computer) to develop a fantasized future radio system. This combination would be the equivalent of having a full time software engineer writing GNU Radio code, and Steve just uses the output of the AI in GNU Radio, tries it out, notes what works and doesn’t work, inputs that back into the AI.

Kay said that he would love to “browse” various digital modes automatically, and Steve said that we’re close to that, including:

DragonOS – https://sourceforge.net/p/dragonos-focal/wiki/OriginStory/

KiwiSDR – https://kiwisdr.nz/blogs/news/about-kiwisdr-radios

Signal Identification Wiki – https://www.sigidwiki.com/wiki/Signal_Identification_Guide

Radios are computers – with antennas! We keep having more and more (cheap) computing power to throw at radio communications!

As an example of how abundant computer power can make a difference in (Amateur Radio) radio technology, Steve discussed the innovation of “bit flip testing and correction” that John Langner WB2OSZ implemented in Dire Wolf Software TNC – https://github.com/wb2osz/direwolf. See this presentation by WB2OSZ – https://archive.org/details/direwolf-software-tnc.

Kay joked:

If you can flip one bit and figure out what the packet is based from the CRC. Why transmit the packet at all? Just transmit the CRC and figure out what the packet should have been?

Steve said “we’re close to that”, but couldn’t recall the details during the podcast of what a Zero Retries reader mentioned in a comment that was a similar capability to what Key described.

Post-podcast:

In the comments of Zero Retries 0179, https://www.zeroretries.org/p/zero-retries-0179/comments, Louis Mamakos WA3YMH said:

Just a thought on multicast file distribution systems. There is a class of algorithms called erasure codes (https://en.wikipedia.org/wiki/Erasure_code) that take some chunk of data, run a transformation on it to break it up into blocks (the total size somewhat more than original.) Then a receiver need only receive K out of N blocks that were produced by the encoding algorithm to compute the original data. This sort of thing is used at small scale with Reed-Soloman coding and at large scale for storing files. Professionally, we used a product like this which would ingest files, generate blocks that were then stored at multiple geographically dispersed locations. By tuning K and N, you would get disaster recovery and the system overall in managing all the metadata was very scalable.

The application for amateur radio beacons and the like is to just transmit blocks and the receiver can start receiving them at any time and eventually reconstruct the original object. Some research reveals some commercial work for such a thing to be deployed on unidirectional broadcast satellite links where a reverse channel to ask for “fills” wasn’t available. Missing a block means you don’t have to wait for that one block to be retransmitted to you much later; you might still reconstruct the object sooner.

There appear to be some open-source libraries to do this encoding and decoding computation and that would then need a UI and data transport interface wrapped around it. This sounds like a great opportunity to combine ham radio and thesis work for the right person 🙂

Kay was prescient! 🙂

Kay concluded the podcast by saying that DLARC added 1.1M pages of material in 2024!