Steve, I find it interesting that in the same issue you mention VaraHF/VaraFM (in the 'EastNET Quarterly Videoconference on 2024-03-14' section): "the primary use of VARA HF was not for networking per se, but moving messages regionally between Bulletin Board Systems", and later on you write: "Novel (to someone) modulation methods are not encryption, as long as you’re prepared to prove that the modulation’s intent is not “obfuscation” of the content, and that the content can be recovered using a typical example of the system (or published protocol, or algorithm)."
As far as I know Jose Alberto Nieto Ros, EA5HVK hasn't published a recent specification of VaraHF. The only one I was able to find is an 8-page word document from about 7 years ago, and it begins with this sentence "VARA HF Modem is a propietary (sic) system developed by Jose Alberto Nieto Ros EA5HVK and can be used under shareware license."
Perhaps in my search I missed something, but I don't think that that Word document qualifies as a 'published protocol', that would allow a third party to recreate a new implementation of VaraHF/VaraFM without reverse engineering EA5HVK's software.
Zombie Apocalypse: Over here in Germany we are faced with power grid problems even more: Beginning with the Merkel government politics has started to destroy our power infrastructure to fight climate change. We have switched off all atomic power plants. We switched off many coal power plants to be replaced with gas power plants that nobody wants to build for obvious reasons - even before Putin switched off our most important gas supply. Socialist/green ideology first destroys the infrastructure and then gives a bit of thought where power should come from at night when there is no wind. Nobody gives a thought to the fact that a power grid needs conventional power plants to "iron out" momentary fluctuations.
Since 2018, I have experimented with solar and batteries. About the biggest problem are the DC currents: If you have a 12 V system and want to integrate a 2 kW inverter, you must cope with up to 200 A of current! Suddenly you must try to create contacts with resistances of 1 mOhms or so.
If you simply want to charge battery-powered equipment from flash lights to cell phones or radios, It is easy: Get a 100 W solar panel, a charge controller and a 20 Ah or so battery. Any lead-based batteries are good if you can get them used for next to nothing. Otherwise you should go the LiFePO4 route. Their prices at least halved over the last two years.
If you depend on equipment that need a mains supply, a "power station" from Ecoflow etc. is a simple and relatively cheap solution. But keep in mind that a 2 kWh power station typically contains a 2 kW inverter, that consumes around 25 W by itself - even if nothing is connected. Do the math how long this power station will work.
Most of these power stations also have 12 V and USB outputs. The switching regulators used here have much lower losses. But problems remain:
* No manufacturer I know defines the "12 V". Luckily my power station provides 13.2 V, meaning I can easily operate my ham radio equipment from my power station.
* 100 W/8 A is not much. You are limited to a QRP station and a notebook computer.
* The measurement circuitry in the power station has "full scale" measurement ranges according to the rated output, e.g. 2 kW. If you draw for example 30 W for two days, the charge measurement gets extremely unreliable. My power bank did a low-power switch-off at a charge display of 35%.
Thanks for the mention Steve! And that LimeNET Micro 2 looks pretty neat. I'm looking for some kind of Pi related kit to hone in on malicious radio operators. Have you covered anything in the past?
I bought a PV solar system on my house a few years ago for the tax break and to "prepay" my electric bills for the next 10 years. I have no intention of moving at this time, but PV is one of the home improvements that generally will add some value when the house is sold. I looked at several options for batteries, including Tesla Powerwall systems that my electric co-op was offering at a substantial discount if I allowed them to use some of the stored power during peak time. I ended up with a brand name DC system (optimizers vs micro inverters is something to consider) that had a battery back up option. At the time I was buying the battery had issues and was under a recall. And it was just after California had revoked their net metering laws so utilities could pay wholesale rates to solar customers instead of retail, leading to a big push for batteries.
Anyway, the DC side of my system runs at 480 volts (nominally 400). This helps keep conductor sizes reasonable, but also means you can't just tap off it for charging up a couple of Battlebornes for your shack. I also have an old telecom -48VDC rectifier/inverter and battery string for my shack. Probably not as efficient as keeping everything 12 Volts but the price was right and it supplies 3.2 kW continuously to my shack, home network and several computers in a fairly small package. In contrast, my old 12 VDC system that did the same thing heated the room too.
Thanks for the mention Steve! Your defense of old TNCs is more than fair, and to be clear I wasn't knocking them, The KAM+ was just at the top of my "TNC Museum Pile" when I was writing it. There is no way anyone is doing modern crypto on one of those old Motorola chips, or worse yet a Z80 in a TNC2 clone :-)
I grew up on a dairy farm in rural Wisconsin where day-long power outages happened at least once or twice a year. Multi-day outages were less frequent, but not unheard of. Every farmer had at least a 25kw PTO generator they would hook to their most efficient tractor and unless it was during planting or harvest time there is probably a week of fuel available in the tank (often gravity fed). About 10 years ago my dad put in a grid-tie solar system, mainly as a way to offset energy bills. I've never asked him what happens if that is producing power at the same time the generator is on. I can't image it would be good if that happened since the generator would have much lower overall resistance than a functioning power grid. I'll have to ask him next time I'm over there.
The piece on transmission schedule broadcasting brought back some good, and bad, memories. I did my masters back thesis in 1985 on the topic of techniques to improve radio channel utilisation. Then, I adopted the approach used by (the newish) IEE802.3 Ethernet: i.e. collision detection. I may well go back and look at my stuff from then - if I still have it - and maybe try again using the approach posited in the article. It might keep my grey matter working for a bit longer…
Your Tesla power wall phone home is old information.
Steve, I find it interesting that in the same issue you mention VaraHF/VaraFM (in the 'EastNET Quarterly Videoconference on 2024-03-14' section): "the primary use of VARA HF was not for networking per se, but moving messages regionally between Bulletin Board Systems", and later on you write: "Novel (to someone) modulation methods are not encryption, as long as you’re prepared to prove that the modulation’s intent is not “obfuscation” of the content, and that the content can be recovered using a typical example of the system (or published protocol, or algorithm)."
As far as I know Jose Alberto Nieto Ros, EA5HVK hasn't published a recent specification of VaraHF. The only one I was able to find is an 8-page word document from about 7 years ago, and it begins with this sentence "VARA HF Modem is a propietary (sic) system developed by Jose Alberto Nieto Ros EA5HVK and can be used under shareware license."
Perhaps in my search I missed something, but I don't think that that Word document qualifies as a 'published protocol', that would allow a third party to recreate a new implementation of VaraHF/VaraFM without reverse engineering EA5HVK's software.
73,
Franco Venturi K4VZ
Zombie Apocalypse: Over here in Germany we are faced with power grid problems even more: Beginning with the Merkel government politics has started to destroy our power infrastructure to fight climate change. We have switched off all atomic power plants. We switched off many coal power plants to be replaced with gas power plants that nobody wants to build for obvious reasons - even before Putin switched off our most important gas supply. Socialist/green ideology first destroys the infrastructure and then gives a bit of thought where power should come from at night when there is no wind. Nobody gives a thought to the fact that a power grid needs conventional power plants to "iron out" momentary fluctuations.
Since 2018, I have experimented with solar and batteries. About the biggest problem are the DC currents: If you have a 12 V system and want to integrate a 2 kW inverter, you must cope with up to 200 A of current! Suddenly you must try to create contacts with resistances of 1 mOhms or so.
If you simply want to charge battery-powered equipment from flash lights to cell phones or radios, It is easy: Get a 100 W solar panel, a charge controller and a 20 Ah or so battery. Any lead-based batteries are good if you can get them used for next to nothing. Otherwise you should go the LiFePO4 route. Their prices at least halved over the last two years.
If you depend on equipment that need a mains supply, a "power station" from Ecoflow etc. is a simple and relatively cheap solution. But keep in mind that a 2 kWh power station typically contains a 2 kW inverter, that consumes around 25 W by itself - even if nothing is connected. Do the math how long this power station will work.
Most of these power stations also have 12 V and USB outputs. The switching regulators used here have much lower losses. But problems remain:
* No manufacturer I know defines the "12 V". Luckily my power station provides 13.2 V, meaning I can easily operate my ham radio equipment from my power station.
* 100 W/8 A is not much. You are limited to a QRP station and a notebook computer.
* The measurement circuitry in the power station has "full scale" measurement ranges according to the rated output, e.g. 2 kW. If you draw for example 30 W for two days, the charge measurement gets extremely unreliable. My power bank did a low-power switch-off at a charge display of 35%.
For more information see my Web site: https://www.dl4no.de/thema/notstro3.htm - use Google Translate etc.
Thanks for the mention Steve! And that LimeNET Micro 2 looks pretty neat. I'm looking for some kind of Pi related kit to hone in on malicious radio operators. Have you covered anything in the past?
I bought a PV solar system on my house a few years ago for the tax break and to "prepay" my electric bills for the next 10 years. I have no intention of moving at this time, but PV is one of the home improvements that generally will add some value when the house is sold. I looked at several options for batteries, including Tesla Powerwall systems that my electric co-op was offering at a substantial discount if I allowed them to use some of the stored power during peak time. I ended up with a brand name DC system (optimizers vs micro inverters is something to consider) that had a battery back up option. At the time I was buying the battery had issues and was under a recall. And it was just after California had revoked their net metering laws so utilities could pay wholesale rates to solar customers instead of retail, leading to a big push for batteries.
Anyway, the DC side of my system runs at 480 volts (nominally 400). This helps keep conductor sizes reasonable, but also means you can't just tap off it for charging up a couple of Battlebornes for your shack. I also have an old telecom -48VDC rectifier/inverter and battery string for my shack. Probably not as efficient as keeping everything 12 Volts but the price was right and it supplies 3.2 kW continuously to my shack, home network and several computers in a fairly small package. In contrast, my old 12 VDC system that did the same thing heated the room too.
Thanks for the mention Steve! Your defense of old TNCs is more than fair, and to be clear I wasn't knocking them, The KAM+ was just at the top of my "TNC Museum Pile" when I was writing it. There is no way anyone is doing modern crypto on one of those old Motorola chips, or worse yet a Z80 in a TNC2 clone :-)
I grew up on a dairy farm in rural Wisconsin where day-long power outages happened at least once or twice a year. Multi-day outages were less frequent, but not unheard of. Every farmer had at least a 25kw PTO generator they would hook to their most efficient tractor and unless it was during planting or harvest time there is probably a week of fuel available in the tank (often gravity fed). About 10 years ago my dad put in a grid-tie solar system, mainly as a way to offset energy bills. I've never asked him what happens if that is producing power at the same time the generator is on. I can't image it would be good if that happened since the generator would have much lower overall resistance than a functioning power grid. I'll have to ask him next time I'm over there.
The piece on transmission schedule broadcasting brought back some good, and bad, memories. I did my masters back thesis in 1985 on the topic of techniques to improve radio channel utilisation. Then, I adopted the approach used by (the newish) IEE802.3 Ethernet: i.e. collision detection. I may well go back and look at my stuff from then - if I still have it - and maybe try again using the approach posited in the article. It might keep my grey matter working for a bit longer…
Gareth, M5KVK