Notice: Raspberry Pi based D-Star network

Regarding phone and telephone down, that was probably localized. The infrastructure held up well in the bay area. Radio and TV were still working. Well KGO had a bent tower, but it still worked.

If the R Pi is the answer, it must be a funny question. The device fails often. No serious person would use a R Pi in a public safety application.

I run a number of Raspberry Pi systems 24/7, and don't have problems with them; the only time they get restarted is when a kernel update requires a restart.

The vast majority of the Pi problems (that I've seen) are self inflicted by poor power supplies. Early versions of the kernel and particularly USB/Ethernet had problems, but those were remedied long ago. If you use a quality 5V supply, use a name-brand memory card, and don't hot-plug USB devices, you won't have problems.

Would I use a Pi in a public safety application? Probably not. Do I run them as production systems on my network? Yes, without issues.

The D-star network is a distributed system of nodes to get messages through. If a node fails, another takes up the slack. Since this is all volunteer, you can't dictate what they all use. This is an email relay system, so I don't think "public safety," whatever that is, is an issue.

Incidentally, listen carefully now, the internet or parts of it has just been handed over to the UN. It's an unfolding scenario, but I've heard that North Korea and Iran have the same vote as the U.S. in this issue of internet governance. Your freedoms may not last.

So as a result, I wouldn't mind a messaging system that I am free to use and that can't be censored or shut off. That reminds me of an incident I experienced. I was learning Chinese by talking with some attractive ladies in China on Skype. It's a nice way to learn, as you get the pronunciation down, and can correct the partner in English as well. So I inadvertently used the word "democracy," and a military-looking official broke into the Skype conversation and reminded me that was forbidden. Those are the people the U.S. has just turned the internet over to.

So, in case of emergency, a private net separate from the infrastructure sounds pretty damn good to me!!!

JB ex-K2VDO

Then again, the Beaglebone Black is good enough that Flightradar24 built their network around them.

Now originally TI didn't want Beagle products in commercial applications since the manufacturer was getting a price break. I'm not sure how flightradar24 got around this.

JB-

This may be true in some areas, especially in places like California. However D-STAR systems near me are mostly interconnected over the Internet. What you describe sounds more like a traditional Packet Radio network.

Are you referring to D-RATS rather than D-STAR? I do not think it would work for me with a radio-only data network, since the only nearby D-STAR repeaters are beyond my antenna's range.

What is the function of the Raspberry Pi? Why would you not use an existing home computer running terminal software?

Fred K4DII

Fred, This is primarily a thought experiment at this point. The use of the Pi is just arbitrary, and it's advantage is it is small and easy to power by solar cells. DRATS, etc. is a jumble of scronyms to me. I am still learning, and animated by the vision more thn the realities at this point. Can you suggest sources of info? As far as the range, the 2m is limited, so something

JB-

Perhaps the Pi would be good for its low power, especially if you have an LCD display panel with it. Otherwise a laptop computer might be a good choice, although more expensive.

You may already be familiar with websites dealing with DSTAR, such as and . These have links to other sites as well.

DRATS uses DSTAR, and seems to have much of the capability of Packet Radio. See . It is a fairly new field, and may eventually take over the data needs for Emergency Operations as the number of users increases.

For traditional Packet Radio, which sounds like what you are trying to accomplish, look at the Tucson Amateur Packet Radio (TAPR) website, . Packet networks are already in existence, and work much like the description in your first message.

Fred

JB-

With the existing Packet Radio network, the 144 MHz (2 Meters) band is commonly used. The 220, 440 and 1290 MHz bands are often used for "backbone" links between cities. Stations operating Packet Nodes transfer data between the backbone and local users on 2 Meters.

Packet Radio on 2 Meters uses a data rate of 1200 Baud. Actual data transfer is much slower, since each packet must be acknowledged before the next is sent. Packets are repeatedly transmitted until acknowledgement is received, so you are guaranteed the message will eventually get through.

Yes, the HF frequencies including 20 Meters may have greater range. However, the data rate on HF is limited to 300 Baud. Also, links between any two points can not be guaranteed since they depend on varying ionospheric conditions. HF Packet is OK for hobby communications, but not for Emergency Operations.

One neat thing about Packet Radio, is that a Packet station can be used as a repeater, even without the owners knowledge. You can communicate with someone beyond your range, if there is another station that you both can reach. I do not know if D-RATS has that capability.

Fred

Thanks for info. I frankly am a newbie to this area. I imagine any packet system can be configured for repeater network mode. I imagine it would require location information for the repeaters. But how to route in a circuitous way around obstacles and gaps I do not know. Very interesting. j

Oh, I hadn't realized the R Pi is perfect.

It is the Beagleboard that is buggy. The Beaglebone Black seems fine. I have one on my desk running 24 and 7. Like I said, flightradar24 uses the BBB in their ADS-B receivers.

Good, I'm glad to hear it. I have heard so many complaints from BB developers, I got spooked. Probably the Pi people have more "maker" for dummies type outreach, though. Yes, my wording is strange even to me, who said it. :) I glommed onto the R Pi mainly because it has a 5 mp camera all set to go. Also, I could get cave man directions for doing a myriad things with it. The main complaint I have about it is the lack of ADC.

Can you say what the advantages are over the Pi, in your view? Then I may reply, as I am fairly familiar with the Pi.

an agnostic jb

No, it's a good thing. no more USA banning domains it's owners don't like,