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[WE6EE]

I've been experimenting with using a Raspberry Pi to remotely control my IC-7300 and forward audio. Remote control works nicely. Audio is a bit harder, but I'e gotten some middling success sending audio over sockets, too.

However, one issue I've been worried about when operating remotely is the chance of locking up the rig / computer / USB / network while transmitting. I've had this happen in the past due to RF in the shack. I've resolved that issue, but I got to thinking that it is hard to honestly say that my station was really compliance with the FCC regs, named: 47 CFR 97.213.

So I decided to design a simple "peripheral" for an RPi that switches the input power to my rig. I've got it working and am quite happy with it, and was wondering if anybody here would be interested in seeing it as a bare board, kit, or finished unit. In any case, I'll put all the design files up on github. Electrically, this board is simple, but it does reasonably neatly solve this niggly problem.

Some pics:






A bit more description:

https://github.com/djacobow/rigminder2

Anybody think this is interesting?

Best,
Dave
WE6EE

[WE6EE]

Because of the overwhelming show of interest from this group and others, I'm not going to try and sell or kit this device. Instead, the design files are up on github if anybody wants to build one.

https://github.com/djacobow/rigminder2

Best,
WE6EE

[N3QE]

A variety of homebuilt and adapted-commercial circuits have been built by hams to remotely reset power, or automatically reset power in case of ping test failure.

In years past they used to be available to monitor serial traffic and do a 120-reset when a watchdog expires. The more recent ones don't support serial but do Ethernet ping tests. I don't know of any that are specifically for 12VDC applications but they might be out there.

Clearly in your case you know not just "look for serial traffic" but you also know what kind of traffic to expect from a radio, so you can shape your watchdog detection exactly for the application. Great job!

One example for Ethernet-capable "120-resets" is http://webpowerswitch.com/. I think they have DC variants too (48V for telco?), but have mostly used the AC units.

[WE6EE]

Thanks for the note, N3QE. I was not aware of the commerical products for this very application. I knew there were remote power switches (I even have one I took home from work) but as far as I know it did not have a watchdog mode.

I still think having something that is ham-specific and very hackable is nice, and I really like that I have it connected directly to a Raspberry Pi. That computer is quite powerful. For example, I have an IC-7300, which puts audio and serial over USB. The RPi has USB ports, so I just plug it in, and boom, I have serial that I can remotely access over the RPi. I can remote into the RPi and run ham radio apps directly on it, or I can forward the serial and audio to another machine and work that way. The nice thing is that a little $35 computer that draws < 5W is the whole business: remote access and watchdog. If you want more serial ports, to control other devices, you can also use the RPi's built-in serial port, or plug in more serial devices to the USB ports.

Forwarding serial over IP works well, and of course, if I'm forwarding it, I can easily snoop it and use that to ping the watchdog as you suggest. Forwarding audio over IP works OK for me on the home LAN, but not great over the Internet. I think this is because the software I'm using (pulseaudio) does not do any kind of compression/transcoding, nor is it tolerant of variable delays and dropped packets. I'm going to keep looking for a better solution.

That said, everything works surprisingly well, except for the fact that some ham software just isn't that great on Linux.

Regarding switching DC vs AC, I like having both, and am glad it occurred to me to make the DC connections powerpoles. In fact, I think I will make another version of this board with two or three switches DC outlets rather than one. Then I can power on individual rigs and accessories independently.

[N3QE]

I still think having something that is ham-specific and very hackable is nice, and I really like that I have it connected directly to a Raspberry Pi. That computer is quite powerful. For example, I have an IC-7300, which puts audio and serial over USB. The RPi has USB ports, so I just plug it in, and boom, I have serial that I can remotely access over the RPi.

Yes, certainly, the Raspberry Pi is a wonderful way to put little smart projects together. I myself use a Raspberry Pi with WiFi, as a remote antenna relay driver and am super happy.

I can remote into the RPi and run ham radio apps directly on it, or I can forward the serial and audio to another machine and work that way.

Now that's very interesting. I'm OK at regular socket/port networking and in fact have used regular terminal servers at work for a good chunk of a century now. But what software do you use to forward serial to another machine and make it look like a COM port on a Windows machine? I'd love to learn how to do that.

That said, everything works surprisingly well, except for the fact that some ham software just isn't that great on Linux.

Ah, maybe you're using Linux for everything where serial port access via telnet is a no-brainer. What I need help with is Windows where it has to show up as a COM port otherwise typical ham software won't even try to access it. I have had some success running Windows inside a virtualbox on the Linux machine and it's been a while since I've done that but maybe I should go back to it.

Regarding switching DC vs AC, I like having both, and am glad it occurred to me to make the DC connections powerpoles. In fact, I think I will make another version of this board with two or three switches DC outlets rather than one. Then I can power on individual rigs and accessories independently.

Yes, powerpoles are a real win for DC power distribution in the hamshack!

As long as we are talking about Pi's and powerpoles, do you run your Raspberry Pi off of 5V wall Warts, or do you use a regulator to run it off of shack 12V? I built my own little switching regulator to run my Pi off of 12V but if there was a prepackaged unit you recommend I'd like to try it.

Tim.

[WE6EE]

Now that's very interesting. I'm OK at regular socket/port networking and in fact have used regular terminal servers at work for a good chunk of a century now. But what software do you use to forward serial to another machine and make it look like a COM port on a Windows machine? I'd love to learn how to do that.

I don't have it working on windows. On linux, I used socat on both ends. It works great. I have heard of there being a socat binary for Windows built on cygwin, but I've never tried it.

Another option is to try forwarding the USB port itself. I experimented with this as well, on Linux, and got somewhere with the serial port, but nowhere with audio.

Ah, maybe you're using Linux for everything where serial port access via telnet is a no-brainer. What I need help with is Windows where it has to show up as a COM port otherwise typical ham software won't even try to access it. I have had some success running Windows inside a virtualbox on the Linux machine and it's been a while since I've done that but maybe I should go back to it.

Agree, this would be ideal. Maybe I should try socat for windows. Alternatively, I could just break down on write a com-port to socket wedge. I know that you can access sockets and com ports on windows from Node, Perl and Python, so this sort of thing can probably be accomplished in not too many lines of code. I'd be inclined to do one end from Linux so I can stick with the Pi on the radio end and the other end for Win. I'll add it to the to-do list.

As long as we are talking about Pi's and powerpoles, do you run your Raspberry Pi off of 5V wall Warts, or do you use a regulator to run it off of shack 12V? I built my own little switching regulator to run my Pi off of 12V but if there was a prepackaged unit you recommend I'd like to try it.

My watchdog board can either make 5V from the 12V input, and use that to power the board and the Pi, or it can take 5V from the pi and power the board. I've run it both ways, but I actually prefer to do the latter. This way when I am away from my shack the only piece of powered equipment is the RPi. I don't have to leave anything on, including the 12V PSU and my Windows PC, which I can also control with the AC output of the watchdog. This means the only thing that stays awake and on and open to the world 24/7 is the ssh port on the Rpi. Everything else is OFF.

Also, I used a linear reg for 12V to 5V, because I was afraid a switcher would make noise, but it probably would have been fine. And the linear reg dissipates a lot of heat and needs a big heatsink. If the Pi draws 1A that's 7W in the regulator.