The project I have been working on actually formed out of a couple of mistakes. I got the boards in for the repeater controller and after about 2 hours of putting parts on them I discovered a couple of mistakes. One of these mistakes, routed an output signal to the wrong input, and another found a trace that hadnt been put on the board. Both were my mistakes. I learned the hard way now that if you dont run the board through an ERC error check, or like I did, went through it really fast, you end up with a board that could cause you lots of fits.....I discovered this the hard way, fits and all.......so what to do. I made the mistake, all be it, a 20 dollar mistake. So I thought about it for a while and relaized that while I couldnt use the board in the controller, I could re-purpose it for something else ( and yes I resubmitted the correct boards to the fab house.......again......
I was cruising around on the web, and found something that looked like I could have fun with. Several hams have used the concept of a private ALLSTARLINK node and taken it a step further, creating what many called the " Naked Node" The Node is nothing more than a radio link to the Allstar Network, using a simplex radio on UHF or VHF. You house the node in an open non-boxed concept leaving the internal boards and all naked to the visible eye. Many hams have done something like this including W0ANM, WA3DSP and KP4TR, you can check out their web pages via google, or search Naked Node.......
I had the extra Beagle bone black v4, the botched control boards, extra UHF handie, and a few things I needed to order. I thought, heck why not. Of course the Rich curse slowly kicked in. This went from a simple node to something I have added to and added to but hey, building is what I do, and enjoy, so if I choose to make it a bigger thing than needed, its just the way I like to have fun.
The radio was pretty easy to modify. I had a BF-888s, in fact I have 2. They are cheap, easy to part out and modify. There were some web sites that had excellent step by step instructions on how to do this.
The bottom picture shows the radio after first opening it, and the top shows the radio after the modifications. Aside from needing to pull the entire circuit board out, and some desoldering, the whole mod only took about an hour. When I was done, I could remotely key the radio and had a positive going COS ( carrier present signal) as well as both mic, and received audio. For now Im concentrating on the control circuits, so I havent fiddled with the audio just yet.
Once this was done, I turned my attention to the control board, or rather the botched repeater control board. I looked and though its a rather large board, and a lot of it will be unpopulated, I went ahead and used it, making the modifications for simplex use. Since I had designed it, fixing what I needed wasnt that bad
It doesnt look like a lot of modifying, because in reality its not. In order to make the board work, I had to add a couple of jumpers ( which I admit I hate) and removed a feed through from one module to the other. Breaking this line I had to tack solder a jumper in to reroute the signal. I went ahead to and added a Dignal line ( D9) coming from the Arduino, and ran this out an unused pin on the power plug. Im gonna use this for system power on/off.
The original repeater board has a repeater module, a control radio module, as well as a remote base module and finally a module for interfacing the USB FOB sound card to the radio. In the node setup nearly all of this will not be used. I simply modified a repeater module, and the FOB module I added a transistor switch, which Ill explain later. It actually wasnt bad as long as you document what you changed, so if anything goes wrong, you arent looking at the original schematics and wonder whats wrong....that could be bad.
Below is the first level of the naked node
The first level consists of the control circuits. I made sure I always add lot of RF filtering on the control line to stop false triggering due to RF getting in the traces.....I also decided that the control circuits will be placed as far as they can be from the radio, so the control boards are on the bottom. You can see as I mentioned alot of this board is unpopulated. The small module that plugged in is the repeater module. To the left of that is the arduino micro mini microcintroller. This is used in the repeater, for the node Im gonna have to rewrite the firmware to make it a simplex operation. The Micro Mini will be just used to run other things, like onboard control, power monitoring, and such. Since its only doing a fraction of the work it would in a repeater, Ill use it for other fun things.
The next level is the computer
Shown here before mounting is the BBBv4. The heart of the VOIP system. Its running a version of the ALLSTARlink software and not shown is the modified USBFOB soundcard. The sound card is also modified, and Ill show that later as well.
Thas it for this post, the next 2 layers will be next including the final radio install and the surprise....!
Stay Tuned...and Happy coding!
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