The Power of the Screwdriver

I will be the first to admit that I am not an electronics genius. I got into radio because I wanted to learn more, and I am glad to report that I have gained a great deal of practical knowledge about electronics and radio. Within the NSRC Board, we have had discussions about the right way to teach people about radio. I have a perspective that I don’t think we have ever considered that I would like to add here. First, to summarize the pedagogical arguments: one school of thought is that you teach general concepts and the details will follow; the other idea is that you teach the essentials you need to learn to pass the exam and the details will follow. I have to admit in my own education, I largely followed the latter path, because I was impatient. To learn more of the formal theories used in our hobby, I have resorted to building small kits (studying schematics) and reading books. This model has worked fairly well for me.

So my alternative suggestion? Plug and Play, with an emphasis on play. If you can start by experimenting, working on practical problems you can reach the same end (and you will probably blow a few things up along the way as well!). For instance, I truly believe the real value of a becoming a ham radio operator has been what it has taught me about problem solving. I feel empowered to use my screwdriver to explore the world under the metal cabinet. What happens when the SWR is too high? When your amp does not put out power? When the mic audio is distorted? When the ladder line you deployed throws RF back through your system and bites you every time you key up the mic! These are all practical problems that I have had to manage most recently, but this goes by extension to other things as well. Like Life!

I recently bought a new computer for my shack that just was not working. It kept crashing. I had all sorts of advice from my Internet friends and buddies in the club. Slowly, I discovered the problem and it was not an intuitive fix. Turns out the guy who built the machine installed the jumper cables for the serial ports in backwards (there was not key pin on the jumpers, so the error could have been made by anyone.) Once I reversed the cable, the problem went away. Now, this took weeks of thinking, observing, experimenting and writing down what was going on: when did the error occur? What did I do to get the system to recover? I even took it back to the shop and the guy refused to work on the machine! He said, “Hardware never fails…and I would have to charge you!” Finally, I got bold and decided to take the serial card out myself and that was when I found the problem. I learned a long time ago to try, and if you fail, then you can bring in the Marines to save the day.

The other day, Ron Settle WM9Q and I went to visit our ailing 220 machine. We opened the cabinet and immediately discovered that the power supply was dead. This was not the problem we were expecting. Ron had brought fuses for every other component but the power supply because, frankly, how often do those go down? In my rather short ham life, I have yet to see a power supply go bad and this was a brand new unit (and here’s the rub…brand new!! BEWARE). What I watched next truly amazed me….and I think it did the same for the gentleman from the building who accompanied us to the site. Ron fully demonstrated the power of a screwdriver in the hands of a ham radio guy. Ron wanted to see if there was something in the system that was causing the power supply to fail, but he did not have the correct sized fuse, so he fashioned a jumper using one of the longer fuses he brought along that had the right rating. With the jumper cable and some electrical tape, he cobbled together a temporary fuse (Editor: never use your screwdriver to bridge the fuse…that is not a fuse. It is a great way to start a fire. More on that in another blog!!) In an instant, he had built a “work around for the fuse,” so now he could power the repeater and better trace where the problem might be. Then, he put out a call on his radio to see if the repeater worked. It worked fine. However, we noticed that the cooling fan on the power supply was not turning. Clearly, that was the failure point, and the heat sink on the supply was growing quite warm in a very short period of time. So we decided to take the power supply out and work on it at home. He followed this simple process: Observe; test systems logically – power, transmitter, controllers, amps, and antenna; experiment; and conclude. Following this logic tree, we discovered a few other problems with that repeater that need to be addressed in the future as well.

I was very proud of how quickly the problem was sorted out, a solution presented and a recovery plan discussed (we will be putting in backup power supplies in our repeater cabinets in the future!). Meanwhile, because of the Holidays, the 220 machine will be down for a few more days. We cannot get immediate access to the building.

The point of this tiny blog is to suggest, don’t be afraid to use your screw drive to open the cabinet and peer inside. It is another way to learn. I have a table full of projects waiting surgery. But be Safe. Don’t stick your screwdriver into anything that is plugged in and powered up. This is the short cut to the big ham shack in the sky (pun intended).

Happy New Year everyone.

Rob K9RST