Energy Choices for the Radio Amateur

Justin Patrick Moore's picture

One of the things I am excited about in Amateur Radio, is that through learning the basics of electricity necessary to get my ticket, I am also preparing myself to learn about energy to a greater degree as well. A new book published by the ARRL is a case a in point.

Here is a brief summary:

"Energy Choices for the Radio Amateur
Your Power Sources in the 21st Century

Revolutionary changes are taking place in the way we produce and consume power for our homes, transportation, and the technology that we use every day. This book explores the ongoing changes in the world of power and energy, and takes a careful look at the choices we can make. Home solar or utility power? Oil/gas heat or electric heat pump? Gas car or hybrid/EV?

Energy Choices for the Radio Amateur details the author’s experiences with new sources of energy. It is intended to help other radio amateurs and DIY hobbyists prepare for the inevitable major energy decisions they will face — choices that can contribute to a reduction in fossil fuel use and save money in the long run. The concepts presented in this book not only satisfy everyday power requirements, but also can help prepare for emergency and backup power at home and in the field."

So by learning about electricity and power in the circle of communications & transportation I can also develop some skills in the seventh circle of energy and power. The two overlap, just as all these circles do.

I'm also the librarian for the radio club I am a member of -something I hope to write a bit about in the future (how to run a club library). I think I will get this book for the clubs library that way a number of people might benefit from what it has to teach.

lathechuck's picture

I salvaged an obsolete solar panel, 200W, from a Solar City salesman, and wired it up to a small charge controller (by Grape Solar, a GS-PWM-40BT), and a small (7 Ah) sealed lead-acid battery. This worked well enough, on a sunny day, to run a 100W HF transceiver (Kenwood TS-130SE) in SSB mode to make a few contacts. One of my neighbors, a construction contractor, accidentally cut into one of his long, fat (10AWG) extension cords, and let me salvage it (rather than risk a spliced wire on a job). That gives me 50' or so of freedom in locating the panel in the sun, and the radio in the shade, where they each do their best work. The current from the panel to the battery is lower than the current from the battery to the radio, so the panel is all alone out on the end of the cable. However, nothing in the charge controller documentation specified a minimum capacity rating on the battery. Even my efforts to contact the manufacturer obtained only vague suggestions.

I can assure you, though, that the limiting case of "no battery" was immediately fatal to the charge controller! My plan was to swap batteries, but I neglected to isolate the charge controller from the solar panel first. My NEW charge controller is supposed to handle two batteries, so I can switch the load from one to the other without disconnecting the batteries from the charge controller. The weather may be warm enough this weekend to get it all outside for a test.

lathechuck's picture

Anyone looking for a small, efficient, general-coverage receiver for "situation awareness" (as well as entertainment) should check out the CountyComm GP-5/SSB. As of March, 2019, it's on sale for $72. I've had one for a few years, and it's my constant companion while walking to and from my carpool meeting point. Since it covers AM and FM broadcast bands, I can get local traffic and weather reports, and because it has genuine LSB/USB reception from 1.711 to 29.999 MHz, I can listen to the SW broadcasts, hams, CW practice sessions on W1AW, and the Time Being from Colorado, on 2.5, 5, 10, 15, and 20 MHz, (propagation permitting). It runs on three AA batteries, or external DC from a mini-USB port, and includes battery state-of-charge monitoring (gas gauge) and built-in battery charging control. It accepts an external coaxial antenna connector (1/8" plug), so I've put my 80m dipole on it with good results. Of course, it doesn't do many of the things that my desktop HF rigs do, but then, they don't ride in my coat pocket every day.

Regarding energy, there are very small photovoltaic systems that put out DC power on a USB port. Think of your basic "solar power bank phone charger". I've used one that's about 2.5x6" to keep my GP-5/SSB charged up.

(I have no financial interest in the company. I'm just really impressed with this product.)

lathechuck's picture

I saw a news segment this week that the standard-size solar panel for residential installations now puts out 400W peak. Five years ago, the ones I bought were just 250W peak. (And that's why I was able to get a 200W solar panel just for asking. The Solar City sales guy who had it said that he was thinking of using it as a coffee table!)

Justin Patrick Moore's picture

Coffee table? For real?
Thanks for your comments here on this thread. I hope we can try to meet up on 40 meters sometime.

Right now I'm going through the book "Basic Electricity: a text-lab manual" by Paul Zbar with two of my friends in a little study club. We are going to "build" the circuits in the free software program lt-spice. Hopefully this practice will help me get a good 'grounding' in electricity fundamentals.

I might have to pick up that county comms general coverage receiver after all. Very cool about your solar cell for your rig.

Blueberry's picture

Please be safe 500 millamps can KILL!!! If you have questions please ask.

lathechuck's picture

Blueberry - Justin mentioned "building" circuits using LTSpice, which means that he's not actually building them at all, but simulating them with a very powerful bit of software. The circuit diagram can be drawn on the screen, component values defined, and then its behavior can be plotted under a variety of stimuli. (I started doing such simulations decades ago.) On the plus side, it's totally safe, for both the experimenter and the components, it's quick (to change a component value, just type in the new number), and it's very inexpensive (assuming that you have any reasonable sort of computer, the program costs nothing, and neither do the simulated components). On the minus side, none of the circuits have any connection to the Real World: a simulated battery-charger won't charge a battery; a simulated radio won't receive a station. The real beauty of the practice, though, is "negotiating" with the Real World to predict the performance of the project you want to build, with the components that you happen to have on hand. In a world of salvaging components from old devices, we might not have a lot of choices for obtaining the ideal components. Simulations can help find a feasible compromise.

Blueberry's picture

If you look at a 1930s radio the resistors for the most part 20% +/- Ecaps -50+20 paper caps are just that AL foil and wax paper with a little candle wax on the ends. Circuit layout is very important. 10 years down the road and what you will be making is shall we say primitive. For fun try winding a Osc coil. Take a piece of galena an make a simple AM radio. Lots of stuff today has a very short mean time to failure.