Ted’s essays

plumber’s 10-meter ham radio antenna

One avenue for local two-way radio communication is through the use of the 10-meter frequencies. I have not had a decent antenna for joining the conversation that is exercised most Wednesday evenings at 1915 hours on 28.350 MHz. For visualization purposes, CB radios are just slightly longer, around 11 meters – that is, very similar in antenna requirements – a fairly tall antenna like the spring-mounted whips you sometimes see on pickup trucks. I have had an antenna that transmits and receives ten meter okay, but it is in my little canyon (problem one) and is a horizontal while the rest of the local operators are using verticals (problem two). So I launched a project to design, build and […]

solar controller upgrade

The beast of a solar panel was too much for the economy controllers I tried. As I mentioned in my previous article about it, solar power upgrade, I put an antique ammeter on the incoming power that I could know how much was hitting the controller and a blade switch in the line so I could cut off the incoming juice when it became too much. This was not a system I could just leave on its own. If I was ever going to be able to ignore it, and if I wanted to absorb maximum power from the sun on this system I needed to upgrade the controller. When my refund from the smoked controller arrived I did […]

solar power upgrade

When I set up my ham radio shack six years ago, I chose to go solar-powered 12-volt because amateur radio needs to work regardless of the grid up or grid down situation. Last year I upgraded to second and third deep-cycle lead-acid batteries. I added other uses to the system and last winter was frequently running low on stored energy. So I upgraded the panel and controller to modern, more powerful ones. The new panel overwhelmed the new controller. It should not have according to the specs on both, but there it was. Controller said, “Too much juice”. Readily admitting to my ignorance, I contacted a company with a long history of servicing the off-grid community and ordered a […]


The Amateur Radio Relay League (ARRL) began as volunteer radio hobbyists relayed welness checks from war zones back to families stateside, quickly morphing into passing information traffic back and forth using the budding radio technology. Amateur radio has been innovating ever since. Among the tools developed to insure accurate message handling is the RADIOGRAM. A form that insures the intended message reaches the target intact. Here is a .pdf of that form so you can see it full sized and print your own. RADIOGRAM There are a number of very good handling instructions on the world wide web. Shop around for your favorite: https://www.qsl.net/mingoares/forms/instructions.html http://www.ws1sm.com/Message-Handling.html https://emcommeast2011.s3.amazonaws.com/RadioGram.pdf I made a copy that is as brief as I could while maintaining the […]

ICOM IC-F3161DS handheld radio SALE

My wife has transitioned from carrying one high-end VHF (Ham 2-meter) ICOM radio as well as one high-end UHF (GMRS+FRS) Connect Systems radio to a single dual-band Chinese TYT radio. That means her very well maintained Ham radio is available on a first come, first served basis. The CS radio is not worth enough to sell. I will just add it to the pool of GMRS loaner radios. Her ICOM IC-F3161DS HAM radio comes with a charger and two batteries that are in excellent condition. While she carried this radio in her travel bag, it has very little use and no scars or marking anywhere. I do not know where the cover for the speaker-mike connection is, but fifteen […]

two-way radios

can be indispensable in emergencies and other times normal communications tools are not working. For my current amateur radio Technician Class students, I just bought 7 of the make/model I feel gives the best cost/benefit for ham radio operators. The TYT MD-UV390 operates on both the ultra-high-frequencies (UHF) of the FCC’s family radio service (FRS) and general mobile radio service (GMRS), it also transmits and receives on the very high frequencies (VHF) commonly used by hams, public and private agencies for regional communications. Their MD-UV380 is the lower cost version of the same radio without the water-proofing. TYT, also known as Tyterra builds well-reviewed radios in relatively affordable price ranges. The transmitters, receivers, speakers, microphones, displays, controls and antennas all […]

2-way radio repeaters

I created a presentation for our local ham radio club to explain the environment our repeater engineer was dealing with. The problem many great sites have is that their prominence attracts multiple transmitters with each addition making it harder for the repeater to pick up the signals we want out of the electromagnetic flood. Thus the situation I describe with this Downing Mountain repeater is common to many. I called this “Tracking A Transmission”. We follow a signal from the operator’s mouth through his radio and up to the repeater overlooking Hamilton Montana. Once the repeater gets the information, it transmits it out from a large antenna with 50 watts of power pushing it as much as 50 miles away. […]

electricity, components & circuits

Chapter 3 in the Amateur Radio Relay League (ARRL) Ham Radio License Manual is the most challenging to most students. Remember that out of the 35 questions on your written exam, 26 correct answers is a passing score. You can afford to miss nine, or one out of every four and still earn your Technician’s License. You could miss, or even skip over every component and circuit question without failing your exam. Do not get all balled-up in this one chapter. On the other hand, it is cool, and even useful to understand a bit of this stuff. So let’s try to GET IT, without stress or strain. You likely already found my favorite online exam preparation tool HamStudy.org I […]

wave behavior

Whether it is a stone tossed into a glassy-smooth pond, sound waves coming out of a trombone or electro-magnetic waves enabling radios to communicate, the wave behaviors are direct relatives to the physicist. One such person built a model to demonstrate wave behavior then his employer, Bell Labs, produced a movie of it. I almost called it a video, but those were not yet invented in 1959 when this was produced. Last year I pounded enough correct answers into my head that I passed my Amateur Extra exam. My motivation was that I really wanted to UNDERSTAND radio much better. I did not clear that hurdle on pure expanded knowledge of radio, but I found several tools that helped. […]

Darby Dog Derby 2020

I led a team of ham radio operators who provided two-way radio communications throughout the two day event. It really was fun for all… the mushers, the comms guys and the visitors who came to watch the show. I mostly stay secluded in my comms truck shell, “The Beast” where my mobile radio has the speaker volume so I can hear radio traffic over the dog noise. I did step out to take a few photos and three short video clips that I share here. Darby Dog Derby Skijor 11 start from Ted Dunlap on Vimeo. Darby Dog Derby 8 Dog hookup part 1 from Ted Dunlap on Vimeo. Darby Dog Derby 8 Dog hookup part 2 from Ted Dunlap […]

comms plans for Darby Dog Derby

The 2020 Bitterroot dogsled race weekend is coming up. I have the two-way-radio support plan mapped out, radios programmed, testing complete, batteries all charged up … I think we are as ready as we can get. For more details about the weekend, the participants and the races, go to The Bitterroot Mushers website. Each year we learn more, adding refinements to patch holes as we find them. Ideally we have 8 checkpoints with a checkpoint worker and a radio operator at each. That’s a bit dreamy as the last couple years we are lucky to have one person serving both roles at each. Bitterroot Emergency Amateur Radio Services (BEARS), the comms team, recently changed affiliation to Corvallis American Legion […]

final day of registration for ham class is Friday

This a repeat of my previous announcement. There is one more day of online registration for Darby Adult Ed classes. We stand ONE STUDENT SHORT of having enough to make it happen. I am bringing another amateur radio operator licensing class to Darby, Montana via the Darby Adult Education program in its Spring 2020 schedule. I have not keept track, but think I have personally assisted 40 or 50 people to earning their FCC licenses through my study groups in the Darby library. The snide saying goes, “Those who CAN, DO. Those who cannot, TEACH”. I’m okay wearing that. Good instructors are as rare as good anything else. I did not choose this calling, blessing or curse. It chose me. […]