MTR-3b to Return!

This is from the LNR precision Web site: Update: 2/16/23: MTR4 V2.3 is not available for purchase now but we will be offering these again in the Spring of 2024. We don’t have an exact date yet but the target is by the end of March. This will be the only and last offering of the MTR4b V2.3 radios as we are shifting focus on a redesigned and re-engineered version of the popular MTR3B! It is our hope to have these out in Fall of 2024 if possible, but no guarantees. I’ve been trying to buy a MTR-3B LCD for years

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SW-3B_W9TH.com

SW-3B Display Problem – Fixed!

The SW-3b is my favoite POTA rig. About June of 2023, the radio developed a problem with the LCD display. At first, the display would have random characters on one line. This was intermittent. As the year progressed, with each POTA activation or use, the display got progressively worse. The entire display would be garbled after a few minutes of use. The last time I tried to use it for a POTA activation in October 2023, the display was completely blank when the radio was turned on. I spoke with Dale at Venus about the problem. He suggested re-soldering the

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W9TH QRP Antenna Trap

QRP Antenna Traps

These traps were specifically desiged to use mini-ductor type coils. I had mini-ductor coil stock on hand, so I wanted a design that would be produce a higher Q trap than ones made with torroids. However, the design can easily be used with torroids. There is a mounting hole for use with a nylon screw to hold the torroid in place. Also, there are places to add multiple capacitors in parallel in case you needed a custom capacitance to achieve resonance for a particular band. The trap PCB can easily fit into a small pill bottle for weatherproofing. For temporary

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QRP Guys End Fed Half Wave Antenna – Part 3

I didn’t have time to test the antenna before our cabin trip, so I took some measurements on-site. The antenna was strung between the upper deck of the cabin and a nearby tree. The wire I used was 63 feet long, I intended to cut it to length when the antenna was put up. What actually happened was I passed the end of the wire through a plastic dog bone insulator and wrapped it back on itself about a foot, and called it good. The SWR turned out to be so close to perfect, I didn’t make any adjustments. Here

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