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The book reference (link) stops before page 115. What is a HT detector? Google does not help me. May be this answer is not adequate related to your question: my DIY-SWR meter has a simple diode detector for forward/reverse and is based on a coupler (two toroid transformers) with factor -36 dB. Using 10 watts TX power (+40 dBm) this leads to +10 dBm (max ...


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Inductively tuned transmitting antennas were used in the military on HF man-pack radios. In the USA the Stoner company made a man-pack whip antenna in the 1970's for the US military that tuned 2 - 15 Mhz, if you search ebay and/or the net you might still be able to find examples described or offered for sale, but they weren't cheap. An Australian man-pack ...


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I can't dig up my source for this, but I'm pretty sure these spurs are just the result of rpitx using a fractional-N PLL (that isn't in any way optimized for phase noise) to generate a square wave. You get pulses of different (discrete) widths, which means you get spurs at predictable intervals. There isn't really anything you can do to make them go away, ...


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The "LoG" or "Loop on Ground" is a simple antenna to get you going. http://www.kk5jy.net/LoG/?fbclid=IwAR0dDk21M6XqZg7IwQ5NE7ggmS5Ux6Ivc_-_gtSZpE9Qbeu4EB9h5T4NGyU Like you, I have limited space in my yard, so the LoG works out nicely at a perimeter of 60 feet. You don't have to build the transformer yourself, as Black Cat Systems makes one for receiving ...


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The added capacitance of the RG58 stubs may also be an issue. I suggest using flat copper strip instead between the port connectors and the PCB. While you can probably get away with SO239's for just 2m, N connectors (or similar UHF connectors) are really mandatory here.


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