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DIY Plated Through Holes

Here's a method I have used to produce high quality plated through hole PCB's in Rogers RO4003C material, although it should work on any double sided board. Unlike some of the commercial and other methods, this requires just 1 tank of fluid and the materials can be bought for around £20. First, why? A little introductory background. I packed away my home circuit board etching equipment (or more likely threw it away!) many years ago. For the last decade or more, the easiest and cheapest way of getting good quality double sided (or even multi-layer) printed circuit boards in FR4 has been to simply produce the Gerber files on your favourite PCB design package and send them off to China.  You can get 5 boards made for less than £5, making them yourself is simply not worth it. I know, I know, giving money to China etc. The trouble is, FR4 is not really great for microwave. It has a high dielectric constant which can be quite variable depending on what particular board the supplier h...
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23cm Antenna progress

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 Some 3 years (god, is it that long?  it seems it is!) I started building some antennae for 23cm based on the "usual" DL6WU formulas, JVL calculations etc. Results were not good, the antennas would not resonate where they should, the pattern was sub optimal.   Some of the early failures, with success at the front.   Numerous attempts to fix them failed.  The problem was "boom correction" .. I was using 4mm rods in either 15mm or 5/8" (15.875mm) booms, with insulators. Various rules of thumb exist on how much extra length to add to compensate for what is "hidden" by the boom cross section. I specifically did NOT want to use elements directly embedded in the boom with an electrical connection to the boom itself, as while they may work initially, as corrosion between the elements and the boom sets in, performance is variable at best.    The realisation that "just adding 75% of the boom diameter" was not going to work came through building a pro...
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