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KST2YOU - An alternative interface to KST

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  If any of you use KST and want to try a slightly (hopefully) more friendly user interface, I have published one here: https://kst2you.bss.design/   Amongst the design requirements were that it should run from a phone or tablet, as I really can't be doing with dragging a laptop around for portable trips for microwave stuff. It all runs in a web browser, and obviously on any desktop with a web browser.   If you already have an account on KST, you can just log straight in, you usual username and password will work.   The message interface is familiar to you if you have used KST, however I've tried to fix a few of the oddities of the traditional KST interface. One of the problems in a busy contest day is if you are trying to organize contacts say in the north of England and have range of at most 300km, you probably don't need to see messages from stations chatting in Italy.  The "filter by distance" option allows you to ignore chat from stations beyond a certain di
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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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13cm LNA design.

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 When I did my electronics degree, all those years ago, I wasn't really paying much attention to RF design, so I've had to learn a lot of this from scratch, as I failed to pay sufficient attention way back then. I thought I would have a go at building an LNA for the 13cm band as I had a transverter that didn't really seem to perform as well as I wanted. 13cm/2320MHz is high enough to be interesting for design, yet should still be accessible with FR4 substrate for the circuit boards. Certainly, for higher bands, PTFE substrates are becoming more appropriate, but 13cm should still allow FR4, and as my initial attempts are likely to be needing fine tuning, FR4 is a much more "experimenter friendly" choice. There are essentially 3 parts to the design and evaluation process:            The basic schematic with the bias circuitry.          The RF design          Performance evaluation. The basic schematic and bias  scheme were as a result of my choice of active device f
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