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Old 26th Jun 2022, 5:38 pm   #1
G6Tanuki
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Join Date: Apr 2012
Location: Wiltshire, UK.
Posts: 14,010
Default "KW Match" SWR-meter.

Got this today at the Newbury rally; paid £3. It's been 'got-at' by a previous owner, who has replaced the original Belling-Lee type TV-aerial sockets with some strange SO239-types. The inside-the-box wiring being something that would have made Rowley Shears G8KW cry... [coax braid soldered directly to the socket-retaining-nuts using what I suspect was a pickaxe heated in a forge].

The 'sampling loop' is a length of old-style 75-Ohm semi-airspaced coax with a wire threaded down one of the longitudinal air-spaces; given that these days everything is 50-Ohm, I'm minded to replace this with a length of 50-Ohm coax, stripping off the outer sheath, bunching-up the braid to let me introduce a length of wire, then heatshrinking over the result.

BNC sockets to replace the nasty SO239-stuff too.

The diode used is also something I have never seen before... a curious white ceramic-type thing looking a bit like an old 1-Watt ceramic cased resistor. Knowing the issues with old diodes, I feel it should be replaced by something from my stock of nice OA47 gold-bonded ones.

Overall, I like its robust and uncompromising styling, and am sure it can be rendered fully-usable-for-the-21st-century without too much effort.
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