Hi thanks Andy and Dick. I couldn't believe that coax would be a dummy load
at 136k either but although there is a formula for the Q of the 'inductance'
formed by the shorted line I could not think of a way of deriving one of the
terms....actually what current IS flowing in the conductors. Andy's figures
make a lot of sense and it just goes to confirm the old adage " you don't
get owt fer nowt". OK I must plead stubby geriatric fingers for the extra
order, I was probably mentally slowing light down to my speed! Certainly the
reactance changes very rapidly with frequency, and I suspect this was why
only a part of the loading uses the shorted stub in the Wireless World
article ( there being lumped inductors shown as well).
Ah well I can put my old UR67 to better uses and the neighbours can sleep
peacefully as I don't need install an old 'grid' pylon to support the
loading inductor.
Some idiot has got to keep asking the silly questions!!
73 de Alan G3NYK
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