[TowerTalk] Stub Matching a Half Wave Vertical

[Simon Martin]

I need some advise as to the dimensions for coax stub matching a 17 metre
(18.150 MHz) end fed vertical half wave that I hope to use as a portable
antenna.

It is tapered aluminium from 1inch to 0.625 inch in four sections - the
feedline and (shorted) stub section will all be regular RG58 50 ohms coax.
Trying to calculate the dimensions of the stub/line section via the Smith
chart leaves me rather baffled and in need of a cold beer !

Any help would be greatly appreciated.

Regards,
Simon - M0GOT