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unless im missing something we have covered this before several times,

1/2wave multiples of mast or coax connected to ground reflect the low end impedance giving you a low common mode impedance= high common mode current magnitude, this is w8ji's worst case scenario,

odd 1/4wave multiples of grounded mast/coax invert the low end impedance giving you a high common mode impedance= low common mode current magnitude, best case scenario,

if the mast/coax is not connected to ground the impedance and current magnitude are inverted,

1/2wave multiples reflect the high ungrounded end impedance giving you a high common mode impedance= low common mode current, best case scenario,

odd 1/4wave multiples invert the high ungrounded end impedance giving you a low common mode impedance= high common mode current, worst case scenario.

<blockquote data-quote="bob85" data-source="post: 419730" data-attributes="member: 18">unless im missing something we have covered this before several times,&nbsp;1/2wave multiples of mast or coax connected to ground reflect the low&nbsp; end impedance giving you a low common mode impedance= high common mode&nbsp; current magnitude, this is w8ji&#039;s worst case scenario,&nbsp;odd 1/4wave multiples of grounded mast/coax invert the low end impedance&nbsp; giving you a high common mode impedance= low common mode current&nbsp; magnitude, best case scenario,&nbsp;if the mast/coax is not connected to ground the impedance and current magnitude are inverted,&nbsp;1/2wave multiples reflect the high ungrounded end impedance giving you a high common mode impedance= low common mode current, best case scenario,&nbsp;odd 1/4wave multiples invert the high ungrounded end impedance giving you a low common mode impedance= high common mode current, worst case scenario.</blockquote>

[QUOTE="bob85, post: 419730, member: 18"] [I]unless im missing something we have covered this before several times, 1/2wave multiples of mast or coax connected to ground reflect the low end impedance giving you a low common mode impedance= high common mode current magnitude, this is w8ji's worst case scenario, odd 1/4wave multiples of grounded mast/coax invert the low end impedance giving you a high common mode impedance= low common mode current magnitude, best case scenario, if the mast/coax is not connected to ground the impedance and current magnitude are inverted, 1/2wave multiples reflect the high ungrounded end impedance giving you a high common mode impedance= low common mode current, best case scenario, odd 1/4wave multiples invert the high ungrounded end impedance giving you a low common mode impedance= high common mode current, worst case scenario. [/I] [/QUOTE]

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