Could you explain all this to those of us who are electronically
challenged.? In other words "HuH'?
>Graham E Laucht wrote:
>>
>> In message <339DBB9A.77B5@carib-link.net>, Ember <ember@carib-link.net>
>> writes
>> >I wonder whether anyone has considered a dipole made by sticking the
>> >copper tape to the inside of the fuselage skin
>>
>> I looked at the same on Duncan's "boat" and reckoned a tape vertical up
>> behind the luggage bay bulkhead might also work though it would have a
>> rather disturbed radiation pattern especially in the forward direction.
>
> And which is why I didn't suggest this location !
>
>> Given that we need to talk to people in front of us more often than
>> those we are leaving
>
> Well, I'm not too sure about that ! I seem to spend most of my radio
>time talking to the tower, which is only in front of me when I am on the
>last leg !
>
>>
>> NB, Centre fed half wave antenna have a terminal impedance of 75 not
>> 50ohms or 73+j42ohm to be pedanticaly exact and need a balanced feeder.
>
> Precisely - which is why the impedance of a centre fed dipole is taken
>as 72 ohms for practical purposes. BUT I suggested using the curvature
>of the fuselage plus any necessary internal angle to produce a dipole
>with the arms not in line - ie. a shallow "V". As in the case of the
>usual quarter wave groundplane this should produce a 50 ohm match.
>Yes, in theory a balanced feeder is needed and if you want to be fussy
>when using coax then a balun is required at the antenna feed point - but
>in practice this doesn't seem to make any discernable difference.
>
>
> Martin
>
>
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