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Old August 26th 10, 11:38 AM posted to rec.radio.amateur.antenna
Kba Kba is offline
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First recorded activity by RadioBanter: Aug 2007
Posts: 16
Default Direct connect 6 meter beam

On 16.06.2010 20:24, R.Scott wrote:
I see all kinds of crazy matching sections in posts about 6 meter
beams. How about direct connect. I have an A4S that has major issues
in the traps and I cant find the problem (IE I opened them and cant
find anything) SOOO I have a new A4S coming.

Has anyone taken an old 3 elem tribander and converted it to 6 meter
monobander using the direct connect.

Any Issues.

Would a 4 elem be better since its a long boom ?

I'm pretty sure I know the answers. Just want to confirm and see if
there is any reason not to direct connect rather than through a
hairpin or a gamma match.


Scotty W7PSK


Hi

Probably my comments are bit late... but OWA yagi's use direct feed to
driven element with a ferrite balun near the feedpoint.
OWA's give good impedance match in large bandwidth, this is based on
nearer driven element-first director spacing.
Otherwise gain, F/B etc. are very good.
I have constructed one 6m OWA yagi, with 20 ft boom as it was available,
using 7 elements in it, and finally with good match below
S 1.2 between 50...51 MHz.
Nothing critical in it, element dimensions were taken from NW3Z & WA3FET
article in OWA yagis, their 21MHz desing was re-scaled to 50MHz.
At least waterproofing is less critical in direct feed.

73's Kari