practical yagi question
On 16 Feb, 22:07, "Jimmie D" wrote:
wrote in message
well, I made two quagi one year, they worked well. The problem is that
you don't easily find good design procedures for quagi (neither for
quads).
Thats probably because both antennas can be made to incredibly slack
tolerances and still work quite well. I hacked together a Quagi for my cell
phone a few years ago while camping that worked beter than my factory made
yagi.
hmmm that's not entirely true in my experience. One year I made a 4
elements quad for the 50 MHz band, simulated with nec using bare wires
and no boom, then built with metallic boom (and insulated wire spokes
of course) and with insulated wires, same diameter as in the
simulation. The result was so badly detuned that it actually had more
gain in the back direction than the forward one, SWR was like 3:1.
Probably the effect was due to insulated wire, but never investigated
further, I just dismantled it and built an 8 element yagi instead.
So far though nobody answered my original question as wether unaligned
driven element on yagis will have or not effects on tuning/
performance.
Thanks
Francesco IZ8DWF
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