TAK-TENNA
"patrick.obrien47" wrote in message
...
HI
Has anyone bought this small TAK-tenna HF Aerial
? or know anyone that has?
Just wonder how they got on with it.?
Patrick GW1SXN
Just for curiosity I once ran a NEC simulation of the "TAK-tenna" on 7 MHz
at 30 ft
above an average ground. The input impedance at resonance is 3.4 ohms, and
radiation efficiency just under 9%. Using 50 ft of RG-213 the input
impedance
is 5.4 + j 12.4 ohms, and line loss 1.72 dB. Maximum gain, at a 30 degree
take-off
angle, shows -7.7 dbi. Nulls off each end are -14 dbi.
With the above results an input power of 100 W radiates 6 W. I believe they
claim
a low input VSWR. Have no idea how they achieve it without a matching
network.
73,
Frank
(VE6CB)
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