[Elecraft] OT antenna question

[Michael Blake]

While off topic this antenna supports an all Elecraft station.

I have very limited antenna space and my 80M/20M shortened dipole consists of 17’ center sections connected to approximately 44uH, 2.5” OD inductors with 10’ end wire sections past the inductors and terminated in end insulators.

The center sections of the dipole are tuned for resonance at about 14.15 MHz and the end sections, past the loading inductors on each dipole leg, are tuned for resonance a 3.7 MHz.  The resonance dips at both frequencies are quite sharp and the SWR on both bands is less than 1.5 to 1.

The question that I can not get my head around is this.  On 20M the two inductors are acting as chokes and not traps but I have no idea what the losses might be with these chokes acting as end insulators rather than a trap or actual insulator.

In actual operation the antenna works quite well on both bands but I would like to get an idea on how efficient these inductors are when used as chokes (4,000 ohms) on 20M.

Very 73 - Mike - K9JRI

K3s - P3 - KPA500
KX3 - KPA500








Michael Blake
k9jri at mac.com <mailto:k9jri at icloud.com>