Unless you have no BC stations for 200 miles distant, making
measurements with an MFJ259 on 160m is going to give you unreliable
readings. The overload threshold on that band is extreemly low.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 18-Aug-18 6:10 PM, Gary Smith wrote:
Folks,
I'm starting to get ready for the upcoming
winter frolics on 160. The 160 antenna is
a sloper and I have somewhere around 50 or
so 130' radials pretty much buried under
6-7 years of leaves. When I went to the
remote coax switch & checked the readings
on the sloper with 10' of coax, I found
some readings with the old MFJ-259B that
concerns me.
I thought I'd cut the Sloper at 129' long
for best SWR at 1.825 but I'm now reading
the lowest SWR at 1.737 MHz and the
impedance read 85. Going back to the shack
I read the antenna (with 360' of 7/8 50
ohm commscope now in-between), and the
resistance drops to 55 but the SWR still
reads lowest around 1.737
It appears I need to shorten my antenna,
I'll have to work out the proper length
again but my concern is why at the feed
point would I see 85 for the resistance at
resonance.
Suggestions on what might I give a look to
when I go back out tomorrow?
Thanks & 73,
Gary
KA1J
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