Topband: Newbie question
lars.harlin at one.se
lars.harlin at one.se
Mon Aug 23 06:33:17 PDT 2010
Snip:
> So I decided to start a serious investigation. Using an MFJ-259 tonight at
> the base of the antenna, I see 1 ohm of resistance and 400 ohms of
reactance
> at 1.8 MHz, for a length of 174 feet of wire. At 3.5 MHz, I see 25
ohms
> resistance and 85 ohms reactance.
>
>>From the readings, I have the following thoughts.
> * I would expect a higher resistance with the longer wire above ¼
wavelength on 160, say around 100 ohms, because an end-fed ½ wavelength
wire
> should be seeing 5000 ohms. Why the low resistance?
Mark,
Something must be seriously wrong there. Either the MFJ-259 or some
feedpoint error. I would suspect the tuner or its connections. 1 ohm is
impossible as resistive part of the impedance at that length of wire. Did
you measure with or without the tuner in line?
73 de Lars/SM3BDZ
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