Topband: Newbie question

lars.harlin at lars.harlin at
Mon Aug 23 06:33:17 PDT 2010

> 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
> at 1.8 MHz, for a length of 174 feet of wire.   At 3.5 MHz, I see 25
> 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
> should be seeing 5000 ohms.  Why the low resistance?

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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