Topband: Still in search of resonance

[Tom W8JI]

Hi Carl,

It sounds like you are trying to find 50 ohms on the tower without any 
series capacitor by looking at R and X. I would not try to do that. The 
reactance puts you out of range on the MFJ bridge.  You are down to a few 
bits difference between data points the PIC needs in the MFJ.

Look at this below. You said:

<<<<seen at the other levels too as long as I brought the R down with a 
variable cap.  Yesterday, with the gamma arm at the 46' level (and 240 ohms 
on the MFJ) I was able to put the big variable inline to bring the reading 
to 24 ohms with a TRUE X=0.  With a 22 ohm to 50 ohm UNUN, I saw 1.3:1 Vswr 
on the output of the UNUN.  I worked a W2 in NJ and a W4 in Florida with 
just the 1000D.  BUT...again...I'm bringing the R down with the 
capacitor...not finding 50 ohms anywhere on the tower>>>>

Stop trying to find 50 ohms without the capacitor!!!!!

Right now at 46 ft you were at 24 ohms with the capacitor. That should tell 
you and everyone on this reflector :-)   that you are tapped too low now!

Let's look at this in simple terms. Here is what you said:

<<<<<When I had the gamma arm mounted at the 90' level. I was able to put my 
baby variable 160pf inline to bring the 425 ohm impedance down to about 60 
ohms and the antenna heard very well; especially on the 1700 KHz broadcast 
band, with a 2.4:1 Vswr.  Similar results could be seen at the other levels 
too as long as I brought the R down with a variable cap. >>>>>

That is NORMAL. You will always need the capacitor. Always. The only way to 
eliminate the capacitor is to saw your Yagi antenna off the tower so the 
tower moves above 2 MHz. Then you will probably find a 50j0 tap without any 
capacitor.

You also might use a large skirt, but why??????

Just use a capacitor!!!

If you are trying to eliminate the capacitor, you will have a lot of work to 
do.

73 Tom