1.4:1 It's A Miracle!

[n3lrx]

 Well, I was going to get on here and say: "I've got my SWR down to 1.4:1 at 100 W carrier without a tuna!" But I must have bumped something because it's sky high again, 5:1.

  The only thing special inline is an ugly balun and I added a few coat hangers. I had to lengthen the antennas about 4 inches to get them resonant on 3885. 3880, and 3875 were also within 2:1 range with a tuna.

 I don't know what I did. It must have been so fragile that even bumping it threw it off again. I did go outside on the balcony to see who was setting off fireworks. That's all I can think of that might have done something.

 The good news is the choke is doing it's job because the transmitter is not hot when I key up, and there is no buzzing in the computer speakers. So the common mode is gone.
 
 I bought a SARK100 antenna analyzer on ebay for $90 and it paid for itself today. It took all day but I managed to get the SWR down so in spite of tonights little set back, I am very happy, a little more work tomorrow and hopefully I'll have something a little more stable.

 I still have to get longer coax so I can route it differently and avoid kicking it if I walk out the door. Right now it's only about 20ft of coax. I would like more so I can at least close the door most of the way.

 Hope is in the air!

[Opcom]

A bad or loose center contact in an SO-239 caused me many troubles intermittently.

[W3RSW]

Same here in an ell. That center pin is actually screwed in and actually has a little hex at its base to do it!

Um, also an instantaneous 1.4:1 SWR could be caused by a short that just as suddenly went away. In your case, Hope not.

[steve_qix]

I'm assuming you're using coax feed.  1.4:1 is not unusual.  I get 1.2:1 and even 1:1 (depending on frequency) with coax feed most of the time, unless I go very far from the center frequency of the antenna.  For instance, at 3885, it's about 1.3:1.  On 3820 it's close to 1:1.  On 3700 it's back up to around 1.5:1.  So, it is definitely possible to achieve a good match and over a fairly wide frequency range with coax feed.  Multi-band operating is achieved by using the "fan" approach - more than one dipole on the same feedline.

Oh, I decouple the coax from the antenna by running the coax through 20 type 43 ferrite cores at the feedpoint.  Works well !  Do the same thing at Rattlesnake Island.

Regards,  Steve

[n3lrx]

Here's my antenna. (I take the lanterns down when I try to operate or tune the antenna.)

[W3RSW]

So Randy, what did you find?
Fixed and steady?

[n3lrx]

 Not yet. I haven't had the chance to fool with it again. I'll fiddle with it this weekend and see what I can get out of it. If I got a good reading off of it before I'm sure I can do it again. I'll even settle for a tuner 2:1. The most I can tune it down to now is 5:1. I'd just love to know what changed.

 Maybe it's all in my head, but I noticed the noise went down since I installed the choke. I like that. It's still about 3 s-units but that's better than 5! The tone of the noise has also changed. It's no longer electrical sounding (buzzing) it's more of an atmospheric sound (hissing).

[Opcom]

Hopefully the 'gain' remained when the noise went but I'd trade 10dB for getting rid of the line noise type buzz any day.

[n3lrx]

Heck, I'm just glad I don't burn my fingers when I touch the transmitter, or anything else metal attached to it. I got it down to about 3:1 can do more work this weekend.