Search String: Display: Description: Sort:

Results:

References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*Topband\:\s+Inverted\s+L\s+SWR\s+Jumps\s+\?\?\?\s*$/: 20 ]

Total 20 documents matching your query.

1. Topband: Inverted L SWR Jumps ??? (score: 1)
Author: Ashton Lee <Ashton.R.Lee@hotmail.com>
Date: Tue, 27 Nov 2012 22:49:18 -0700
So I am trying to get set up better on 160 meters. I now have two antennas up (pretty well separated). One is an Alpha Delta DX A sloper hung in a tree with a grounding wire led to a ground rod and s
/archives//html/Topband/2012-11/msg00417.html (8,176 bytes)

2. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: W2PM <w2pm@aol.com>
Date: Wed, 28 Nov 2012 01:35:28 -0500
I think you have a bad connector somewhere - I will guess there is a pl259 going into that choke balun - you may have a poorly made connection to the coax which shorts out at high power. I don't thin
/archives//html/Topband/2012-11/msg00418.html (9,776 bytes)

3. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "Tim Duffy K3LR" <k3lr@k3lr.com>
Date: Wed, 28 Nov 2012 00:45:08 -0600
Hello Ashton, I am curious what "pretty well separated" is at your QTH? Two 160 meter antennas separated by 240 feet is the same as having two 2 meter antennas 38 inches apart. There is significant c
/archives//html/Topband/2012-11/msg00419.html (9,402 bytes)

4. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: Jeff Woods <jmwooods@yahoo.com>
Date: Wed, 28 Nov 2012 07:53:09 -0800 (PST)
"The inverted L loads just fine to about 700 watts and then causes the Alpha amp to fault out. I think I am getting a sudden change in antenna impedance. The antenna is fed through a 5 KW rated choke
/archives//html/Topband/2012-11/msg00428.html (7,870 bytes)

5. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 28 Nov 2012 11:14:49 -0500
The sloper loads fine all the way up to 1500 watts. The inverted L loads just fine to about 700 watts and then causes the Alpha amp to fault out. I think I am getting a sudden change in antenna imped
/archives//html/Topband/2012-11/msg00431.html (9,902 bytes)

6. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: HAROLD SMITH JR <w0rihps@sbcglobal.net>
Date: Wed, 28 Nov 2012 08:51:46 -0800 (PST)
The sloper loads fine all the way up to 1500 watts. The inverted L loads just fine to about 700 watts and then causes the Alpha amp to fault out. I think I am getting a sudden change in antenna imped
/archives//html/Topband/2012-11/msg00432.html (8,253 bytes)

7. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "Jack Henry, OA4TT" <n6xq@yahoo.com>
Date: Wed, 28 Nov 2012 09:03:43 -0800 (PST)
Hi Ashton, I had some arcing into a coral tree at the 20 ft level.  The vertical part of the inverted L was  supported by a 40 ft bamboo pole that was nested close to the coral tree.  The wire was #1
/archives//html/Topband/2012-11/msg00433.html (10,833 bytes)

8. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "Charles W. Shaw" <charleswshaw@gmail.com>
Date: Wed, 28 Nov 2012 17:19:59 +0000
Ash, You said, "I've replaced every component in the system except for the antenna wire." Also, if the antenna wire is (or is partly) an insulated variety, it is possible to have an open fault inside
/archives//html/Topband/2012-11/msg00435.html (7,980 bytes)

9. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 28 Nov 2012 12:30:16 -0500
Remove the balun. It's not doing anything for your and is a potential source of loss and problems. Coaxial cable is unbalanced, as is a ground-fed inverted L. No need for a balun. >>> Unfortunately,
/archives//html/Topband/2012-11/msg00436.html (10,247 bytes)

10. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: Ashton Lee <Ashton.R.Lee@hotmail.com>
Date: Wed, 28 Nov 2012 11:14:26 -0700
Ok, everyone thanks for all the help. I rebuilt the antenna from new wire, built a two insulator termination at the end of the horizontal section where the high voltage is, I rehung the new antenna s
/archives//html/Topband/2012-11/msg00438.html (11,392 bytes)

11. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "Bob Eldridge" <eldridge@direct.ca>
Date: Wed, 28 Nov 2012 09:58:57 -0800
Tom: MOST antennas are in a "neither" world of being neither perfectly balanced nor perfectly unbalanced. How about an inverted L longer than 1/4 wave but optimized with series capacitor? Any closer
/archives//html/Topband/2012-11/msg00439.html (8,816 bytes)

12. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: Jim Brown <jim@audiosystemsgroup.com>
Date: Wed, 28 Nov 2012 10:40:02 -0800
YES! and this coupling could be problem for your set up. But it can also be a good thing if you know what you have and how to take advantage of it. I have three resonant verticals for 160M, as well a
/archives//html/Topband/2012-11/msg00441.html (9,900 bytes)

13. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: Jim Brown <jim@audiosystemsgroup.com>
Date: Wed, 28 Nov 2012 10:56:56 -0800
One thing I observed here several years ago with a dipole with an end touching tree branches is arcing to the branch, accompanied by scorching of the wire insulation (white THHN). Also, a common mode
/archives//html/Topband/2012-11/msg00442.html (10,247 bytes)

14. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: DAVID CUTHBERT <telegrapher9@gmail.com>
Date: Wed, 28 Nov 2012 12:56:05 -0700
W8JI solved another problem and saved someone much time and frustration. I'd like to thank Tom for the great help and knowledge he has imparted in me and many, many others over the years. In my exper
/archives//html/Topband/2012-11/msg00443.html (10,410 bytes)

15. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: Mike Waters <mikewate@gmail.com>
Date: Wed, 28 Nov 2012 14:03:24 -0600
I second that! Being acquainted with Tom over the years and reading his informative posts has wonderfully enriched my enjoyment of radio. :-) 73, Mike www.w0btu.com __________________________________
/archives//html/Topband/2012-11/msg00444.html (9,870 bytes)

16. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: Guy Olinger K2AV <olinger@bellsouth.net>
Date: Wed, 28 Nov 2012 15:12:58 -0500
The change in an overheating core has a swing to it and you can watch the SWR change, in a continuous fashion, while you are transmitting, while arcs exhibit sudden change. What you call "imbalance"
/archives//html/Topband/2012-11/msg00445.html (10,937 bytes)

17. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "Joe Subich, W4TV" <lists@subich.com>
Date: Wed, 28 Nov 2012 15:23:55 -0500
Simply because the ratio of voltage varies along the feedline if the SWR is anything other than a perfect 1:1. The feedline length and SWR for your inverted L was probably just right to put a high vo
/archives//html/Topband/2012-11/msg00446.html (9,035 bytes)

18. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: Jeff Woods <jmwooods@yahoo.com>
Date: Wed, 28 Nov 2012 13:11:21 -0800 (PST)
That's true; I did assume a reasonably good ground plane, to the extent that the unbalanced assumption would be accurate.  Still - it's a component that can be removed - at least temporarily - to see
/archives//html/Topband/2012-11/msg00447.html (12,039 bytes)

19. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 28 Nov 2012 21:03:33 -0500
Tom: MOST antennas are in a "neither" world of being neither perfectly balanced nor perfectly unbalanced. How about an inverted L longer than 1/4 wave but optimized with series capacitor? Any closer
/archives//html/Topband/2012-11/msg00449.html (11,678 bytes)

20. Re: Topband: Inverted L SWR Jumps ??? (score: 1)
Author: "ZR" <zr@jeremy.mv.com>
Date: Wed, 28 Nov 2012 10:01:29 -0500
Ive often wondered about actual coupling Tim as compared to modeling. For decades Ive had an inverted vee midway between a pair of full size sloping verticals all on the same tower. The vee feedpoint
/archives//html/Topband/2012-11/msg00450.html (12,978 bytes)

Current List: 1 - 20
Page: [1]
This search system is powered by Namazu