I have a Tec Tec Auto Coupler that is turned off and a Ten Tec Hercules II at full power. The SWR bridges in side the equipment reads well over SWR over 3:1 on certain bands while my BIRD Watt meter
would an unun help to keep common mode current from flowing? jack ak7o I have a Tec Tec Auto Coupler that is turned off and a Ten Tec Hercules II at full power. The SWR bridges in side the equipment
By definition, no. You almost certainly are enjoying an unbalanced current on your feed line, likely a current on the outside of the coax shield causing an erroneous reading. You'll need to alleviate
Sounds like RF current on the shield when on the antenna and not on the dummy load. I suggest a 1:1 UNUN balun between the amp and the antenna. I've had good success with a product from The Wireman b
Maybe "unun" and "balun" don't really apply here. Walt Maxwell, W2DU, and Lew McCoy, W1ICP, were famously at odds about whether the W2DU "balun" was really a balun or something else. Walt said yes, L
Semantics.......be it a UNbalanced to UNbalanced Balun, RF Common Mode Choke, 1:1 balun, RF Choke or whatever, yes the objective is to provide a high Z for circulating current on the outside of a coa
With openwire you can build a CMC choke just as easily as with coax. Only thing is, you have to build two of them so it costs twice as much. In fact you make your own coax CMC choke by placing beads
In theory, yes, provided that the choke impedance is much higher than antenna impedance. In practice, this means choke impedance >=10 kOhm, which can be achieved only with special attention, and the
Sinisa, If you will agree to raise that value to 1000 Ohms, then I will agree with you. Often, 1000 Ohms is enough. Steve (G3TXQ) has a nice chart showing impedances for various choke technologies. S
Bob, On the 8231 and 8232, do you know how many beads each type uses? Do you know exactly which bead is used? 73 Rick Semantics.......be it a UNbalanced to UNbalanced Balun, RF Common Mode Choke, 1:1
I don't understand. in coax you are increasing rhe impedence to the common mode current on the shield, right? What would you be doing on the open wire? 73 Dave WA3F With openwire you can build a CMC
Dave, Sorry, my memory failed me there. It was long ago that I did this. I had to search for my notes and drawings (file). Found them. Actually I removed the center cable from coax, and discarded the
Thanks, Rick. Your work is always interresting and I was afraid I needed a cup of coffee, hi 73 es gud DX Dave WA3F -- Original Message -- From: "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de> To: "Discussion
Sorry, I find this a wee bit hard to swallow. I picture a big lump of large toroids, with two plastic pieces of coax jacket going through them, with one wire in each that connect to the open wire. Th
What Rick reported is perfectly sound! If the currents in each of the bifilar pair are balanced - that is they are equal magnitude and opposite phase - there will be no net flux in the core. If they
I have an AS-50-L1 unu;n balun from Array Solutions. Does not matter where I place it problem still exists. -- Jim K9TF _______________________________________________ TenTec mailing list TenTec@cont
I typically place a 1:1 choke transformer at the feed point of my dipole or vertical ground plane, and run coax to a remote relay switch out in the yard, with a single coax to the shack. Am I placing
Jim Brown also has a nice exegesis on the use of toroids which will keep you busy for a while: http://www.audiosystemsgroup.com/RFI-Ham.pdf -- K8JHR -- Steve (G3TXQ) has a nice chart showing impedanc
It's not clear to me what sort of choke you are imagining, but it is trivially easy to build a VERY effective common mode choke by first taping together a pair of insulated conductors to form a paral
Jim, Thanks for the details. I have noted your suggestion for future use. I'm not sure what THHN wire is, but I will google it. I'm sure we have it here, but under a different name. You said ordinary