Hi Greg,
> If it does not blow apart with the sound of a 12 gauge or steadily lose
> power with a corresponding rise in SWR like all the W2DU type baluns I
> have ever owned, then it's probably an ok balun. The only time I had no
> problem with the less expensive bead type baluns was with 100w or less.
> You would do well to read "Baluns & UnUns" I have several of the toroid
> type baluns using the high power Teflon coax and the only problem I have
> with those is finding a suitable enclosure which is strong and
> lightweight.
The exact reason we need to know Rp of the balun, and do a little
Ohm's law work with Rp.
I've had exactly the same results as you, and a "paper review"
predicts the balun should overheat just as it does.
There are good applications for strings of beads, but QRO
operation is not one of them because the string needs to a higher
Q bead and MANY more beads than anyone would ever expect.
Even 10 watts of bead dissipation will send the beads into 3 Mile
Island effect unless it is a LONG string.
73, Tom W8JI
w8ji@contesting.com
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