[Elecraft] 9:1 Balun

[Thomas Horsten]

Depends on your random wire and what band(s) you want to use. For some
bands the 9:1 "balun" (not used as a true balun in this case, since both
the coax and the random wire are unbalanced by nature) will step the
feedpoint impedance down to something that's a better match for the 50 ohm
coax, limiting coax losses. It can also allow your ATU to tune up on
frequencies otherwise outside its range. Use the "balun" with a
counterpoise or earth.

In some cases the 4:1 or 1:1 balun may be a better choice, or even
connecting the wire directly to the coax center conductor (and counterpoise
to the shield). All depends on QRG and wire length. If the ATU can tune it
up, you're good to go, if not, change one or more parameters until it can
(wire length, balun ratio, counterpoise length and orientation).

For more information read Dale WB6BYU's answer here:
http://www.eham.net/ehamforum/smf/index.php?topic=33274.0;wap2

73, Thomas OZ5TN

On 31 January 2017 at 07:59, gliderboy1955 via Elecraft <
elecraft at mailman.qth.net> wrote:

> What are the advantages/disadvantages of using a 9:1 balun v. using the
> switchable Elecraft balun at 1:1 or 4:1 or no balun at all when using a
> random wire portable?
> Why 9:1?
> Thanks
> 73 Eric WD6DBM
>
>
> Sent on my Samsung Galaxy S® 6.
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