[Elecraft] Balun for K-1

[Tom Hammond NØSS]

Hi Jim:

>I think it is unecessarily complicated for the task at hand. For the use
>over the short frequency span of interest to a K-1 4 band module user, 7 MHz
>to 21 MHz,  a simple coiled coax choke balun, 6 or 7 turns should provide
>adequate choking reactance. It is simple, can be made in minutes, and is
>effective. With it you can be on the air in minutes. The numbers you quote
>indicate the effectiveness of the simple coiled balun, the balun in column
>5, 8 turns sceamble wound into a 6 5/8 in coil, has a peak choking reactance
>of 8530 ohms and a 200 Ohm choking reactance bandwidth (recommended by
>deMaw) from 2 MHz to 16 MHz (an 8:1 bandwidth. There are those who think a
>200 Ohm reactance bandwidth is inadequate, so the 500 Ohm choking reactance
>bandwidth is from 3.5 MHz to 10.5 MHz, still a respectable 3:1 ratio.
>Winding a coiled coax choke balun as I suggested should be adequate for the
>4 band K-1, which was the application I was addressing. Other applications
>may require more care and a better balun. When improvements are made to the
>antenna system at a later time, the balun can be upgraded. But to get on the
>air quickly with a minimum of fuss and acceptable performance, the coiled
>coax balun is hard to beat.

I agree completely with your response!

I was mainly posting the article for the benefit of all of us on the 
reflector, rather than directing it at anyone is particular.

Of course, MANY (thousands, I'm sure) scramble-wound baluns have been made 
over the years (my tribander sported one for probably 15-18 years itself). 
And we never knew the difference between the way it worked and the way it 
might have performed had it been wound in a solenoidal fashion. Heck... we 
STILL don't now... <G>

But, thanks to the article, I now know that if I want to obtain PEAK 
performance from my coaxial-cable baluns, I should probably wind them in a 
single-layer coil, rather than in the manner I'd been using for many years. 
As you state, in many instances a single-layer coil is not required to 
obtain more than adequate performance.

>The posting was in keeping with my QRP KISS (Keep it simple stupid) policy.
>I find the KISS policy keeps me out of trouble and on the air more than
>pursuing optimum (and oftem more complicated) solutions. Don't get offended,
>the stupid in KISS is not meant to apply to anybody but me.

I'm not offended in the least... and I do appreciate your further 
discussion (above) of the subject. Thanks for taking the time to respond. 
And, don't worry, MOST CERTAINLY applies to me very well...!!

73,

Tom Hammond   N0SS