On Mon, 28 Dec 2009 18:50:28 -1000, Ken Brown wrote:
>If that was exactly true, there would be only one setting that would
>work. The 238 is not exactly an L network. It is actually a T network
>with two inductors and one capacitor. One of the inductors is very
>small, and in most cases is so insignificant that you can consider the
>238 to be just an L network. In situations where the match is already
>very close on the lower bands, or on the higher bands, either case using
>very little C, you can find a match with either the big inductor at the
>input or at the output. This would be Low Z position 1 or High Z position 1.
>If this were not the case, Jim's earlier post regarding trying both
>possible settings would be incorrect. Only one setting could ever work.
Thanks Ken. You're right, of course. Your post made me return to the manual
and open up the box to look at the second inductor, which is 5 close-spaced
turns of THHN around the (non-conductive) bandswitch shaft. Although I own
six of these tuners, I'd never studied them that closely, except to replace
blown caps and try to restring dial cords. :)
73,
Jim K9YC
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|