On Fri, 12 Mar 1999 13:56:39 -0600 "Roy Koeppe" <royanjoy@ncn.net>
writes:
>
>Hello,
>
>A trick I learned for testing them another, reassuring way is to mount
>them
>into position, with the "bottom" grounded. Then dip the tank's
>resonant
>freq. both with and without the "top" connected to the tank. A
>high-performance choke should be nearly "invisible" or "transparent"
>to the
>tank's resonant freq.
An excellent hint Roy.
>
>160M is often a special case, as many chokes have reactance reflected
>into
>the tank due to too high of a fundamental parallel self-resonant freq.
>of
>the choke. This causes the need for more C1 capacity in the pi-net,
>and
>increased circulating currents in the choke itself.
Translated: Too little choke L to get all the RF going in the wanted
direction. Thats a problem with several amps that try and cover 9 bands.
Enough L for 160M and smoke on some higher band and vice versa.
73 Carl KM1H
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