> The curious part of this whole business was the location of the heating.
> With turns on BOTH sides of the tap involved, I have to wonder what,
> exactly, was going on there. In the past, when I've melted down tank coils,
> the heating (and deformation) was confined to the center of the active area
> of the coil. Has anyone else seen this effect?
>
IMO, the heating was at the tap point, spreading out each way. Chances are
the "black" area would have spread with time.
There has been mention on the reflector of directing cooling air on a coil
to prevent "melt down." This does nothing about the losses due to under-
engineering. RF is being converted into heat and does not reach the antenna.
Heat can be eliminated by selecting the proper components for the job to
be done. Hans and I are in agreement....there is a limit to how small you can
make an RF deck.
The same is true about band switches. One must take into consideration not
only the voltage and current rating, but also the distance between contacts
when selecting the proper component.
(((73)))
Phil, K5PC
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