Rich Measures wrote:
> ? I did not state that the arcs occurred during 10m operation. I stated
> that the arcs occurred at the open 10m contacts. The photo of the
> toasted bandswitch in the QST article "Parasitics Revisited" Sep.,
> Oct./1990) shows a bandswitch that was damaged during 40m and 80m
> operation, when the 10m, 15m and 20m contacts were open. In the
> photograph, the 10m contacts are those with the most damage. The 20m
> contacts are the least damaged.
> - later
-------------------
I first worked on an SB220 as a Heathkit tech in the mid 70's.
Since then I've owned, serviced, modified or for some reason had
my hands inside 20 or 30 SB220s (not the 200 Rich has tested).
In the 220s Ive worked on with bandswitch damage that damage
can be directly attributed to the operator rotating the band switch
instead of the load control while tuning up. The physical layout
of the tune, load and bandswitch controls makes it easy to turn
the wrong knob and cause the "parasitic" damage.
73, Bob, W5AH
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