On Jun 9, 2006, at 3:16 PM, Roy Koeppe wrote:
> " ...is there any non-radio source of appropriate stuff for
> grounding my
> SB-220 grids?...(etc.)"
> Sorry, but I have to bring this up. It seems to me what's good for the
> goose is good for the gander. If low Q parasitic suppressors are
> advantageous for their purpose, then grid straps would be also.
So it would seem, Roy. In my SB-220, using a dip-meter, I madea
before and after resonance f comparison between direct-grounding the
grid pins and grounding them with caps. Not only was the difference
in f only c. 1.3%, which seems pretty insignificant, with the csps
the f was higher, which should mean better VHF stability.
> straps with low inductance
According to Fred Terman, L is a logarithmic function of width, so a
conductor that is twice as wide as another has only slightly less L.
> but not with high Q should tame the grid
> resonances at least slightly. Comes to mind, wide sized "solder wick"
> fully saturated with solder to form a non-stranded, solder-coated
> strap. Easy to obtain as well. It loves to be soldered. And then there
> are tin cans to be snipped into strips??
Since tin exhibits moderate VHF-Q, it seems like grounding the the
grid through 3 chip-resistors might be better.
If you make the mod, it would be interesting to see what you see with
> 73, Roy K6XK
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