On Jun 3, 2006, at 10:54 AM, Gudguyham@aol.com wrote:
> In a message dated 6/3/2006 1:49:18 PM Eastern Daylight Time,
> email@example.com writes:
> The main issue with SB-220 band switches is because of the front
> layout, the band switch gets turned instead of the loading control
> in tune-up mode.
> YES THIS COULD BE A PROBLEM, BUT THAT DOES NOT ACCOUNT FOR THE 10
> METER AND
> 15 METER CONTACTS BEING BLOWN AWAY.
Good point, Lou The reason that the 10m and 15m L contacts get
toasted is because 110MHz can not go much beyond the input end of the L.
> The very late SB-220s and HL-2200s had longer tune caps. Or Heathkit
> made them available on a replacement basis. I have seen several
> with them.
The TL-922 also uses a 4500v Tune-C. To protect the bandswitch from
arcs, I bent the first rotor plate until the breakdown potential
dropped tp 3500v, which is still c. 900v higher that the actual peak
AC anode voltage.
> OF THE DOZENS I HAVE SEEN INCLUDING HL-2200'S THIS WAS NOT THE
> CASE ALTHOUGH
> I NEVER TOOK MEASUREMENTS MY FEELING IS THEY WERE ALL THE SAME.
> 73 LOU
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