>
>> The problem in the Heath SB-1000 switch arcing IMO
>> is due to the layout and the Tesla effect. If the 80-160 meter tank coil
>> had been wound on a torroid, the problem would have been solved. Just too
>> much coil in too little space. As the inadequate padder door knobs change
>> value due to heat, the problem will raise its ugly head by burning out the
>> band switch. The addition of the washer on the switch contact is not
>> enough to overcome the inevitable when values start to change in the
>> padders. Ameritron has solved this problem by using robust mica caps as
>> padders, which fit nicely into the SB-1000.
>>
>> IMO, the Tesla effect is the culprit in arcing switches.
>
>The SB1000 had about 50 times the switch failures (as determined
>by parts shipped to customers) of the nearly identical AL80A.
>
>The reasons were:
>
>1......
>
>3.) No anti-corona washer at an area in the switch where voltage
>gradient is a problem.
>
3000v corona. Give us a break. . I have spoken with a number of owners
who were experiencing intermittent arcing with the anti-corona washer
installed. Arcing reportedly stopped when the VHF Q of the suppressor
was lowered. /arced bandswitch photos are on my Web site./
end
- Rich..., 805.386.3734, www.vcnet.com/measures.
end
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