[Johnson] Neutralization

[Richard Peterson]

Let's be careful here that we not confuse curing VHF parasitics with 
neutralization -- these are apples and oranges.

Regardless, it was said in some of the older ham literature that screen grid 
tubes were awesome inventions because neutrtalization was not required -- 
the screen isolated the elements of the tubes. That is true to some extent 
-- but I have found that most rigs with tubes such as the 6146, or even a 
4-400, needed neutralization.

Now, how do I know this? There is a simple way to find out: If the maximum 
power output does NOT occur at the plate dip, the final likely needs 
neutralization, or the neutralization requires adjustment. On the other 
hand, if the plate dip and maximum power output occur at the same point, 
then you either do not require neutralization, or the neutralization circuit 
is properly adjusted. In truth, I have found it is possible to operate rigs 
that are not "on the money" in this regard.

I hope this helps.

- Richard, WB5NEN

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