Re: Antenna tuner


Evan Hand
 

Hi Jim,

Before installing the new BS170s, I suggest you verify that IC5 (74ACT08) is still working.  It is easier to test with the BS170s removed.  The best way is with an oscilloscope, but you can get a good approximation by measuring the DC voltage on all of the BS170 gate pads before you install them.  You should read 2.5volts.

73
Evan
AC9TU

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