Re: Difficulty during alignment - RF output #qcx #problem #20m


Ronald Taylor
 

Alan made a great point about the possibility of open circuit BS-170s. Since you are paying shipping costs, you should probably order a handful of those as well. It looks like they are functioning somewhat from the explanation you gave but if the lowpass filter indeed tests good, then there should be power output, even though there is constant DC (not keyed on and off) at the drains. So remove the Q1, Q2, Q3 and Q6 while waiting for the parts to arrive. Install the new Q6 first. Check on the empty drain pad of Q1 (pin 1 in your drawing) for DC only when key is pressed. Also check on the empty gate pad (pin 2 in your drawing) for 2.5 V when the key is pressed. If both of those are correct, install Q1, Q2 and Q3 and test. 

Ron

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