Re: NE30-40 low power out

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From: PDouglas12@aol.com
Date: Tue Jun 27 1995 - 12:28:46 EDT


Mike,
Yes, I had the same experience. Here's the solution: First make sure the
two coils (L3/L4? -- the ones that clean up the 602 output to the 2n2222's
are right. I got a wrong toroid in there somehow. If you have an
inductance meter, take 'em off and measure them--they are spec'd at 7.8uH but
anywhere around 8uH plus or minus will do. One of mine read a whopping 56uH
which explains why it misbehaved.
   Now, before you do anything drastic like that, do try very carefully
tuning those two little capacitors for max output from the case of the second
2n2222 (clip a lead to it and put it near the antenna -- not touching!-- of
your main station rig. Tune for max on the s-meter. They are interactive,
so go back and forth till you have the real max.) This is done with the
little drive pot turned OFF--counterclockwise.
    Also check: the transformer that carries the rf to the final. And count
the turns on all toroids. Finally, pull the 2n3553 and try a Radio Shack
2n3053--if it gives you about .7 watts, then it is the final and you need
another 2n3553. Also, much of this advice is from Dave Benson NN1G himself,
who is on the list here. He may wish to belay any of the above advice! And
I do not know whether the wrong toroid was my mistake or SWL's, but knowing
what a slob I am when building, I can readily guess! I am posting this to
the group, in case it may help others. I would add that I made over 40 FD
contacts with that little rig on battery power and a dipole, so I am very
very happy with its performance now that I have undone all my errors. And if
you do have a wrong toroid too, please let me know so we can tell Dave and
correct the problem. 72, Preston WJ2V


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