Matt - This is usually caused by an improper number of turns on the
output PI network inductors. I had the same, identical problem with my
1330. The coil winding instructions can lead you to put one too many
turns on the coils. This will be stable into a 50 Ohm resistive load,
but any reactance causes the amplifier to take off. I swore that I
hadn't made any mistake, but when I checked I found out that I had
neglected to count the turns as the number of turns through the coil
center. I had mistakenly counted those around the outside edge. This
means that the first entry into the coil caounts as a turn, so what
would seem to be one turn is really two when you complete the loop
through the form. Seems like a long explaination, but after discussing
with tentec, they confirmed that this is the usual cause for this
problem.
Hope this helps, 73 - John
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