> but rather some other problem. Maybe it has something
> to do with the linearity of the detector and audio stages
> as Tom, W8JI suggested.
I wasn't suggesting any problem specific to the Orion. I was suggesting
general causes of different ability to receive noise floor signals, which
certainly exists.
Poor weak signal reception can be caused by low gain or poor gain
distribution, filter group delay problems, and detector and audio problems.
One specific example is my IC751A, which measures very good on a bench but
stinks in real life operation. An operator who (through lack of training or
whatever) can not copy CW signals with a near zero-dB S/N ratio, would never
notice the flaws in the 751A because they only show up on narrow CW filters
on signals that are in or near the noise floor.
I personally would not rank close receivers, even against a baseline
receiver, at a different hours or especially different days because of the
many variables involved unless one was very obviously worse.
This is leading me to think of a better test, to intentionally inject
controlled repeatable noise and have an off and on CW signal sending random
text.
73 Tom
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