On 2/24/2015 6:35 PM, gareth wrote:
"rickman" wrote in message
...
On 2/24/2015 12:37 PM, gareth wrote:
"Spike" wrote in message
...
Get a CW signal peaked on the 20 c/s nose of the HRO crystal filter,
with
the phasing notching out any nearby signal, and you realise that DSP
just
isn't necessary due to the quality of the 80-year-old technology
employed.

WHS.

The Eddystone EA12 does not have a phasing control as that part of the
cct
is fixed-tuned, but it does have a tunable notch in the 100kHz IF to
achieve the same effect.

Mind you, there seems to be a diminishing band of people who know how to
do this, so the simplistic approach of using someone else's
ever-upgraded
software to do something less effective is about as far as the tick-box
Amateur seems to go. Heavens - they even buy ready-made wire aerials!

And going from previous threads, there are even fewer who understand that
setting up for single-signal reception means that the notional carrier
frequency has
to lie half-way between the peak of the Xtal and the notch of the phasing
control.

We should not forget that he who sneers loud and long about others' grasp
of
the mathematics of DSP maintains that changing the direction of a
rotating
vector
(A Phasor, and not related to the weapons of Star Trek!) causes it to
decrease in sixe.

What is "sixe"???

Typo - adjacent key - size

I thought it might be that, but it still makes no sense to me. Who or
how does changing the direction of rotation of a rotating vector change
its "size". Are you defining size as the rotation so that going from a
+ to a - is like reversing the direction of a vector? I think most
people would consider the "size" of a vector to be the magnitude which
is independent of phase angle and so rotation, no?

Perhaps you can explain this with a little math?

--

Rick