On Fri, 28 Oct 2005 11:02:18 -0400, TRABEM wrote:
Is my mission to purposely isolate the loop so that anything happening
in the receiver doesn't impact the loops Q?

The advantage of Q is that it multiplies I and V giving you
sensitivity. As I have pointed out before, your current design could
work without any changes. I cannot answer this for myself much less
you and the advice I would have to offer is that you build your
receiver with flexibility in mind. We are not talking big changes in
components. That is the long answer. The short answer is yes.

If this is the case, an active buffer amp seems inevitable.

Easy enough to include, or remove depending on need.

If I do not buffer the loop from the RX, wouldn't a 2K loop fed into a
2K RX also cause similar loss of Q (just like the 2 ohm over 2 ohm
example you gave previously)?

Certainly, but not similarly. The Q is not going to plunge to 2 or 3.

And, I am definitely not avoiding the I/Q issue. I know of successful
hardware handling examples of the I/Q and also of successful software
handling methods. I just haven't decided which one to use yet.

That is the point of my questions. They are veiled implications, not
tests of knowledge. No one in your list of links, much less those
I've read over the years knows the PRACTICAL implication of the "I"
and "Q" channels. So, I may as well drop the other shoe.

One does the demodulation of AM signals, the other provides
demodulation of FM and SSB signals. I'm not sure which and what
particular arrangement of supporting circuitry is required beyond
simple AM amplifiers because my construction for that application was
back in 68-69. Building tube models and guaranteeing design
considerations was not as simple as the Tayloe circuit offers now.

However, one of the fascinating characteristics of this style of
detector is that you can feed each channel to the earpieces of a
stereo headset. "I" for one, "Q" for the other earpiece. This gives
you the chance to use your wet-ware instead of someone's software and
hardware.

The brain does all the necessary fourier analysis automatically and in
real time. The upshot of it is that when listening to a CW signal,
and hearing the field of signals around it, you perceive those signals
in a mind-space. The signal that is center tuned sounds like it is
between your ears, in the middle of your, as I described it,
mind-space. Those signals that are above it in frequency sound as
though they are coming from the right, and those signals that are
below it in frequency sound as though they are coming from the left.

The advantage of this detector, in this configuration, with this kind
of perception, is that your mind is separating the signals
psychologically. Even though the signals you hear on the left and
right are in equal amplitude to the center, you can exclude them
mentally. Imagine taping a conversation in room full of people and
the microphone is not at your, or your partners lips, but between you,
and you are both standing off a couple of feet talking over the crowd.
You full know that you could understand your partner at the time of
the recording, and you probably know that the tape would be a bitch to
make sense of, even though it makes a faithful record of the
conversation in that free-for-all.

The difference is that your binaural perception with its phase
separation capability could be brought to bear to ignore the field of
noise to concentrate on your partner. When you hear the mono
recording, the phase information is lost and your partner's
conversation merges with the background noise.

I cannot personally vouch for this effect because the payoff in my
construction back then didn't come down to finally evidencing this
effect for myself. This wet-ware characteristic was reported to me to
be one of the attractions of building for my professor. I have also
played with bucket-brigade delay lines to create this effect. At one
time Paul McCartney was using it with his music. Aural phase
relationships have a strong psychological information content that is
taken for granted.

73's
Richard Clark, KB7QHC