On Apr 29, 4:30*pm, Michael Coslo wrote:
K1TTT wrote:
On Apr 28, 6:45 pm, Michael Coslo wrote:
Richard Clark wrote:
On Wed, 28 Apr 2010 10:11:51 -0700 (PDT), Bill wrote:
how useful is the discussion to the average reader of r.r.a.a.?
Hi Bill,
Well, diversity antenna work is quite useful to the average reader - I
suppose (they haven't actually clamored for the discussion or
embroiled themselves in the topic, but you did couch this in terms of
"readers").
Sure, at least in a practical sense. I make use of diversity receivers
in wireless microphone work.

While these are used at UHF frequencies rather than HF, our problems are
more multipath, maybe picket fencing a bit.

So while I know better than to get into the definitions of diversity
antennas, given my meager abilities, *my guess is that if one antenna
worked better than two - or merely worked at all, we'd be using just one.

Tom's pseudo stereo looks suspiciously like a wetware version of my
wireless systems,only that they vote, whereas his signal levels are too
low for that, so he does it in his head.

Unfortunately, if we divorced the two authors who fail to offer what
Diversity means, apart from what is already accepted in convention,
then we remove the entertainment value and "readership" would likely
decline.
That is for certain.

A paradox.
One of my favorite words.

if the pseudo stereo is derived from 2 different antennas then you
have diversity reception where the separate antennas provide different
signals that may fade at different times due to polarization changes
or incident angle changes... that is what tom was driving at as a
useful diversity system, albeit at the expense of more complex
receiver hardware.

Yeah, I think I agree with Tom's practical experience/experiment. I
certainly do not think that one antenna is going to do this diversity,
because if it would, it means that there is no need for any of the
diversity systems we know about today, with double antennas, voting
and/or dual receivers.

Richard's concerns are for the definition, which I think in Art's case,
is probably important.

* when you take a single rf signal and split it through different

receive processors to shift the phase, or do different sidebands, or
just run through different high/low pass audio filters, you don't
really have diversity, you have some kind of a processing system that
makes it easier for your brain or some other decoder to sort out the
signal from the noise. *I played with some simple ones years ago

side foray here. Did you try binaural receivers? I've heard of them,
never had a chance to listen to one.

i tried a few combinations of audio high pass/low pass and different
ssb in each ear. there are some interesting effects you can get that
way that give you spatial effects as you tune across the band. you
can get the feeling that the signals come in one ear and out the other
as you tune across them... interesting once you get used to it on cw,
but probably not much use on other modes.