..85 nF makes sense.

I've quite a few car radios that had two complete tuners in them, side
by side with LEDs on the board. There were two antenna inputs and you
could plainly see it switch if you changed to the other input. Having
worked on said radio, I think they did a pretty good job at making it
switch without a transient.

The theory is obviously that the multipath is not occurring in two
places at the same time. However, it did not seem as though the AM
section was duplicated in that manner. Looking at these boards, as
this was years ago, they seemed to be strictly FM.

Following the reason, for now, along these lines, there would
obviously have to be a tapoff for the AM section, and this would
operate pretty much like a speaker crossover, just a cap and coil.
Both inputs, although seperate for the FM front ends, would be summed
for the AM section. Not hard to do, pretty much like a summing
subwoofer crossover. Only the frequencies have been changed to protect
the innocent (c'mon it's Sunday).

So, if my summary of the architechture of the radios on which I worked
is correct we can assume the strange capacitor does something to the
phase of the signal, but not to FM frequencies, only to AM
frequencies.

This makes sense because the two antennas are of different size. So
the capacitor makes the two antennae into a basic, unsophisticated,
yet probably effective phased array.

Perhaps someone from Russia will ring in with some ideas on the phase
they actually chose. The value of that cap will determine the
directional sensitivity no doubt. I wonder what pattern they chose,
hmmm, for one it is unreasonable to think that someone would drive
right past the transmitting tower every day, I guess a cardioid
pattern would be good. Actually that holds water because if you are
driving right past the transmitter, what if you want to listen to a
different station ? So cartioid it is right ?

I dunno it might be spelled cardiod or something. I don't feel like
checking right now, but it is most commonly used to describe the
pickup pattern for a microphone. But you had me all screwed up at
first anyway, a 0.85uF cap would serve no purpose except to let a
static charge build up and blow the front end. I don't think that was
their goal.

Oh, the thing about Russia, as far as antennas and things, they are
more advanced than just about anybody. We might have better ICBMs, but
they have better antennas.

So that's what I think it is, the cap brings the two signals into
phase. Then as far as matching the radio to it, they are treated as
one unit.

That's my theory and I'm sticking to it. Pick it apart and I'll
reconsider.

JURB

PS, I love **** like this, WHY did they do this and WHY did they do
that.

JURB