"SeeingEyeDog" ) writes:
Before satellites became available for eavesdropping the moon was used to
listen to the USSR.

Huh?

The only way you can hear signals bounced off the moon is if they
are aimed there in the first place. That means a deliberate use of
the moon as a passive repeater. It does get around the issue of line of
sight at VHF, but it's not something one can use for "eavesdropping".

Moonbounce was first tried by the US Signal Corp right after WWII, I
think it was 1946. But it needs big antennas and/or high power, and
thus it's really not practicaly until you get into the VHF range of
frequencies. I seem to recall the first moonbounce was around 112MHz.

It didn't take very many years before hams did it, using much less
power and I think smaller antennas. I think it was 1953.

Before there were communication satellites, there were passive satellites
launched where signals were simply bounced off their surface, just
like moonbounce.

There was a time or two in the sixties, after Sam Harris (who had been
one of the better known hams to do moonbounce, but then at the time
it was a relatively small club) moved to Puerto Rico to work at the
radio telescope, that Arecibo was used for amateur moonbounce. With
an antenna that size, there was enough gain that far weaker signals
were receivable, so people with average antennas were able to participate
in the test(s). Sam is credited with the line "if your antenna stays
up all winter, it's too small).

With time, it got easier. Ray Naughton (I spelled that wrong) in
Australia had a lot of space, so he put up stacked rhombic antennas f
for moonbounce, and succeeded even though there was a power limit for
Australian hams at the time of 150Watts or so. His problem was that
the rhombics were fixed, so there was a limited number of days each
month that they were aimed at the moon.

With time, the number of hams capable of moonbounce went up. It became
easier to generate power at the suitable frequencies, and more was
learned about antennas and weak signal work. Solid state helped too,
because they had lower noise figure than most tubes. And once there
were enough with really good stations, it made it easier for others,
because their capability meant that those with smaller antennas could
still do moonbounce.

Michael

"SR" wrote in message
...
The last few evening the moon was almost full and the evening sky was
fairly clear here in New York. I then transmitted on my CB but no DX
only locals.

I read something somewhere that mention about Moon Bouncing. Meaning
that a signal can travel far. But I am not sure if that is true.

73 SR!