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Old December 16th 05, 02:15 AM posted to rec.radio.amateur.policy,rec.radio.amateur.misc,rec.radio.amateur.dx,rec.radio.amateur.boatanchors
Tom
 
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Default Astro-net from the 60s

Sorry, out of town for a few weeks.

The Astronet guys observed that the flashes were conicident
both in time and location on the moon when observed from various
locations up and down the west coast. Conclusion was that the flashes
were meteor impacts on the lunar surface. I think this was later
confirmed independently.

One of the guys had an interesting 80m setup. Separate Tx and Rx,
and 1kw amplifier. He had an separate Rx antenna, an IF output
jack on the Rx, and an electronic TR switch on the Rx.

He would connect an oscilloscope to the IF output of the Rx, and
hit a few dits on the keyer. You could see the transmit waveform
as full-screen signal, then nothing as the Rx recovered back into operation
after a few tens of microseconds. Then you could see the backscatter
pop up on the receiver scope. The keying rate had to be fast enough
and completely synchronous to see it on the non-storage scopes of the
day. But he was able to measure the time to receive the echos back
from the ionosphere and pretty much could predict whether he should
bother operating the net that night (with reasonable accuracy). The echos
were somewhat smeared out, so the return signal was undergoing a somewhat
distributed reflection process.

I don't recall if the backscatter was normally TX-Ionosphere-Rx or if
it was Tx-Ionosphere-Ground-Ionsphere-Rx
My recollection is that he had seen both cases.

-- Tom





"Mike Andrews" wrote in message
...
And that conclusion was?

Gonna just leave us haning like that?

In rec.radio.amateur.boatanchors Tom wrote:
You bet. They started out when some of the guys noticed brief
point-source
bright flashes
on the lunar surface. Used 80m to time whether the flashes were
synchronized
across
large observation distances. If they were not, then the flashes were
likely
meteors in
the earth's atmosphere; if they were synchronized, then the probablility
that they were
associated with an event on the lunar surface was pretty high.


The guys had scopes setup in the backyard and 100-foot
headphone/microphone
cables
going back to the radio so they could observe and talk on the radio
simultaneously.


They did reach a conclusion about the flashes....


"Jeffrey Herman" wrote in message
...
"Bob Sherin, W4ASX" wrote in message
To be honest, I never felt comfortable on 75 meters, nor did I feel
that I fit in for the most part. There were groups, however, in which
I enjoyed participating,

Anyone remember the Astro-Net on 3885 kc from the 1960s? It was composed
of group of amateur astronomers who nightly trained their telescopes on
a
particular celestial object and would then have round-table comments
about that object. It was fascinating to eavesdrop on that net.

73, Jeff KH6O
--
Chief Petty Officer, U.S. Coast Guard
Mathematics Lecturer, University of Hawaii System


--
Mike Andrews, W5EGO

Tired old sysadmin