[CW] more on the amelia earhart thing

[rb]

I threw out an inquiry of the feasibility of Earhart's using the mike to
send cw from her plane on another forum/reflector.  Here's a few comments;
some apply to the topic, some simply interesting and related:

Neither a vibrator or dynamotor would be powered by a push to talk
microphone switch.

The transmitter needed the vibrator or dynamotor to supply B-plus voltages
to the transmitter and had to be energized before transmitting.  The switch
would also connect the filaments of the transmitter to the aircraft battery
which needed about 20 seconds to heat up before they could send.

The power needs of the radio receiver could be taken care of by connection
of filaments to the aircraft battery and by using suitable B and C cells for
the plates, screen grids and grids of the vacuum tubes.

If the transmitter was keyed by using the microphone button, it was used in
transmit mode - which had the dynamotors cranking - and the transmitter
tubes warmed up and ready.

During periods of extended receiving, the dynamotors were turned off as they
were if they made any "hash" or motor interference to reception.
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My dynamotor rigs did, indeed, spin up the dynamotor each time the PTT was
pressed, but it didn't stop immediately. I don't recall trying it, but I
would be surprised if one couldn't key the rig at, say 8 WPM or faster
without losing HV. It might sag slightly, but I doubt if it'd even do that.
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Hello Folks,
There were some very interesting comments on the equipment used by Earhart
and Noonan and some issues re frequencies used published in the QCWA "Old
Timer's Bulletin".
There is also discussion to the effect that the WE gear was replaced by
Bendix equipment of higher power just prior to the flight. Earhart would
thus have been unfamiliar withthe Bendix.
As I recall, there may have been confusion beween frequencies in kcs and
metres that led Earhart to be on MF instead of HF at the critical times, and
on an unmonitored frequency at that.
There were problems with the ergonomics of this otherwise superb aircraft.
I believe all radios were operated by Earhart from the cockpit, while Noon
was separated from her aft of the big fuel tanks behind the cockpit. If
Noonan had been able to do the radio tasks all might have been well.
Theories about the atoll forced landing are plausible in that Noonan would
have deliberately flown slightly north of the target so as to turn 90 deg
from track in a southerly direction once he had run his distance.
He would not have chosen the alternative as there were islands to the south
if they overshot, but nothing to the north.
It is also plausible that they went on the air on the correct hf frequencies
with seriously reduced power and range after a forced landing.
But plausibility is not proof.
Except for the extreme distance over water flown (for the times) the flight
should have been well within the capabilities of the aircraft and crew.
There is reason to believe that neither Earhart or Noonan were 100% fit when
they took off, but Earhart performed a very difficult short takeoff
flawlessly on the day. There is the possibilty that Earhart became seriously
ill in flight.
Noonan may have been a bit hungover, but he was used to that, and the
navigation tasks were well within his capablities.
They were both very good at what they did.
73
Barry
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More interesting info about Earhart
and Noonan is here at this site.

http://encarta.msn.com/encnet/features/Columns/?Article=AmeliaEarhartMain