Yaesu FT-847 Operating Manual page 103

Hf + v-uhf all mode transceiver
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EME ( E
l As the moon sets, the 144 MHz Doppler shift
will approach -500 Hz, so you should adjust the
CLAR control for a negative setting once the
moon passes to the west of your location. At
45º elevation to the west, set the C
about -250 Hz offset to compensate for the Dop-
pler shift on the signal reflected from the reced-
ing moon.
l Doppler shift varies with frequency, so the 50
MHz predicted Doppler shift will be roughly
1/3 of that on 2 meters, while the 432 MHz Dop-
pler shift will be about 3 times the shift on 2
meters.
...
Now tune slowly around the low end of the "CW"
sub-band. On 2 meters, most activity is concentrated
between 144.005 MHz and 144.035 MHz, with the
heaviest activity between about 144.008 MHz and
144.030 MHz. On 432 MHz, the heaviest activity
is between 432.005 and 432.030 MHz. Signals will
be weak (only a few dB above the noise, with small
antennas), so tune slowly.
If you hear a station calling "CQ" you will prob-
ably observe that the call lasts for one to two min-
utes, followed by an identical-length listening pe-
riod. You should reply by sending the other station's
call once or twice, followed by your call for the
remainder of the sending period (one minute, un-
less you know the other station called for two min-
utes). Try to match your sending speed to that of
the other station, and be sure your station's clock
is aligned to WWV, JJY, CHU, VNG, ZUO, or some
other international time standard. On 432 MHz, 2½-
minute calls are sometimes used, especially during
schedules; be sure to match the calling pattern of
the other station.
EME contacts follow a signal report protocol rather
different from that used on HF. The chief compo-
nents of the QSO exchange are:
l "O" means that both callsigns have been re-
ceived.
l "RO" means that the 2nd station has heard both
callsigns (the "O" part), and furthermore that
receipt of the other station's "O" is being ac-
knowledged (the "R" part).
l "R" signifies that all the above information has
been received.
l "73" signifies that the other station's "R" has
been received, and that the contact has now been
completed.
FT-847 O
PERATING
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ARTH
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for
LARIFIER
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ANUAL
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-E
ARTH
PERATION
A typical 144 MHz EME QSO, therefore, might go
something like this, following W1DXC's one-minute
"CQ" call:
(Minute 1)
"W1DXC W1DXC W6DXC W6DXC W6DXC
W6DXC W6DXC ...... KKK"
(Minute 2)
" W 6 D X C W 1 D X C W 6 D X C W 1 D X C
OOOOOOO ...... W6DXC W1DXC KKK"
(Minute 3)
"W1DXC W6DXC RO RO RO RO RO RO .......
W1DXC W6DXC KKK"
(Minute 4)
"W6DXC W1DXC RRR RRR RRR RRR .........
W6DXC W1DXC KKK"
(Minute 5)
"W1DXC W6DXC 73 73 73 73 73 73 73 .........
W1DXC W6DXC SK SK SK"
If the other station repeats a previous transmission (for
example, "OOO"), it means your most recent trans-
mission was not received. Repeat the information
again (in this case, your "RO" transmission) until the
other station acknowledges your information (by send-
ing "RRR RRR" in this case).
EME operation is today within the reach of many more
amateurs than ever before. Good ears, patience, and
commonly-available hardware may be used in conjunc-
tion with your FT-847 to let you experience "The Ul-
timate DX."
Appendix
101

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