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16-4
16
MAINTENANCE
A very accurate frequency counter is required to cal-
ibrate the frequency of the transceiver. However, a
rough check may be performed by receiving radio sta-
tion WWV, WWVH, or other standard frequency sig
-
nals.
CAUTION:
The transceiver has been thoroughly
adjusted and tested at the factory before being
shipped. You should not have to re-calibrate it.
q
Push
the Mode key [SSB]
to select USB mode.
w
Hold down [PBT CLEAR] for 1 second to clear the
PBT setting and make sure that the RIT/
∂
TX func-
tion is not activated.
e
Set the frequency to the standard frequency station
minus 1 kHz.
• When receiving WWV or WWVH (at 15.00000 MHz) as
a standard frequency, set the operating frequency for
14.99900 MHz.
• Other standard frequencies can be used.
r
Push [EXIT/SET] several times to close a Multi-
function screen, if necessary.
t
Select the “Calibration Marker” item in the Display
set screen.
SET
[F-7]
OTHERS
[F-5]
Calibration Marker
y
Rotate [MAIN DIAL] clockwise to turn the calibra-
tion marker ON.
u
Push [EXIT/SET] once to return to the
Set mode
menu screen
.
i
Select the “REF Adjust” item in the
ACC set
screen
.
SET
[F-7]
ACC
[F-2]
REF Adjust
o
Rotate [MAIN DIAL] to adjust for a zero beat with
the received standard signal as shown at left.
• Zero beat means that two signals are exactly the same
frequency, resulting in a single tone being emitted.
!0
Turn the calibration marker OFF in the Others set
mode.
!1
Push [EXIT/SET] twice.
• Exits the Set screen.
■
Calibration the Frequency (approximate)
• Calibration Marker item
• REF Adjust item
(F) Function keys [EXIT/SET] [MAIN DIAL]