MAINTENANCE 13

■Frequency calibration (approximate)

A very accurate frequency counter is required to calibrate the frequency of the transceiver. However, a rough check may be performed by receiving radio station WWV, WWVH, or other standard frequency sig- nals.

CAUTION: The IC-7700 has been thoroughly ad- justed and tested at the factory before being shipped. You should not have to re-calibrate it.

q Push SSB to select USB mode.

w Push and hold PBT-CLRfor 1 sec. to clear the PBT setting and make sure that the RIT/∂TX function is not activated.

e Set the frequency to the standard frequency station minus 1 kHz.

∫

ACC / √

OTHERS

SET EXIT/SET Main dial

F-1

F-2

F-5

F-7

•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-func-

 

tion screen, if necessary.

• Calibration marker item

t Push [F-7•SET] to select set mode menu screen.

 

y Push [F-5•OTHERS] to enter Others set mode.

 

u Push [F-1•Y] several times to select the “Calibra-

 

tion Marker” item.

 

i Rotate the main dial clockwise to turn the calibra-

 

tion marker ON.

 

o Push

EXIT/SET

once to return to set mode menu

 

screen.

 

!0Push [F-2•ACC] to enter accessory set mode.

 

!1Push [F-2•Z] several times to select the “REF Ad-

 

just” item.

 

!2Rotate the main dial to adjust for a zero beat with

 

the received standard signal as shown at left.

• REF Adjust item

• Zero beat means that two signals are exactly the same

frequency, resulting in a single tone being emitted.

 

!3Turn the calibration marker OFF in Others set

 

mode.

 

!4Push

 

 

 

 

twice to exit set mode.

 

 

 

EXIT/SET

13-5