Kenwood TS-820 Marine Radio User Manual


 
6.4
ADJUSTMENT OF TRANSMITTER
SECTION
ADJUSTMENTOFTRANSMIT DRIVE COIL
(COIL PACK UNIT)
The drive coil is built in the coil pack unit. Set the SG switch
on the rear panel to OFF and the DRIVE knob to its center
position. Then. set the METER switch to ALC and the
MODE switch to CW or TUN position.
With the standby switch in the SEND position, adjust the
drive coils for maximum ALC deflection for each band using
the same frequency as for the adjustment of ANT and MIX
coils.
During the adjustment. turn the CAR knob just enough to
swing the meter
(ALC). This adjustment can be started with
any band.
ADJUSTMENT OF TRANSMIT IF
COIL
(IF AND RF UNITS)
Using any frequency. set
the transceiver in transmit mode at
CW or TUN position. Adjust T5 of the IF unit and
T1 of the
RF unit until the meter
IALC) indicates maximum deflection.
CARRIER BALANCE ADJUSTMENT (IF
UNIT1
(See Fig.
31)
With a dummy load connected to the ANT terminals. adjust
for the maximum output using
14.175
MHz frequency.
Set
the transceiver in LSB mode and turn the RF VOLT
knob.on
the rear panel for maximum sensitivity. The pointer of the
RF meter will deflect if the carrier is unbalanced. In this
case, be sure to turn the MIC knob to the minimum position.
To balance the carrier. adjust the trimmer
TC1 and the semi-
fixed resistor VR2 alternately until the meter pointer in-
dicates a minimum position. Change the mode to USB and
if the pointer deflects. then readjust so that the pointer
deflects the same amount for both LSB and
USE.
NEUTRALIZING THE FINAL STAGE
Adjust the drive and final stages completely using
21.3
MHz. with a dummy load connected.
Set the SG switch to OFF and measure the output at the
ANT terminals (shorted with dummy load) with a high sensi-
tivity RF voltmeter or a tester having a rectifying diode such
as 1
N60. Then turn the nuetralizing variable capacitor lTC1
viewed through the adjusting hole in the upper panel of the
final box) for minimum output. Normally. it is unnecessary
to remove the shielding case for this adjustment, but be sure
to use a insulated screwdriver. Use of a non-insulated
screwdriver will result in incorrect adjustment and also
cause electric shocks.
ADJUSTMENT OF SIDE TONE LEVEL (AF-AVR UNIT)
Adjust VR3 to your desired level.
ADJUSTMENT OF MONITOR LEVEL (IF UNIT)
Adjust VR4 to your desired level.
Fig. 31 Counter Frquency Calibration