Yaesu FT-857 Technical Supplement page 14

Alignment
PLL Unlock
1. Connect the DC voltmeter to TP1029 on the MAIN
Unit (or pin 11 of J2002 on the PLL Unit).
2. Disconnect the REF Unit from the MAIN Unit; con-
firm that the DC voltmeter shows less than 0.5 V and
that "UNLOCK UNLOCK" is displayed on the LCD.
UNLOCK UNLOCK
UNLOCK
3. Re-connect the REF Unit to the MAIN Unit, and con-
firm that the DC voltmeter shows at least 3.5 V and
that the LCD returns to its normal display.
Idling Current Adjustment
Before alignment, set the mode to CW and tune the trans-
ceiver to 1.800 MHz. Nothing should be connected to the
CW Key Jack, and switch off S1001 on the MAIN Unit.
Pre-Driver Stage Idling Current
1. Connect the ammeter between TP1019 (+) and
TP1020 (–) on the MAIN Unit.
2. Press the PTT, and adjust VR1004 for an indication of
30 mA (±5 mA) on the ammeter.
Driver Stage Idling Current
1. Connect the ammeter between TP1017 (+) and
TP1018 (–) on the MAIN Unit.
2. Press the PTT and adjust VR1003 for an indication of
60 mA (±5 mA) on the ammeter.
T1021
T1014
L1049
T1023
VR1005
T1033
14
TP1027 TP1033 T1013 T1012 T1011
MAIN Unit Alignment Points II
Exciter Stage Idling Current
1. Disconnect the Jumper Plug from J1004 on the MAIN
Unit, then connect the ammeter to J1004 (pin 1: –, pin
1: +).
2. Turn both VR1001 and VR1002 fully counterclock-
wise.
3. Press the PTT and adjust VR1002 for an indication of
50 mA (±10 mA) on the ammeter.
4. Press the PTT and adjust VR1001 for an indication of
100 mA (±10 mA) on the ammeter.
5. Re-connect the Jumper Plug to J1004 and switch on
S1001.
TX IF Adjustment
SSB/CW TX IF Adjustment
1. Tune the frequency to the 14 MHz band. Connect the
RF millivoltmeter to TP1033 on the MAIN Unit.
2. Disconnect the Coaxial Cable from J1002 and termi-
nate J1002 into a 50-Ohm dummy load.
3. Inject a 1 kHz tone at 1 mV level to
the MIC jack.
4. Key the transmitter, and adjust T1033
for maximum indication on the RF
millivoltmeter.
5. Disconnect the 50-Ohm dummy load
and re-connect the Coaxial Cable to J1002.
S1001 TP1017
MIC GND MIC
PTT
GND
VR1004
VR1003
TP1018
TP1019
TP1020
VR1002
VR1001
J1004
J1002
J1003