Yaesu FT-891, Technical Supplement

Page: 19 / 99

FT-891 Technical Supplement
Alignment
ALIGNMENT-11
PA Unit Adjustment
Preparation

Connect the Microphone to the Microphone
jack.

C o n n e c t t h e 5 0 - O h m D u m m y L o a d a n d
Wattmeter to the ANT jack.

Disconnect the cable from J5001 on the PA Unit,
then terminate J5001 with a 50-Ohm resistor.

Disconnect the jumper plug from J5003.

Connect the DC ammeter to J5003.

Press and hold the PTT switch, while adjust
VR5001 so the DC ammeter reading is “55 mA
(±5 mA)”.

Release the PTT switch.

Disconnect the DC ammeter from J5003.

Disconnect the jumper plugs from J5005.

Connect the DC ammeter to J5005.

Press and hold the PTT switch, while adjust
VR5002 so the DC ammeter reading is “1.0 A
(±0.1 A)”.

Release the PTT switch.

Disconnect the DC ammeter from J5005.

Connect the DC ammeter to the Power Supply.

Turn both VR5003 and VR5004 fully counter-
clockwise.

Press and hold the PTT switch, while adjust
VR5003 so that the DC ammeter “1.0 A (±0.1 A)”
increase.

Adjust VR5004 so that the DC ammeter “1.0 A
(±0.1 A)” increase.

Release the PTT switch.

Re-connect the jumper plugs to J5003 and J5005.

Disconnect the DC ammeter from the Power
Supply.

Disconnect the 50-Ohm resistors from J5001,
then connect the cable to J5001.
J5001
J5003
VR5002
J5005
VR5001
VR5004
VR5003