Vertex Standard VX-1400, Service Manual, Page: 10 / 66

10 VX-1400 Series Service Manual
Alignment
PA Unit
Preparation
Connect the 50-Ohm Dummy Load and Wattmeter to
the "ANT" jack.
Disconnect the jumper plug from J5007 and J5005 on
the PA Unit.
Set VR5001, VR5002, VR5003, VR5004 and VR5005 on
the PA Unit to fully counter clockwise position.
Press the [ ] / [ ] button to select the "memory chan-
nel 019".
Pre-Drive Stage Idling Current
Disconnect the jumper plug from J5007 and J5005 on
the PA Unit, and then connect the DC ammeter to
J5005.
Press the PTT button; adjust VR5001 on the PA Unit
so the DC ammeter reading is 150 mA ± 10 mA.
Release the PTT button.
Drive Stage Idling Current
Disconnect the jumper plug from J5007 on the PA Unit,
and then connect the DC ammeter to J5007.
Press the PTT button; adjust VR5002 on the PA Unit
so that the DC ammeter reading is 0.5 A ± 50 mA.
Release the PTT button.
Press the PTT button; adjust VR5003 on the PA Unit
so the DC ammeter reading is 1.0 A ± 50 mA.
Release the PTT button.
Final Stage Idling Current
Connect the DC ammeter to the lead of L5008.
Press the PTT button; adjust VR5004 on the PA Unit
so the DC ammeter reading is 1.0 A ± 100 mA.
Release the PTT button.
Press the PTT button; adjust VR5005 on the PA Unit
so the DC ammeter reading is 2.0 A ± 100 mA.
Release the PTT button.
Concluding
Re-connect the jumper plugs to J5005 and J5007, and
then solder the lead of L5008 (It cuts power switch).
CM Coupler Balance
Connect the DC voltmeter between TP5028 (+ lead)
on the PA Unit and Chassis (- lead).
Press the [ ] / [ ] button to select the "memory chan-
nel 021".
Press the PTT switch; adjust TC5001 on the PA Unit
for minimum deflection on the DC voltmeter.
Release the PTT switch.