Icom IC-910H service manual UX-910 Adjustments

5-7 UX-910 ADJUSTMENTS

MEASUREMENT

ADJUSTMENT

ADJUSTMENT

ADJUSTMENT CONDITION

VALUE

POINT

UNIT

LOCATION

UNIT

ADJUST

2ND LO LOCK

1

• Connect an optional UX-910 (1200

MAIN

Connect

a

digital

2.6–3.8 V

Verify

VOLTAGE

MHz band unit).

(UX-910)

multimeter or oscillo-

• Display frequency: 1270.5000 MHz

scope to check point

• Receiving

CP701.

1ST LO LOCK

1

• Display frequency: 1240.0000 MHz

MAIN

Connect

a

digital

6.0–7.0 V

Verify

VOLTAGE

• Receiving

(UX-910)

multimeter or oscillo-

scope to check point

CP501.

2

• Display frequency: 1300.0000 MHz

3.4–4.4 V

• Receiving

RECEIVER

1

• Display frequency: 1280.0000 MHz

MAIN

Connect a spectram

–34 dBm (16 dB gain)

MAIN

R224

GAIN

• Connect a standard signal generator

(UX-910)

analyzer

to

check

(UX-910)

to [12 ANT] connector and set as:

point CP311.

Frequency : 1280.0000 MHz

Level

: 710 µV* (–50 dBm)

Modulation : OFF

• Receiving

ATT GAIN

1

• Display frequency: 1280.0000 MHz

MAIN

Connect a spectram

–14 dBm (20 dB of gain

MAIN

R288

• [ATT]

: ON

(UX-910)

analyzer

to

check

difference between the

(UX-910)

• Set an SSG as

:

point CP311.

attenuator

ON

and

Frequency : 1280.0000 MHz

OFF.)

Level

: 710 µV* (–50 dBm)

Modulation : OFF

• Receiving

IDLING

1

• Display frequency: Any

MAIN

Connect

a

digital

0.5 V

MAIN

R13

• Mode

: CW

(UX-910)

multimeter

between

voltage difference

(UX-910)

• Preset R61, R67, R83 to max.

check points CP321

clockwise, R13 to max. counter

and CP322.

clockwise, and C332 to center.

• Connect an RF power meter to [12

ANT].

• Connect an SSG to the check point

CP311 and set as :

Frequency : 10.8500 MHz

Level

: OFF

• Transmitting

POWER

1

• Display frequency: Any

Rear

Connect

an

RF

5 W

Adjust

BALLANCE

• Mode

: CW

panel

power meter

to [12

SSG’s

• Connect an SSG to the check point

ANT].

level

CP311 and set as :

Frequency : 10.8500 MHz

• Transmitting

2

• Display frequency: 1240.0000 MHz

Read the

RF

power

Verify

• Transmitting

meter indication.

3

• Display frequency: 1300.0000 MHz

Same power as step 2

MAIN

C332

• Transmitting

(UX-910)

4

Repeat step 2 and step 3 several times until power difference is minimum.

TRANSMITTER

1

• Display frequency: 1270.0000 MHz

Rear

Connect

an

RF

5 W

MAIN

R83

GAIN

• Set an SSG as

:

panel

power meter

to [12

(UX-910)

Frequency : 10.8500 MHz

ANT].

Level

: 18 mV* (–22 dBm)

• Transmitting

*This output level of a standard signal generator (SSG) is indicated as SSG’s open circuit.

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