TRANSMITTER ADJUSTMENTS (continued)

 

 

 

 

MEASUREMENT

 

ADJUSTMENT

ADJUSTMENT

ADJUSTMENT CONDITION

VALUE

POINT

 

 

 

 

 

 

 

 

 

 

UNIT

LOCATION

 

UNIT

ADJUST

 

 

 

 

 

 

 

 

IF TOTAL

1

• Display frequency: Any

MAIN

Connect an RF volt-

–22 dBm

MAIN

R3

GAIN

 

• Mode

: USB

 

meter to check point

 

 

 

 

 

• MIC gain

: Center

 

J51 via the JIG cable

 

 

 

 

 

• Disconnect P501 (PA unit) from J51

 

(B).

 

 

 

 

 

on the MAIN unit.

 

 

 

 

 

 

 

 

• Connect an audio generator to

 

 

 

 

 

 

 

[MIC] connector and set as:

 

 

 

 

 

 

 

Frequency

: 1.5 kHz

 

 

 

 

 

 

 

Level

: 2 mVrms

 

 

 

 

 

 

 

• Transmitting

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

After adjustment, connect P501 (PA unit) to J51 on the MAIN.

TOTAL GAIN

1 • Display frequency:

Rear

Connect an RF

50 W

PA

R503

(for 144 M)

[EUR], [KOR]

 

145.0000 MHz panel

power meter to [VHF

 

 

 

 

[USA-1], [AUS]

 

146.0000 MHz

ANT] connector.

 

 

 

 

• Mode

:

USB

 

 

 

 

 

• RF power

:

Maximum

 

 

 

 

 

• MIC gain

:

Center

 

 

 

 

Connect an audio generator to [MIC] connector and set as:

 

 

Frequency

:

1.5 kHz

 

 

 

 

 

 

 

Level

:

2 mVrms

 

 

 

 

 

 

 

• Transmitting

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(for 430 M)

2

• Display frequency:

 

 

Connect an RF

37.5 W

 

R3

 

 

[EUR], [KOR]

 

435.0000 MHz

 

power meter to [UHF

 

 

 

 

 

[USA-1], [AUS]

 

450.0000 MHz

 

ANT] connector.

 

 

 

 

 

• Transmitting

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Ic APC

3

• Display frequency:

146.0000 MHz

Rear

Connect an ammeter

23 A

MAIN R1613

 

 

• Mode

:

USB

panel

(30A) between power

 

 

 

 

 

• Connect CP1631

(MAIN unit) to

 

supply and the IC-

 

 

 

 

 

GND.

 

 

 

910H.

 

 

 

 

 

• RF power

: Maximum

 

 

 

 

 

 

 

• Mic gain

: Center

 

 

 

 

 

 

 

• Connect an audio generator to

 

 

 

 

 

 

 

[MIC] connector and set as:

 

 

 

 

 

 

 

Frequency

:

1.5 kHz

 

 

 

 

 

 

 

Level

:

20 mVrms

 

 

 

 

 

 

 

• Transmitting

 

 

 

 

 

 

 

After adjustment, disconnect CP1631 (PA unit) from GND on the MAIN.

DRIVE LEVEL 1 • Display frequency: 146.0000 MHz

MAIN Connect an RF volt-

Read the RF voltmeter

Verify

• Mode

: USB

meter to check point

indication.

 

• RF power

: Maximum

J51 via the JIG cable

 

 

• Mic gain

: Center

(B).

 

 

Disconnect P501 (PA unit) from J51 on the MAIN unit.

Connect an audio generator to [MIC] connector and set as:

Frequency

: 1.5 kHz

Level

: 20 mVrms

• Transmitting

 

2 • Mode

: CW

Same level as step 1 MAIN

R202

• CW paddle

: OFF

 

 

Connect a keyer to the [KEY] jack.

Key down (transmitting)

After adjustment, connect P501 (PA unit) to J51 on the MAIN.

LO LEAK

1 LO leak must be performed after software adjustment (7) “TX POWER/METER”.

 

(for 144 M)

 

• Display frequency:

Rear

Connect an RF

Minimum output power

PA

R504

 

 

 

 

[EUR], [KOR]

146.0000 MHz

panel

power meter to [VHF

 

 

 

 

 

[USA-1], [AUS]

148.0000 MHz

 

ANT] connector.

 

 

 

 

 

• Mode

: USB

 

 

 

 

 

 

 

• RF power

: Minimum

 

 

 

 

 

 

 

• MIC gain

: Center

 

 

 

 

 

 

 

• Transmitting

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

5 - 10

Page 28
Image 28
Icom IC-910H service manual If Total, Main Gain, Gnd, LO Leak

IC-910H specifications

The Icom IC-910H is a highly regarded and versatile transceiver that is designed for amateur radio operators who are particularly interested in V/UHF and microwave communications. Known for its exceptional performance, the IC-910H encompasses a suite of features that make it a standout choice for both casual and dedicated hams.

One of the main features of the IC-910H is its dual-band capability, allowing for simultaneous operation on both 144 MHz (2 meters) and 430 MHz (70 centimeters) bands. This dual operation enables users to engage in various communication modes, including SSB, CW, FM, and digital. Its high frequency stability ensures that users can rely on the transceiver for accurate and consistent transmissions.

The IC-910H is equipped with a high-performance 10 MHz IF filter that improves selectivity and reduces adjacent channel interference. The optional 1.2 GHz module enhances the transceiver’s capabilities, allowing operators to venture into microwave frequencies. This expandability is a significant advantage for users who wish to progress in their amateur radio pursuits.

Another notable aspect of the IC-910H is its large, easy-to-read LCD display, which features various color options for enhanced visibility. The front panel layout is user-friendly, providing quick access to important controls and functions. The built-in DSP (Digital Signal Processing) technology offers noise reduction and filtering capabilities, significantly improving overall audio quality and making weak signals more intelligible.

The transceiver also includes extensive memory functions, with up to 1,000 memory channels available for storing frequencies, modes, and operational settings. Additionally, it supports CTCSS and DCS tones, which facilitate the use of repeater systems and private group communications.

In terms of build quality, the IC-910H features a robust construction designed for durability and long-term use. Its efficient power supply management ensures excellent performance while minimizing heat generation, making it suitable for extended operating sessions.

Overall, the Icom IC-910H is a powerful and feature-rich transceiver that is favored by many amateur radio enthusiasts. With its versatile operating modes, advanced filtering capabilities, and clear display, it stands out as a reliable tool for both casual operators and serious DXers. Its well-thought-out design and comprehensive features make it a valuable addition to any ham's station collection.