Icom IC-910H service manual RF Peak, TX Power

Page 34

SOFTWARE ADJUSTMENT (continued)

ADJUSTMENT

ADJUSTMENT CONDITION

 

DISPLAY

OPERATION

 

 

 

 

 

 

ADJUSTMENT

1

• Enter software adjustment mode (Refer

 

 

Push [RIT] key to strat transmitting.

 

USB

ITEM (6)

 

page 5-12).

 

 

 

 

RF PEAK

 

• Push [6] key to enter the RF peak adjust-

 

 

 

 

 

ment for TX.

 

 

 

 

 

 

• Connect an RF power meter to [VHF ANT]

 

 

 

 

 

connector.

 

 

 

 

 

 

 

 

 

 

 

2

 

 

USB

• Pushing [SET] key, tune the [MAIN

 

• Connect an SSG to P501 on the PA unit

 

 

 

 

 

 

 

 

 

via the JIG cable (A) and set as:

 

 

DIAL] to maximum.

 

 

 

 

• Adjust L501, L502 on the PA unit

 

 

Frequency : 10.850 MHz

 

 

 

 

 

 

(illustration for location page 5-9) to

 

 

Level

: 18 mV* (–22 dBm)

 

 

 

 

 

 

maximum.

 

 

Modulation : OFF

 

 

 

 

 

 

• Pushing [SET] key, tune the [MAIN

 

 

 

 

 

 

 

 

 

 

 

 

NOTE: While transmitting, adjust SSG’s

 

 

DIAL] to maximum, then push [RIT]

 

 

level and keep the output power less than

 

 

key to store peak setting into mem-

 

 

30 W.

 

 

 

ory and to step next.

 

 

 

 

 

 

 

 

3

 

 

 

USB

(1) Pushing [ATT] key, tune the

 

 

 

 

 

 

[MAIN DIAL] to maximum.

 

 

 

 

 

 

(2) Pushing [SET] key, tune the

 

 

 

 

 

 

[MAIN DIAL] to maximum.

 

 

 

 

 

 

(3) Repeat (1) and (2) several times

 

 

 

 

 

 

until output power will be peak,

 

 

 

 

 

 

then push [RIT] key to store peak

 

 

 

 

 

 

setting into memory and to step

 

 

 

 

 

 

next.

 

 

 

 

 

 

 

 

4

 

 

 

USB

Same as step 3. Then turn power

 

 

 

 

 

 

OFF and ON to return the normal

 

 

 

 

 

 

operation mode. Then continue to

 

 

 

 

 

 

adjust from step 4 of the RF PEAK

 

 

 

 

 

 

adjustment (page 5-8).

 

 

 

 

 

 

 

 

 

 

 

 

 

ADJUSTMENT

1

• Enter software adjustment mode (Refer

 

 

Push [RIT] key to strat transmitting.

 

CW

ITEM (7)

 

page 5-12).

 

 

 

 

TX POWER/

 

• Push [7] key to enter the TX power/meter

 

 

 

METER

 

adjustment.

 

 

 

 

(for 144 M)

 

• Connect an RF power meter to [VHF ANT]

 

 

 

 

 

connector.

 

 

 

 

 

 

 

 

 

 

 

2

 

 

CW

Tune the [MAIN DIAL] to 100 W

 

 

 

 

 

 

 

 

 

 

(High power). Push [RIT] key to

 

 

 

 

 

 

store the adjustment value into

 

 

 

 

 

 

memory, and to step next.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3

 

 

 

CW

Tune the [MAIN DIAL] to 50 W

 

 

 

 

 

 

(Middle power). Push [RIT] key to

 

 

 

 

 

 

store the adjustment value into

 

 

 

 

 

 

memory, and to step next.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4

 

 

 

CW

Verify the output power (Low power)

 

 

 

 

 

 

is 1–5 W, then push [RIT] key to step

 

 

 

 

 

 

next.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(for 1200 M)

5

• Connect a

digital multimeter or oscillo-

 

 

Push [RIT] key to strat transmitting.

 

CW

 

 

 

 

 

 

 

 

scope to check point CP1631.

 

 

 

 

 

 

 

 

 

 

6

CW

Tune the [MAIN DIAL] to 3.0 V at the

 

 

 

 

check point CP1681. Push [RIT] key

 

 

to store the adjustment value into

 

 

memory, and to step next.

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

5 - 16

Image 34
Contents Service Manual Repair Notes IntroductionOrdering Parts EURTable of Contents Specifications GeneralReceiver Main and PLL Units SectionInside Views FM if ICPA Unit Bottom View TOP ViewPLL IC Opening the transceiver’s case Disassembly and Option InstructionsUX-910 1200MHz Band Unit FL-132/FL-133 CW Narrow Filter Opening the PA unit coverMain SUB UT-102 Voice Synthesizer Unit Installing 1st DSP unit front panel sideInstalling 2nd DSP unit rear panel side UT-106 DSP UnitCR-293 High Stability Crystal Unit Circuit Description Receiver CircuitSquelch Control Circuit Main Unit 6 10 MHz if Circuit Main UnitDemodulator Circuit Main Unit Squelch Circuit Main UnitAGC Circuit Main Unit Transmitter CircuitsNoise Blanker Circuit Main Unit Meter Circuit Main UnitCW Keying Circuit Main Unit Transmit if Amplifier Circuit Main UnitModulation Circuit Main Unit RF Circuit PA UnitPLL Circuits 7 1LO PLL Circuit PLL Circuits8 2LO PLL Circuit Required Test Equipment Adjustment ProceduresPreparation Before Sarvicing ‘ ConnectionsPLL Adjustments Frequency AdjustmentPLL and Main Units Receiver Adjustments L353 R547P501 L354 R360Blanker EXTNoise Main Band OFFCP851 L283L22 CP852Transmitter Adjustments R138 R503C659 R131GND If TotalMain Gain LO LeakCP1613 R504R202 R1613Software Adjustment Software Adjustment MeterNoise SQL Filter CalibrationTX Power HPF OFF DeviationLPF UX-910 Adjustments C332 CP321CP322 R13Power SET APCPre-setting for APC adjustment Front Unit Section Parts ListDisplay Board Resistor ERA3YED VR-A Board Func BoardVR-B Board MIC Board RIT BoardJack Board PLL UnitResistor ERA3YEB Thermistor Tantalum ECST1AD107R Main Unit REG BA09TDiode DAN222TL Resistor ERA3YKD R364 7030003320 R915 7030003520 Tantalum Temsva 1C 335M-8L Electrolytic ECEV1EA4R7SR Electrolytic Relay Diode HSU88TRF Coil Eljre 15NG-F Resistor ERJ1WYJ181U Resistor ERJ1TYJ102U JB 1H JB 1C Mica VARISTOR-B Board DRV BoardBARISTOR-A Board BARISTOR-C Board2UX-910MAIN Unit Main Unit UX-910Resistor RGB3L R15 Resister ERA3YED Tantalum ECST1CC226R CH 1H Connectot 25FMN-BTK Cover Parts Mechanical PartsDisplay Unit Chassis PartsUX-910 Main Unit UnpackingUX-910 Chassis Parts UX-910 UnpackingSEMI-CONDUCTOR Information Transistors and FET’SDTA114 EE TL Diodes MA29BSection Board Layouts Page Icom America Inc 13714HZ-C1

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.