ARRL Laboratory Expanded Test-Result Report ICOM IC-746 Prepared by: American Radio Relay League, Inc. Technical Department Laboratory 225 Main St. Newington, CT 06111 Telephone: (860) 594-0214 Internet: [email protected] Order From: American Radio Relay League, Inc. Technical Department Secretary 225 Main St. Newington, CT 06111 Telephone: (860) 594-0278 Internet: [email protected] Price: $7.50 for ARRL Members, $12.50 for non-Members, postpaid. Model Information: IC-746 Serial #: 001674 QST "Product Review" September, 1998 Manufacturer: ICOM America 2380 116th Ave NE PO Box C-90029 Bellevue, WA 98004 Telephone: 425-454-8155 ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 1 List of Tests: (Page numbers are omitted because the length of the report varies from unit to unit.) Introduction Transmitter Tests: Transmit Output Power Transverter Jack Output Power Current Consumption Transmit Frequency Range Spectral Purity Transmit Two-Tone IMD Carrier and Sideband Suppression CW Keying Waveform Transmit Keyer Speed SSB/FM Transmit Delay Transmit/Receive Turnaround Transmit Composite Noise Receiver Tests: Noise Floor (Minimum Discernible Signal) Receive Frequency Range AM Sensitivity FM Sensitivity Blocking Dynamic Range Two-Tone, Third-Order Dynamic Range and Intercept Point Two-Tone, Second-Order Intercept Point In-Band Receiver IMD FM Adjacent Channel Selectivity FM Two-Tone, Third-Order IMD Dynamic Range Image Rejection IF Rejection Audio Output Power IF + Audio Frequency Response Squelch Sensitivity S-Meter Accuracy and Linearity In-Band Receiver IMD ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 2 Introduction: This document summarizes the extensive battery of tests performed by the ARRL Laboratory for each unit that is featured in QST "Product Review." For all tests, there is a discussion of the test and test method used in ARRL Laboratory testing. For most tests, critical conditions are listed to enable other engineers to duplicate our methods. For some of the tests, a block diagram of the test setup is included. The ARRL Laboratory has a document, the ARRL Laboratory Test Procedures Manual, that explains our specific test methods in detail, with a test description similar to the one in this report, a block diagram showing the specific equipment currently in use for each test, along with all equipment settings and a specific step by step procedure used in the ARRL Laboratory. While this is not available as a regular ARRL publication, the ARRL Technical Department Secretary can supply a copy at a cost of $20.00 for ARRL Members, $25.00 for non-Members, postpaid. Most of the tests used in ARRL product testing are derived from recognized standards and test methods. Other tests have been developed by the ARRL Lab. The ARRL Laboratory test equipment is calibrated annually, with traceability to National Institute of Standards and Technology (NIST). Most of the equipment is calibrated by a contracted calibration laboratory. Other equipment, especially the custom test fixtures, is calibrated by the ARRL Laboratory Engineers, using calibrated equipment and standard techniques. The units being tested are operated as specified by the equipment manufacturer. The ARRL screen room has an ac supply that is regulated to 117 or 234 volts. If possible, the equipment under test is operated from the ac supply. Mobile and portable equipment is operated at the voltage specified by the manufacturer, at 13.8 volts if not specified, or from a fully charged internal battery. Equipment that can be operated from 13.8 volts (nominal) is also tested for function, output power and frequency accuracy at the minimum specified voltage, or 11.5 volts if not specified. Units are tested at room temperature and humidity as determined by the ARRL HVAC system. Also, units that are capable of mobile or portable operation are tested at their rated temperature range, or at –10 to +60 degrees Celsius in a commercial temperature chamber. ARRL "Product Review" testing represents a sample of only one unit (although we sometimes obtain an extra sample or two for comparison purposes). This is not necessarily representative of all units of the same model number. It is not uncommon that some parameters will vary significantly from unit to unit. The ARRL Laboratory and Product Review editor work with manufacturers to resolve any deviation from specifications or other problems encountered in the review process. These problems are documented in the Product Review. Units used in "Product Review" testing are purchased off the shelf from major distributors. We take all necessary steps to ensure that we do not use units that have been specially selected by the manufacturer. When the review is complete, the unit is offered for sale in an open mail bid, announced regularly in QST . Related ARRL Publications and Products: The 1998 ARRL Handbook for Radio Amateurs has a chapter on test equipment and measurements. The book is available for $32.00 plus $6 shipping and handling. The Handbook is also now available in a convenient, easy to use CD-ROM format. In addition to the complete Handbook text and graphics, the CD-ROM includes a search engine, audio clips, zooming controls, bookmarks and clipboard support. The cost is $49.95 plus $4.00 shipping and handling. You can order both versions of the Handbook from our web page at http://www.arrl.org, or contact the ARRL Publications Sales Department at 888-277-289 (toll free). It is also widely stocked by radio and electronic dealers and a few large bookstores. The ARRL Technical Information Service has prepared an information package that discusses Product Review testing and the features of various types of equipment. Request the "What is the Best Rig To Buy" package from the ARRL Technical Department Secretary. The cost is $2.00 for ARRL Members, $4.00 for non-Members, postpaid. Many QST "Product Reviews" have been reprinted in three ARRL publications: The ARRL Radio Buyers Sourcebook (order #3452) covers selected Product Reviews from 1970 to 1990. The cost is $15.00 plus $4.00 shipping and handling. The ARRL Radio Buyers Sourcebook Volume II (order #4211) contains reprints of all of the Product Reviews from 1991 and 1992. The cost is $15.00 plus $4.00 shipping and handling. The VHF/UHF Radio Buyer’s Sourcebook (order #6184) contains nearly 100 reviews of transceivers, antennas, amplifiers and accessories for VHF and above. You can order these books from our Web page or contact the ARRL Publications Sales Department to order a copy. ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 3 QST is also available on CD ROM! The 1997 ARRL Periodicals CD ROM (order #6729), the 1996 ARRL Periodicals CD ROM (order #6109) and the 1995 ARRL Periodicals CD ROM (order #5579) each contain a complete copy of all articles from a year’s worth of QST, the National Contest Journal and QEX (ARRL's experimenter's magazine). Each CD is available for $19.95 plus $4.00 for shipping and handling. Contact the ARRL Publications Sales Department to order a copy. Older issues of QST are also available: QST View CD-ROMs come in sets covering either five years each (1990-1994, 1985- 1989, 1980-1984, 1975-1979, 1970-1974, 1965-1969 and 1960-1964) or ten years each (1950-1959, 1940-1949 and 1930-39). The price for each set is $39.95. Shipping and handling for all ARRL CD ROM products is $4.00 for the first one ordered, $1.00 for each additional set ordered at the same time. Additional test result reports are available for: Manufacturer Model Issue Alpha Power 91ß Sep 97 Ameritron AL-800H Sep 97 ICOM IC-706 Mar 96 IC-706 MkII Jan 98 IC-746 Sep 98 IC-756 May 97 IC-775DSP Jan 96 IC-821H Mar 97 JRC NRD-535 May 97 Kenwood TS-570D Jan 97 TS-870S Feb96 QRO HF-2500DX Sep 97 Ten-Tec Centaur Jun 97 Omni VI + Nov 97 Yaesu FT-847 Jul 98 FT-920 Oct 97 FT-1000MP Apr 96 The cost is $7.50 for ARRL Members, $12.50 for non-Members for each report, postpaid. ARRL Members can obtain any three reports for $20.00, postpaid. ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 4 Transmitter Output Power: Test description: One of the first things an amateur wants to know about a transmitter or transceiver is its RF output power. The ARRL Lab measures the CW output power for every band on which a transmitter can operate. The unit is tested across the entire amateur band and the worst-case number for each band is reported. The equipment is also tested on one or more bands for any other mode of operation for which the transmitter is capable. Typically, the most popular band of operation for each mode is selected. Thus, on an HF transmitter, the SSB tests are done on 75 meters for lower sideband, 20 meters for upper sideband, and AM tests are done on 75 meters, FM tests are done on 10 meters, etc. This test also compares the accuracy of the unit's internal output-power metering against the ARRL Laboratory's calibrated test equipment. The purpose of the Transmitter Output-Power Test is to measure the dc current consumption at the manufacturer's specified dc-supply voltage, if applicable, and the RF output power of the unit under test across each band in each of its available modes. A two-tone audio input, at a level within the manufacturer's microphone-input specifications, is used for the SSB mode. No modulation is used in the AM and FM modes. Many transmitters are derated from maximum output power on full-carrier AM and FM modes. In most cases, a 100-watt CW/SSB transmitter may be rated at 25 watts carrier power on AM. The radio may actually deliver 100 watts PEP in AM or FM but is not specified to deliver that power level for any period of time. In these cases, the published test-result table will list the AM or FM power as being "as specified." In almost all cases, the linearity of a transmitter decreases as output power increases. A transmitter rated at 100 watts PEP on single sideband may actually be able to deliver more power, but as the power is increased beyond the rated RF output power, adjacent channel splatter (IMD) usually increases dramatically. If the ARRL Lab determines that a transmitter is capable of delivering its rated PEP SSB output, the test-result table lists the power as being "as specified." Key Test Conditions: Termination: 50 ohms resistive, or as specified by the manufacturer. Block Diagram: AC ONLY CAUTION!: Power must only be applied to the attenuator input! Do not reverse input and output terminals of the Bird 8329. TWO-TONE RF Power AUDIO DUT RF WATTMETER Attenuator & GENERATOR TRANSMITTER 100 WATTS BIRD 4381 100 WATTS Dummy Load TYPICAL TYPICAL Bird 8329 PTT SWITCH TELEGRAPH KEY POWER SUPPLY DC ONLY ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 5 Transmitter Output Power Test Results: Frequency Mode Unit Measured Unit Measured Notes Band Minimum Minimum Maximum Maximum Power (W) Power (W) Power (W) Power (W) 1.8 MHz CW See note 1 1.6 W “100” 115 W 1, 2 3.5 MHz CW – 1.7 – 117 3.5 MHz AM – 1.5 – 42.8 W carrier 7.0 MHz CW – 1.8 – 117 10.1 MHz CW – 1.8 – 118 14 MHz CW – 1.8 – 118 14 MHz USB – 1.8 – 115 18 MHz CW – 1.8 – 117 21 MHz CW – 1.8 – 118 24 MHz CW – 1.8 – 116 28 MHz CW – 1.8 – 113 28 MHz FM – – – 110 50 MHz CW – 1.5 – 105 50 MHz FM – – – 102 50 MHz AM – – – 40.2 W carrier 50 MHz SSB – – – 104 144 MHz CW – 1.8 – 93 144 MHz FM – – – 94 144 MHz AM – – – 41.6 W carrier 144 MHz SSB – – – 93 Notes: 1. Unit's power meter consists of LED segments; minimum power showed 0 segments lit. 2. The unit showed LED segments reaching a fixed display label reading 100 at full power. 99. Temperature chamber tests and 11.5 volt tests are performed only for portable and mobile equipment. Current Consumption Test: (DC-powered units only) Test Description: Current consumption can be a important to the success of mobile and portable operation. While it is most important for QRP rigs, the ARRL Lab tests the current consumption of all equipment that can be operated from a battery or 12-14 vdc source. The equipment is tested in transmit at maximum output power. On receive, it is tested at maximum volume, with no input signal, using the receiver's broadband noise. Any display lights are turned on to maximum brightness, if applicable. This test is not performed on equipment that can be powered only from the ac mains. Current Consumption: Voltage Transmit Output Power Receive Current Lights? Notes Current 13.8 V 20 A 100.2 W 2.5 A ON ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 6 Transmit Frequency Range Test: Test Description: Many transmitters can transmit outside the amateur bands, either intentionally, to accommodate MARS operation, for example, or unintentionally as the result of the design and internal software. The ARRL Lab tests the transmit frequency range inside the screen room. The purpose of the Transmit Frequency Range Test is to determine the range of frequencies, including those outside amateur bands, for which the transmitter may be used. The key test conditions are to test it at rated power, using nominal supply voltages. Frequencies are as indicated on the transmitter frequency indicator or display. Most modern synthesized transmitters are capable of operation outside the ham bands. However, spectral purity is not always legal outside the hams bands, so caution must be used. In addition, most other radio services require that transmitting equipment be type accepted for that service. Amateur equipment is not legal for use on other than amateur and MARS frequencies. Test Results: Frequency Low-Frequency Limit High-Frequency Limit Notes 160 M 1.800.00 MHz 1.999 999 MHz 80 M 3.400.00 MHz 4.099 999 MHz 40 M 6.900.00 MHz 7.499 999 MHz 30 M 9.900.00 MHz 10.499 999 MHz 20 M 13.900.00 MHz 14.499 999 MHz 17 M 17.900.00 MHz 18.499 999 MHz 15 M 20.900.00 MHz 21.499 999 MHz 12 M 24.400.00 MHz 25.099 999 MHz 10 M 28.000.00 MHz 29.999 999 MHz 6 M 50.000.00 MHz 54.000 000 MHz 2 M 144.000.00 MHz 148.000 000 MHz CW Transmit Frequency Accuracy Test: Test Description: Most modern amateur equipment is surprisingly accurate in frequency. It is not uncommon to find equipment operating within a few Hz of the frequency indicated on the frequency display. However, some units, notably "analog" units, not using a phase-lock loop in the VFO design, can be off by a considerable amount. This test measures the output frequency. Unit is operated into a 50-ohm resistive load at nominal temperature and supply voltage. Frequency is also measured at minimum output power, low supply voltage (12 volt units only) and over the operating temperature range (mobile and portable units only). Non-portable equipment is not tested in the temperature chamber. Test Results: Unit Frequency Supply Temperature Measured Frequency Notes Voltage Full Output Power 14.000.00 MHz 13.8 V 25 C 14.000.027 MHz ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 7 Spectral Purity Test: Test Description: All transmitters emit some signals outside their assigned frequency or frequency range. These signals are known as spurious emissions or "spurs." Part 97 of the FCC rules and regulations specify the amount of spurious emissions that can be emitted by a transmitter operating in the Amateur Radio Service. The ARRL Laboratory uses a spectrum analyzer to measure the spurious emission on each band on which a transmitter can operate. The transmitter is tested across the band and the worst-case spectral purity on each band is captured from the spectrum analyzer and stored on disk. Spectral purity is reported in dBc, meaning dB relative to the transmitted carrier. The graphs and tables indicate the relative level of any spurious emissions from the transmitter. The lower that level, expressed in dB relative to the output carrier, the better the transmitter is. So a transmitter whose spurious emissions are -60 dBc is spectrally cleaner than is one whose spurious emissions are -30 dBc. FCC Part 97 regulations governing spectral purity are contained in 97.307 of the FCC rules. Information about all amateur rules and regulations is found in the ARRL FCC Rule Book. Additional information about the decibel is found in the ARRL Handbook. Key Test Conditions: Unit is operated at nominal supply voltage and temperature. Output power is adjusted to full power on each amateur band. A second measurement is taken at minimum power to ensure that the spectral output is still legal at low power. The level to the spectrum analyzer is - 10 dBm maximum. The resolution bandwidth of the spectrum analyzer is 10 kHz on HF, 100 kHz on VHF, MHz on UHF. Block Diagram: CAUTION!: Power must only be applied to the attenuator input! Do not reverse input and output terminals of the Bird 8329. TWO-TONE RF Power AUDIO DUT RF WATTMETER Attenuator & TRANSMITTER BIRD 4381 Dummy Load GENERATOR 100 WATTS 100 WATTS Bird 8329 TYPICAL TYPICAL TELEGRAPH KEY POWER SOURCE DO NOT 10 dB STEP 1 dB STEP EXCEED SPECTRUM 0 dBm ATTENUATOR ATTENUATOR ANALYZER HP 355D HP 3555C HP 8563E ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 8 Spectral-Purity Graphs: 0 0 Reference Level: 0 dBc Reference Level: 0 dBc –10 –10 –20 –20 –30 –30 –40 –40 –50 –50 –60 –60 –70 –70 –80 –80 0 5 10 15 20 25 30 35 40 45 50 0 5 10 15 20 25 30 35 40 45 50 Frequency (MHz) Frequency (MHz) ICOM IC-746 serial number 001674 ICOM IC-746 serial number 001674 1.8 MHz Band, Spectral Purity, 100 W 7.0 MHz Band, Spectral Purity, 100 W F:\SHARED\PROD_REV\TESTS\IC746\IC746SLO.TXT F:\SHARED\PROD_REV\TESTS\IC746\IC746S40.TXT 0 0 Reference Level: 0 dBc Reference Level: 0 dBc –10 –10 –20 –20 –30 –30 –40 –40 –50 –50 –60 –60 –70 –70 –80 –80 0 5 10 15 20 25 30 35 40 45 50 0 10 20 30 40 50 60 70 80 90 100 Frequency (MHz) Frequency (MHz) ICOM IC-746 serial number 001674 ICOM IC-746 serial number 001674 3.5 MHz Band, Spectral Purity, 100 W 10.1 MHz Band, Spectral Purity, 100 W F:\SHARED\PROD_REV\TESTS\IC746\IC746S80.TXT F:\SHARED\PROD_REV\TESTS\IC746\IC746S30.TXT ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. All Rights Reserved. Page 9 0 0 Reference Level: 0 dBc Reference Level: 0 dBc –10 –10 –20 –20 –30 –30 –40 –40 –50 –50 –60 –60 –70 –70 –80 –80 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100 Frequency (MHz) Frequency (MHz) ICOM IC-746 serial number 001674 ICOM IC-746 serial number 001674 14.0 MHz Band, Spectral Purity, 100 W 21.0 MHz Band, Spectral Purity, 100 W F:\SHARED\PROD_REV\TESTS\IC746\IC746S20.TXT F:\SHARED\PROD_REV\TESTS\IC746\IC746S15.TXT 0 0 Reference Level: 0 dBc Reference Level: 0 dBc –10 –10 –20 –20 –30 –30 –40 –40 –50 –50 –60 –60 –70 –70 –80 –80 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100 Frequency (MHz) Frequency (MHz) ICOM IC-746 serial number 001674 ICOM IC-746 serial number 001674 18.1 MHz Band, Spectral Purity, 100 W 24.9 MHz Band, Spectral Purity, 100 W F:\SHARED\PROD_REV\TESTS\IC746\IC746S17.TXT F:\SHARED\PROD_REV\TESTS\IC746\IC746S12.TXT ARRL Laboratory Expanded Test-Result Report Model: ICOM IC-746 Serial: 001674 Copyright 1998, American Radio Relay League, Inc. 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