MVZCRW-SWeather Radio Receiver

INSTRUCTION MANUAL MODEL CRW-S N.O.A.A. Weather receiver FCC ID: MVZCRW-S GORMAN-REDLICH 257 W. UNION ST. ATHENS, OH 45701 PHONE: (740) 593-3150 FAX: (740) 592-3898 http://www.gorman-redlich.com email: [email protected] FCC warning Warning: Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user authority to operate the equipment. FCC Compliance Statement This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) this device may not cause harmful interference, and (2 this device must accept any interference received including interference that may cause undesired operation. NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: • Reorient or relocate the receiving antenna • Increase the separation between the equipment and receiver • Connect the equipment into an outlet on a circuit different from that to which the receiver is needed • Consult the dealer or an experienced radio/TV technician for help WARRANTY For a period of 2 years from date of shipment, Gorman-Redlich will repair or replace, at its option, any Model CRW-S receiver that fails in normal service without a charge for parts or labor and with a flat $25 fee, prepaid by purchaser, to cover shipping and handling. Receivers can only be accepted for adjustment under Warranty following notification by letter, telephone or e-mail. Receivers showing evidence of modification or abuse, in the judgment of Gorman- Redlich, cannot be accepted for repair under Warranty, but will be repaired for a reasonable fee, with the consent of the purchaser. NOAA WEATHER RADIO The National Weather Service (NWS), a branch of the National Oceanic and Atmospheric Administration (NOAA), operates a network of stations broadcasting around-the –clock weather on seven frequencies, spaced at 25 KHz intervals from 162.4 MHz to 162.55 MHz. About 890 stations are in operation as of April 2004. Modulation is narrow-band FM, and polarization is vertical. In addition to local and national weather, other information tailored to the locality, such as soil conditions and marine information, is broadcast by NWS. If a severe storm, flood, or nuclear attack threatens, three bursts of coded FSK is followed by a 1050 Hz signal tone transmitted for ten seconds by NWS. The Model CRW-S will be demuted after 6 seconds of 1050 tone for automatic warning of impending danger. The FCC has authorized rebroadcast of NWS transmissions by commercial AM, FM and TV stations, provided: 1) rebroadcast must be within one hour of receipt, 2) commercials aired during rebroadcast must not convey an endorsement by the government, and 3) credit must be given to NWS. GENERAL DESCRIPTION OF MODEL CRW-S RECEIVER The RF section of the Model CRW-S is a double-conversion superheterodyne, with both oscillators crystal-controlled. First IF is 21.4 MHz and second IF is 455 KHz. Receive frequency can be selected to be any one of the seven NWS frequencies between 162.4 and 162.55. The passband of the receiver is controlled by a four-pole crystal filter at 21.4 MHz and a four-pole ceramic filter at 455 KHz to produce a response characteristic with a nearly ideal rectangular shape about +/- 15 KHz wide and sufficient skirt selectivity so that adjacent channels at +/- 25 MHz are attenuated about 70 db. The RF amplifier (Q1) and the first mixer (Q2) are dual-gate MOSFETS, having excellent cross-modulation rejection. The second mixer and the second local oscillator are part of U1. Most of the receiver gain takes place at 455 KHz in a limiting amplifier that is part of U1. U1 also contains a product detector for demodulation of the narrowband FM signal, and an operational amplifier that is used to shape the audio passband and to provide a low-impedance audio output. Audio pre-amplification and power amplification take place in U9, U10, U11. FRONT PANEL The front panel of the CRW-S weather receiver features, from the left: 1. Red alert LED labeled “ALERT” 2. To the right of the alert LED, a pushbutton switch labeled “MUTE-DEMUTE” 3. Yellow “RELAY CLOSED” LED 4. To the right of the relay LED, a pushbutton switch labeled “RELAY RESET” 5. Orange “REPLAY ALERT” LED 6. To the right of the replay LED, a pushbutton switch labeled “REPLAY ALERT” 7. Green Power-on LED 8. Volume control knob labeled “VOLUME 9. Speaker REAR PANEL The rear panel of the CRW-S weather receiver features: 1. A table with the DIP switch positions for tuning to each of the seven weather service frequencies 2. An external antenna connector. A female F connector 3. A plug to wire in a 12V external power supply 4. The receptacle for the 15V DC power supply 5. The 8 position DIP switch for selecting the receiver operating frequency and programming the radio for the location of installation. 6. A ten terminal removable plug 7. A eight terminal removable plug 8. A P.C. port for down loading the programming to the CRW-S 9. An auxiliary port to connect external equipment to the CRW-S such as a sign board. The positions on the 10 terminal strip, starting from the left end are: 1:2 A balanced 600 ohm continuous AUDIO OUT 3:4 A balanced 600 ohm AUDIO OUT that is gated on when the CRW-S detects incoming 1050 Hz to…

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Gorman-Redlich 257 West Union Street Athens, Ohio 45701 Fax:(740)592-3898 PH: (740)593-3150 Number of pages including this cover letter 1 To: Smith Electronics. From: James Gorman Date: March 1, 2004 Subject: Authorized letter "I, sole proprietor of Gorman-Redlich Manufacturing Company, do hereby authorize Smith Electronics, Inc. Electromagnetic Compatibility Laboratories to act on my behalf in front of the Federal Communications Commission with respect to all matters relating to certification of equipment under Part 15 of the FCC rules until further notice." I further certify that no party (as defined in §1.2002 (b) of CFR 47, 1992) to this application, including myself, is subject to a denial of federal benefits, that includes FCC benefits, pursuant to Section 5301 of the Anti-Drug Abuse Act of 1988, 21 U.S.C., 853(a) Dated this 1 day of March, 2004 James T. Gorman Printed Title: Owner

James R. Pollock SMITH ELECTRONICS, INC. ELECTROMAGNETIC COMPATIBILITY LABORATORIES Radio Frequency Interference Report on the Gorman-Redlich Weather Radio Receiver Model CRW-S May 20, 2004 Prepared by: Prepared for:Gorman-Redlich 257 Union Street Athens, OH 45701 Smith Electronics, Inc. 8200 Snowville Road Brecksville, OH 44141 Phone: (440) 526-4386 Fax: (440) 526-9205 TEST REPORT OBJECTIVE Measurements were performed on May 14 & 18, 2004, to determine if the Gorman-Redlich CRW-S weather receiver was in compliance with the FCC emissions requirements of 15.107, 15.109 and 15.111 for a digital device and a receiver. SUMMARY The Gorman-Redlich CRW-S weather receiver was found to be in compliance with the conducted and radiated radio frequency emissions requirement of the FCC for a digital device and a receiver. The CRW-S would be considered a Class A digital device but was found to meet the more stringent Class B requirements which are the same requirements as for the receiver. GENERAL INFORMATION MANUFACTURERGorman-Redlich 257 Union Street Athens, OH 45701 TEST DATESMay 14 & 18, 2004 EQUIPMENT UNDER TESTModel CRW-S Weather Radio Receiver FCC ID: MVZCRW-S SPECIFICATIONFCC Part 15 15.107(a); 15.109(a)(b), 15.111(a) INTRODUCTION The Gorman-Redlich CRW-S receiver is a receiver capable of tuning the seven weather band channels. Tuning is performed by setting DIP-switches on the back panel of the receiver. With a rack-mount design, it would probably be installed in a radio-room or equipment room rather than in an office location. Back panel connectors do provide for remote audio outputs, a flashing LED, remote relay closure and reset, and remote replay and mute/de-mute. Digital I/O ports are also provided for receiver programming and outputting a digital signal to a message board. A 15 VDC wall power pack, or a stand-by battery source generally powers the receiver. The antenna port is a standard “F” connector. The CWR-S also contains the digital circuitry necessary for proper operation and digital signal processing, and is thus a Class A digital device as well as a receiver The receiver is to tune between 162.40 MHz and 162.55 MHz and is a dual- conversion receiver with a first IF frequency of 21.4 MHz and a second IF of 455 kHz. The local oscillator (LO) of the system operates 21.4 MHz below the tuned frequency. This report describes the tests performed on the receiver in support of an application for certification. MEASUREMENTS PERFORMED The AC line input to the 15 VDC power pack was examined for conducted RF emissions with the receiver powered. The antenna input port was examined for any spurious emissions that might feed back from the receiver into the antenna system. The receiver chassis, with its external wiring and cabling was examined for spurious emissions that might be radiated from the chassis or its external connections. All measurements were taken following the procedures outlined in ANSI C63.4- 1992, with the results being compared to limits provided in sections 15.107(a), 15.109(a)(b) and 15.111(a) of the FCC Rules. All measurements were made with the receiver tuned to the middle of the weather band at 162.475 MHz. Photographs of the test set-ups are found in the Pictorials. The receiver as examined has been determined to comply with these sections and the data determining compliance is presented in this report. . LINE CONDUCTED EMISSIONS Conducted emissions were measured at the 50 Ohm termination points of the LISN with the receiver’s power pack plugged directly into the LISN AC output. The receiver was placed on a non-conducting table in the shielded room. The receiver was positioned 0.4 m from the room wall, which served as the ground plane. It was at least 0.8 m from other conducting planes. The detected emissions were recorded on a plotter from the spectrum analyzer. The FCC Class B limit of 250 uV or 48 dBuV is drawn on the plots for comparison. Figure 1 shows the conducted emissions detected at the LISN from the receiver between 450 kHz and 3 MHz. The upper plot, using peak detection, shows broadband emissions near the limit at 450 kHz. The lower plot of Fig. 1 covers the range from 400 kHz – 1.4 MHz using the quasi-peak detector and shows that the emissions are about 4 dB below the limit. The emissions data between 3 MHz and 30 MHz is found in Fig. 2. This also is peak data. Data for both hot and neutral sides of the line are overlaid on each plot. In viewing the plots of Figs. 1 & 2, it appears that the line conducted emissions are comfortably below the Class B limit for receivers. ANTENNA POWER CONDUCTION EMISSIONS Emissions from the antenna port of a receiver are required to be 2 nW or less if the antenna is not defined. Two nanowatts is equivalent to –57 dBm. The antenna port of the weather receiver was attached to the spectrum analyzer input port with a 0.5 meter length of RG-58. The loss in this length of cable ranges from less than 0.1 dB at 100 MHz to less than 0.2 dB at 1 GHz. The emissions over the frequency range of 0 to 1 GHz were measured in one analyzer scan which is seen in Fig. 3. The –57 dB level is shown on the scan. The four highest antenna port emissions are seen in Table 1. All other antenna emissions were more than 10 dB below the limit. Table 1 Antenna Conducted Power Levels FrequencyConducted PowerdB from Limit 141.1 MHz-62.5 dBm-5.5 160.0 MHz-66.2 dBm-9.2 282.1 MHz-62.6 dBm-5.6 705.4 MHz-66.3 dBm-9.3 RADIATED EMISSIONS The radiated emissions from the receiver were initially examined in the shielded room. The absence of RF noise in the shielded room allows for easy measurement of the emissions generated by the system. Measurements performed in the shielded room have unwanted perturbations caused by reflections and resonances. However, shielded room measurements are useful in determining the emissions profile, as well as identifying specific frequencies of interest for investigation on the open field site. All radiated emissions measured in the shie…

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Front View Rear View (Moved away from wall for visibility) Pictorial 1 Conducted Emissions CRW-S Weather Radio Test Set-Up Front View Rear View Pictorial 2 Radiated Emissions CRW-S Weather Radio Test Set-Up