AAO2101850Vehicle Mounted Family Radio Transmitter

1 OWNER’S MANUAL FRS RADIO 21-1850 INTRODUCTION Your Radio Shack remote control FRS Radio is a mobile type radio. Magnet –mounted antenna RF base can be mounted on the top of the car. It provides the best antenna efficiency than any hand-held type FRS transceiver. The remote control unit is linked with a cable and provides an easy to use in a comfortable environment. You can start using your FRS radio immediately without any license required! Your radio comes with 14 FRS channels and you can talk with another person who has a FRS radio and is on the same channel and privacy code that you are using. Your remote unit offers a multifunctional liquid crystal display with backlight, auto-squelch which eliminates noise between transmission, built-in modulation limiter circuit which automatically adjust the radio for a wide variety of voice levels to ensure a clear transmission, memory retention and keypad lock. USING THE RADIO A. DISPLAY The remote unit comes with a multifunctional backlight display. By pressing any button except the CALL and PTT, the backlight will illuminate for 7 seconds. The liquid crystal display has been enlarged to show all of the operating modes. 1. Shows the selected channel number. 2. Shows the selected quiet code number. 3. “ QUIET”: Displayed when the QUIET privacy mode is enabled. 4. “ ” : Displays when your radio is transmitting or the CALL button is pressed. 5. “ BUSY”: Displays when a call is being received. 6. “ ”: Displays when the keypad lock has been activated. 2 7. “SCAN”: Displays when the transceiver scans through all the channels. B. FUNCTION AND LOCATION OF THE CONTROLS 1. “ON/OFF” Volume Control In “OFF” position, your transceiver is off. Rotate this control clockwise to turn on your radio and adjust the volume, until you get a comfortable listening level. 2. LCD Display Your transceiver has a multifunctional liquid crystal display with backlight ( see “A” for detail). 3. CH ∆ ∆∆ ∆ Button Press CH ∆ ∆∆ ∆ to move one channel up. Release when you reach the desired channel. To Operate the Scan Press and hold CH ∆ ∆∆ ∆ or CH ∇ ∇∇ ∇ for two seconds allows the unit to begin scanning up or down through the channels. If a valid signal is present, the radio will stop on the active channel and remain stopped for 4 seconds. If no button is pressed, the scan mode will then immediately resume for the next channel after the signal disappears within 4 seconds or after 4 seconds have elapsed. If no signal is found on a channel, the unit will immediately continue to scan when no button is pressed. During scan, if CH ∆ ∆∆ ∆ or CH ∇ ∇∇ ∇ is pressed, the unit will exit scan mode and stop at the current displayed channel. In both cases, pressing PTT, CALL, and MON buttons will cause the scan to turn off and stop at the current displayed channel. Press QUIET button during scan to stop scan and return to the 3 original channel. 4. CH ∇ ∇∇ ∇ Button Press CH ∇ ∇∇ ∇ to move one channel down. Release when you reach the desired channel. 5. QUIET Button Press QUIET button to enable or disable the QUIET privacy mode operation. To determine QUIET privacy code setting, press and hold QUIET button for 2 seconds until QUIET icon is displayed and the quiet code indicator flashes. Press CH ∆ ∆∆ ∆ or CH ∇ ∇∇ ∇ to select the desired code between 01 and 38. Press QUIET button once to confirm and exit the setting mode and your radio is now in the privacy mode operation. Note: It is recommended to select the middle range of the QUIET privacy codes. If you have selected the front and end QUIET privacy codes, please wait 1 to 2 seconds to initiate QUIET, i.e. Press and hold Push-To-Talk button to transmit, wait 1 to 2 seconds, and then speak in a normal voice. 6. CALL Button You can cause a ringer sound on all radios tuned to the same FRS channel and/or the privacy code as your radio. To send a page, press and hold down the CALL button. At this time, the speaker rings a bell, and the transmit icon is displayed and the outer (( )) icon flashes. You can also lock your radio setting to avoid accidental pressing of keys by activating the keypad lock. Press and hold MON button, then press CALL button to activate or deactivate the keypad lock. To Operate Lock Operation Press and hold MON Button and press the CALL button to activate the key lock. The lock icon is displayed. 7. Push-To-Talk Button To talk, hold down Push-To-Talk . Speak into the microphone in a normal tone of voice when the transmit icon is displayed. When you finish speaking, release Push-To-Talk button. 8. MON Button Press this button to open the automatic squelch and allow background noise to be heard. Release MON button to turn the auto-squelch back on. 9. External Microphone/Speaker Jack Connect an optional speaker/microphone or earphone in this jack. 10. Antenna Provides excellent reception. 11. Power Supply Plug the cigarette lighter adapter into the car cigarette lighter jack. C. OPERATION 1. To set the privacy code, check the function instructions. 2. Rotate the ON/OFF volume control clockwise to turn the unit on. Press the “ MON ” button and adjust the volume for a normal listening level. 4 3. Select the desired channel and/or QUIET privacy code. 4. Press Push-To-Talk button to transmit or CALL button to cause a page. 5. To receive, simply release Push-To-Talk button. Note : You can only communicate with another radio that is using the same channel and/or the same QUIET privacy code as your radio. TECHNICAL SPECIFICATIONS Frequency Range................................................................................................462-467 MHz Channels..............................................................................................................................14 Power supply...........................................................................................................12-13.8V Sensitivity at 12dB Sinad................................................................................................0.5…

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From: Kenneth Nichols [[email protected]] Sent: Tuesday, August 01, 2000 2:16 PM To: [email protected] Cc: Bruce Franca; Julius Knapp; Rich Fabina; Raymond Laforge; [email protected]; [email protected] Subject: Re: FCC ID: AAO2101850 Dwayne, As I stated in my last email, we felt that the concept for a device as outlined below would comply with the integral antenna Rules. However, to ensure the WTB supported that decision, we requested their views. They have just replied and agree with the Laboratory that the concept for this device does comply with the integral antenna Rules. Thanks for your patience during our review. Ken Dwayne Campbell <[email protected]> 07/20/00 12:02PM >>> We just received communication from our manufacturer, Tekcom Industries, indicating that our FRS model 21-1850 (FCC ID AAO21-1850) manufactured for RadioShack was rejected by the Commission. We are concerned that the design of this product is being confused with a similar product that was properly rejected by the Commission in 1998. While we understand and support the Commissions decision to reject the prior product since it did not comply with the rules, we would like to make sure you understand the differences between the earlier non- compliant product and our current application, which we feel complies with the intent and letter of the rules. The prior non-compliant FRS radio permitted connection of an external antenna by disconnecting the original antenna and connecting a remote external antenna. The user connection permitted easy substitution of the supplied external antenna with a non-conforming high gain antenna, signal amplifier, or other device not permitted by the FRS rules. By contrast the 21-1850 is a FRS product configured for mobile use. It consists of a transmitter and all RF circuitry contained within a single housing. The antenna is integral to that housing; it can not be detached from the housing by the user. The control circuitry, display, speaker and microphone are contained a second housing that is permanently attached to the transmitter housing with a non-detachable cable (see attached block diagram). It is not possible for the user to replace, extend, or modify the cable between the microphone housing and the transmitter housing. By designing the unit in this way, we feel that this product complies with the strictest interpretation of the paragraph §95.647 which states: "FRS unit and R/C transmitter antenna. - The antenna of each FRS unit, and the antenna of each R/C station transmitting in the 72-76 MHz band, must be an integral part of the transmitter. The antenna must have no gain (as compared to a half-wave dipole) and must be vertically polarized." PAGE 2 and further clarification issued in the Memorandum Opinion and Order 98-293, paragraph 29 adopted October 30, 1998: "29. We agree with Motorola that as originally envisioned, FRS units would use relatively inefficient antennas that were integral, i.e. either permanently attached or designed into, the unit. We intended the term "integral" in this context to have its common meaning (i.e. essential for completion; whole; entire; intact). We also agree with Motorola that the plain language of Section 95.194© of the rules is clear and that approving units that are easily modified to allow other antennas or devices to be attached to the unit violates the rule and allows users of FRS units to defeat its purpose. Additionally, FRS units that include antennas that can be detached by unscrewing or unplugging the antenna from the unit allow the consumer to easily interconnect the FRS unit to an external antenna, power amplifier of other readily available apparatus. We note that consumer attached devices such as these are not type accepted with the FRS unit, and, therefore, can not be used with it." By designing the antenna integral to the transmitter and its housing, it is not possible for the user to connect the transmitter to non- conforming devices such as high gain antennas, signal amplifiers, or other devices not permitted by the FRS rules to extend the range or improve the performance of the FRS radio. Our intent for this product is to provide a form factor that is more convenient for mobile use and also to respond to consumer complaints that handheld units experience reduction in range when used inside a vehicle. This product continues to comply with the ERP limits in 95.639 which states: "No FRS unit, under any condition of modulation, shall exceed 0.500 W effective radiated power (ERP)." The range of this product is consistent with the range of a handheld FRS units operated under similar conditions when operated outside the vehicle. Based on this clarification, we request the Commission to reconsider their position regarding this application. We would like to discuss further with you by telephone to ensure that we have clearly explained the product configuration and that we fully understand the Commission's interpretation of the rules. Best Regards, Dwayne Campbell Senior Manager Regulatory Affairs and Engineering (817) 415-3203, Fax (817) 415-3092 RadioShack One Tandy Center 100 Throckmorton Suite 1300 Fort Worth, TX 76102 Paul Opitz Product Development Manager (817) 415-4976, Fax (817) 415-4976 RadioShack One Tandy Center 100 Throckmorton Suite 1433 Fort Worth, TX 76102 <<21-1850a.jpg>>

1 THEORY OF OPERATION 21-1850 This FRS transceiver provides accurate and stable operation. The basic functions consist of 8 main sections: • Power Supply Unit • Receiver Stage • Squelch Control • Transmit Stage • VCO and PLL • Micro-controller • CTCSS(QUIET) • CALL Power The power supply unit is a external cigarette lighter adapter. It can be plugged into the car cigarette plug. It regulates 12V~13.8V input to 8V with IC501 LM7808. The 8V power is spread into three sections. 1. The power for the RF-power amplifier. 2. The power for the Audio amplifier section. 3. 8V voltage is regulated to 3.5V by IC103 TK11335 for the VCO & PLL power, and also regulated to 3.5V by IC309 TK11335 for CPU power, TX and RX power control circuitry. Q304 and Q306 compose as a power switch for RX and TX. They are controlled by RX and TX CTL from CPU. Receive Stage RF signal is received through the antenna and is passed onto a low pass filter network and amplified by Q101. This allows only the required band signal to pass through to the band pass filter (BPF). The mixer Q103 converts the incoming signal down to 21.3MHz. This signal again passes to a 21.3MHz XTAL band pass filter F101. This gives a better channel selectivity. The selected 21.3MHz signal is amplified by IF amplifier Q104 before it is passed to the second converter IC101 TA31180FN. IC101 TA31180FN is the second converter with a 21.25MHz local oscillator. This converts the 21.3MHz signal down to 50KHz. This 50KHz signal is sent to discriminator. The detected audio signal passes through Audio Amplifier unit IC304 NJM3403, the 300Hz high pass filter and volume control, and then to the speaker. Squelch Control Squelch control circuitry consists of IC101 TA31180FN and its related circuit. The squelch signal output from IC101 pin 15 pass through filter amplifier circuit composed by pin 16 and pin 17. The signal is amplified and detected by IC101 and generate a control voltage at pin 19 of IC101 for CPU to detect. VR101 is used to control the threshold of the squelch (squelch sensitivity). Pin 19 of IC101 is output a Lo to MCU IC307 pin 15 to indicate an incoming signal is detected. Transmit Stage When the PTT switch goes down, the transceiver is switched into transmit mode through the TX/RX 2 exchange control. Q306 is turned on for the power to the transmitter. The voice is picked up by the condenser MIC and passes through the 300Hz high pass filter IC302 NJM3403 and is amplified by IC303 NJM3403 MIC amplifier circuit. The signal modulates with the carrier in the form of FM modulation. The modulated signal from the VCO goes into the power amplifier unit which consists of a buffer amplifier Q108A, a driver amplifier Q108B and the RF power amplifier Q106. The signal then is finally radiated out through antenna. VCO and PLL PLL circuitry is composed of IC102 M64082 the high frequency PLL and VCO. The channel information from the CPU is sent to the shift register in IC102 from pin 2. A control voltage is generated through the low pass filter to the VCO from pin 8 and is used to control RF frequency from Q113. Q114 is the RX/TX exchange switch. RF signal from the VCO passes through the buffer amplifier Q112 and then is fed into PLL IC102. In receive mode, the signal is fed to the receiver first mixer Q103 to convert the received signal to 21.3MHz. In transmit mode, this signal modulations with the audio signal and is passed through to the transmit power amplifier unit for transmission. Microcontroller The Microcontroller MPD789405 is the main control of the whole transceiver unit. It is also used to drive the LCD to show the status of the unit. On the LCD, there is current working channel display, transmit indication, receive indication, QUIET indication, and low battery indication. The MCU scans the keypad to detect key pressed and released, then execute the function accordingly. CTCSS(QUIET) The CTCSS consists of transmit and receive section. In CTCSS transmit, a CTCSS signal is added to the audio and modulated for transmission. CPU pin OUT1, OUT2, OUT3 and OUT4 output a 16 stage of digital values. These digital values then are passed through a digital to analog converter R385 to R392. The output is a step waveform, and then is filtered by a low pass filter and mixed with the audio. The receive section consists of a CTCSS decoder circuit which is used to separate the audio signal and a CTCSS signal for the existing of a CTCSS signal. The CTCSS signal is filtered and amplified by IC101 TA31180FN and reshaped as a square wave by IC305 NJM3403. The signal then is input to the CPU and is determined the CTCSS singal value for the valid CTCSS received. CALL When the CALL button is pressed, the transceiver is switched into transmit mode through the CPU control. IC306 MC14001 generates a ringer audio signal which is controlled by CPU. This 1.6KHz signal is amplified in the MIC amplifier unit and modulated for transmission. 3 ADJUSTMENT PROCEDURE STEPITEMADJUSTMENTPROCEDURE 1TX FrequencyVC101Adjust VC101 to obtain demanded TX frequency. 2TXL117 L118 L119 Adjust L117, L118, L119 to obtain demanded TX power. 3TX. Dev.VR3011. Inject an audio frequency (AF) -20dBm. 2. Adjust VR301 to obtain maximum TX deviation ≤ 2.5KHz. 3. Check MIC modulation sensitivity, and it should be 2.5~10mV. 4CTCSS Dev.Check CTCSS deviation if it is normal. 5RXCheck RX sensitivity if it is normal. 6RXL103 L104 Adjust L103 and L104 to obtain Max. Sensitivity. 7RXVR101Adjust VR101 to obtain demanded squelch sensitivity. ALIGNMENT PROCEDURES Important: The FCC requires that any frequency adjustment on a radiophone must be done by authorized 4 person, who is the holder of a current first or second class radiotelephone license. This unit has been fully aligned at the factory before shipment and does not normally require further adjustment. When necessary, however, the unit may be aligned as indicated below. Do not adjust any circuit in this radiotelephone unless you understand the circuit operation…

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Mr. Joe Dichoso Ref: FCC ID: AAO2101850; Radio Shack Correspondence Ref: #15939 Regarding the referenced inquiry: The referenced device is a FRS product configured for mobile use. It consists of a transmitter and all RF circuitry contained within a single housing. The antenna is integral to that housing; it can not be detached from the housing by the user. The control circuitry, display, speaker and microphone are contained in a second housing that is permanently attached to the transmitter housing with a non-detachable cable. It is not possible for the user to replace, extend or modi fy the cable between the microphone housing and the transmitter housing. By designing the unit in this way, we believe that this product complies with the strictest interpretation of Para. 95.647.

ADJUSTMENT PROCEDURE STEP ITEM ADJUSTMENT PROCEDURE 1TX Frequency VC101Adjust VC101 to obtain demanded TX frequency. 2TXL117 L118 L119 Adjust L117, L118, L119 to obtain demanded TX power. 3TX. Dev.VR3011. Inject an audio frequency (AF) -20dBm. 2. Adjust VR301 to obtain maximum TX deviation ≤ ≤≤ ≤ 2.5KHz. 3. Check MIC modulation sensitivity, and it should be 2. 5~10mV. 4CT CSS Dev.Check CT CSS deviation if it is normal. 5RXCheck RX sensitivit y if it is normal. 6RXL103 L104 Adjust L103 and L104 to obtain Max. Sensitivity. 7RXVR101Adjust VR101 to obtain demanded squelch sensit ivit y. ALIGNMENT PROCEDURES Important: The FCC requires that any frequency adjustment on a radiophone must be done by authorized person, who is the holder of a current first or second class radiotelephone license. This unit has been fully aligned at the factory before shipment and does not normally require further adjustment. When necessary, however, the unit may be aligned as indicated below. Do not adjust any circuit in this radiotelephone unless you understand the circuit operation and have experience in adjusting radiotelephone. Tampering with the radiotelephone may upset the alignment and lower its performance. Test Equipment Required The following equipment is required for the alignment. Regulated DC power supply, 0~12V,1A or higher; or 4.5V, 1A Audio signal generator,10Hz~3KHz Digital multimeter Deviation meter Frequency counter,0~500MHz high impedance Oscilloscope RF power meter, 0.5W High frequency standard generato,>500MHz Tracking generator,>500MHz Distortion analyzer Audio level meter T-coupler Alignment drivers, etc.

ENGINEERING STATEMENT For Type Certification of Radio Shack; a Division of Tandy Corporation Model No: 21-1850 FCC ID: AAO2101850 I am an Electronics Engineer, a principal in the firm of Hyak Laboratories, Inc., Springfield, Virginia. My education and experience are a matter of record with the Federal Communications Commission. Hyak Laboratories, Inc. has been authorized by Radio Shack; a Division of Tandy Corporation, to make type certification measurements on the 21-1850 transceiver. These tests made by me or under my supervision in our Springfield laboratory. Test data and documentation required by the FCC for Type Certification are included in this report. The data verifies that the above mentioned transceiver meets FCC requirements Type Certification is requested. ______________________________ Rowland S. Johnson Dated: June 16, 2000 A. INTRODUCTION The following data are submitted in connection with this request for type certification of the 21-1850 transceiver in accordance with Part 2, Subpart J of the FCC Rules. The 21-1850 is a mobile, UHF, frequency modulated transceiver intended for 12.5 kHz channel family radio service applications in the 462.5625-467.7125 MHz band. It operates from a 13.8 Vdc supply. Output power rating is 0.5 watts ERP. A permanently connected magnet-mount extra whip antenna is provided for mounting on a vehicle roof. A minimum of 1 meter separation exists between RF radiator and user. B. GENERAL INFORMATION REQUIRED FOR TYPE CERTIFICATION (Paragraph 2.983 of the Rules) 1. Name of applicant: Radio Shack, a Div. of Tandy Corp. 2. Identification of equipment: FCC ID: AAO2101850 a. The equipment identification label is a separate exhibit. b. Photographs of the equipment are included as a separate exhibit. 3. Quantity production is planned. 4. Technical description: a. 11k0F3E emission b. Frequency range: 462.5625 - 467.7125 MHz. c. Operating power of transmitter is fixed at the factory 0.5 W ERP. d. Maximum power permitted is 0.5 watts, and the 21- 1845 fully complied with that power limitation. e. The dc voltage and dc currents at final amplifier: Collector voltage: 7.9 Vdc Collector current: 0.19 mA f. Function of each active semiconductor device: See Appendix 1. g. Complete circuit diagram is submitted as a separate exhibit. h. A draft instruction book is submitted as a separate exhibit. i. The transmitter tune-up procedure is included as a separate exhibit. 2 B. GENERAL INFORMATION REQUIRED FOR TYPE CERTIFICATION (continued) j. A description of circuits for stabilizing frequency is included in the Theory of Operation. k. A description of circuits and devices employed for suppression of spurious radiation and for limiting modulation is included in the Theory of Operation. l. Not applicable. 5. Data for 2.985 through 2.997 follow this section. C. RF_Power_Output (Paragraph 2.985(a) of the Rules) The 21-1850 has a permanently attached antenna for external vehicle roof mounting without provisions for a coaxial connector. Therefore RF power output was calculated as shown in Table 1. (The transmitter was tuned by the factory.) TABLE 1 Operating Freq., MHz Power watts into a dipole antenna 462.5625 0.499 D. MODULATION CHARACTERISTICS 1. A curve showing frequency response of the transmitter is shown in Figure 1. Reference level was audio signal output from a Boonton 8220 modulation meter with one kHz deviation. Audio output was measured with a Audio Precision System One integrated test system. 2. Modulation limiting curves are shown in Figure 2, using a Boonton 8220 modulation meter. Signal level was established with a Audio Precision System One integrated test system. The curves show compliance with paragraphs 2.987(b). 3 D. MODULATION CHARACTERISTICS (continued) 3. Figure 3 is a graph of the post-limiter low pass filter which provides a roll-off of 60Logf/3 dB where f is audio frequency in kHz. Measurements were made following EIA RS-152B with an Audio Precision System One integrated test system on the Boonton 8220 modulation meter audio output. 4. Occupied_Bandwidth (Paragraphs 2.989(c) of the Rules) Figure 4 is a plot of the sideband envelope of the transmitter output taken with a Tektronix 494P spectrum analyzer. Modulation corresponded to conditions of 2.989(c)(1) and consisted of 2500 Hz tone at an input level 16 dB greater than that necessary to produce 50% modulation at 2373 Hz, the frequency of maximum response. Measured modulation under these conditions was 1.4 kHz. The plots are within FCC limits. The horizontal scale (frequency) is 10 kHz per division and the vertical scale (amplitude) is a logarithmic presentation equal to 10 dB per division. Unmodulated carrier reference is 0 dBm. E. SPURIOUS EMISSIONS AT THE ANTENNA TERMINALS (Paragraph 2.991 of the Rules) The 21-1850 has a permanently attached antenna. There is no connector for an external antenna. Therefore, no antenna terminal conducted measurements were made. F. DESCRIPTION OF RADIATED SPURIOUS MEASUREMENT FACILITIES A description of the Hyak Laboratories' radiation test facility is a matter of record with the FCC. The facility was accepted for radiation measurements from 25 to 1000 MHz on October 1, 1976 and is currently listed as an accepted site. 4 FIGURE 1 MODULATION FREQUENCY RESPONSE MODULATION FREQUENCY RESPONSE FCC ID: AAO2101850 FIGURE 1 5 FIGURE 2 AUDIO LIMITER CHARACTERISTICS AUDIO LIMITER CHARACTERISTICS FCC ID: AAO2101850 FIGURE 2 6 FIGURE 3 AUDIO LOW PASS FILTER RESPONSE AUDIO LOW PASS FILTER RESPONSE FCC ID: AAO2101850 FIGURE 3 7 FIGURE 4 OCCUPIED BANDWIDTH ATTENUATION IN dB BELOW MEAN OUTPUT POWER Required On any frequency more than 50% up to and including 100% of the 25 authorized bandwidth, 12.5 kHz (6.25-12.5 kHz) On any frequency more than 100%, up to and including 250% of the 35 authorized bandwidth (12.5-31.25 kHz) On any frequency removed from the assigned frequency by more 43+10LogP = 36 than 250% of the authorized (P = 0.499W) bandwidth (over 31.25 kHz) OCCUPIED BANDWI…

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