AIERIT17-442UHF FM Transmitter

DTX-442 PROGRAMABLE VHF FM TRANSCEIVER MODULE OPERATING AND SERVICE MANUAL RITRON INC. 0 TABLE OF CONTENTS SECTION TOPIC PAGE 1. INTRODUCTION General Model Identification FCC REGULATIONS Licensing 5 Exposure to Radio Frequency Energy DTX-442 SPECIFICATIONS GENERAL RECEIVER 3 TRANSMITTER 3 DESCRIPTION OF INPUT/OUTPUT OPERATION MAINTENANCE INFORMATION 5 Surface Mount Repairs 5 Precautions for handling CMOS 6 Synthesizer shield 6 6. PROGRAMMING THE RADIO 9 PROGRAMMING THE RADIO USING A PC COMPUTER 9 Programmable Features 9 COMPUTER SOFTWARE COPYRIGHTS 9 7. DTX-442 THEORY OF OPERATION INTRODUCTION 10 POWER SUPPLY AND VOLTAGE DISTRIBUTION 10 REFERENCE OSCILLATOR 10 SYNTHESIZER 11 RECEIVER 11 Receiver Front End 11 FM Receiver Subsystem 11 Voice and Tone Conditioning 12 TRANSMITTER 12 Voice and Tone Conditioning in Transmitter 12 MICROCONTROLLER 14 8. DTX-442 ALIGNMENT PROCEDURE RECOMMENDED TEST EQUIPMENT 14 RADIO PREPARATION 14 REFERENCE FREQUENCY AND TRANSMITTER POWER 14 TRANSMITTER VOICE AND DATA DEVIATION 15 RECEIVER FRONT END TUNNING 15 RECEIVER SQUELCH 15 1 INTRODUCTION 1 General RITRON's DTX-442 transceiver module is designed to operate in the UHF band from 450 to 470 MHz. The transceiver is a single board unit with a 50 ohm BNC or SMA RF connector and a DB-15 connector providing input/output control. The unit supports voice through a microphone input and a nominal 1 watt speaker output. It supports up to 9600 bps 4-level FSK through its auxiliary in and auxiliary out ports. Each radio can be dealer or factory programmed to contain a unique set of eight operating frequencies and options. When all three channel select inputs are tied to ground the radio operates on channel 1. The channel selection is done in a binary manner on the CS2, CS1 and CS0 inputs. Separate RX and TX Quiet Call (CTCSS) or Digital Quiet call (DCS) tones can be programmed per channel. Transmitter wide or narrow deviation can be programmed on a per channel basis. The unit is set up to transmit 2 or 5 watts when operating at 13.8 VDC. The standby current at 13.8 VDC is 20 mA or less. Model Identification The standard DTX-442 is contained in an aluminum case with a BNC and DB-15. A standalone board version is also available. The DTX-442 model, serial number and FCC Identification are displayed on a label located on the top of the radio VCO shield for board versions or on the non- connector end for cased units. The following breakdown explains the model number. The model number form is: “ DTX-442-OABC ” Where: A is the connector type: B = BNC S = SMA 0 = no connector B designates the IF bandwidth: N = Narrow W = Wide C designates the case: D = deletion of case No designator = case present Examples: DTX-442-OBN 450 to 470 MHz narrowband receiver in case with BNC connector DTX-442-OSWD 450 to 470 MHz wideband receiver with SMA connector and no case Units without case are delivered with a vertical female DB15 connector. 2 FCC REGULATIONS Licensing The FCC requires the radio owner to obtain a station license for his radios before using them to transmit, but does not require an operating license or permit. The station licensee is responsible for ensuring that transmitter power; frequency and deviation are within the limits specified by the station license. The station licensee is also responsible for proper operation and maintenance of the radio equipment. This includes checking the transmitter frequency and deviation periodically, using appropriate methods. Exposure to Radio Frequency Energy: The DTX-442 transceiver consists of a transmitter and a receiver. The transmitter is active when the Push-to-Talk line is connected to ground or when activated electronically and emits radio frequency (RF) energy at a power level up to 5.0 watts. This product has been evaluated for compliance with the maximum permissible exposure limits for RF energy at the maximum power rating of the unit with the whip antenna available from RITRON. To ensure compliance with the Occupational/Controlled Exposure maximum limits, all persons must be at least 20 cm (7.9 inches) from the antenna while the unit is transmitting. Other antennas may require lesser or greater distances to meet the limits depending upon their gains relative to that tested. Higher gain antennas are capable of yielding a higher RF energy density in the strongest part of their field and would, therefore, require a greater separation from the antenna. The antenna tested for this product for RF exposure was the RITRON RAM-1545 with the included 25 feet of coaxial cable. This is the only antenna available from RITRON for use with this product. Other antennas may require lesser or greater distances to meet the limits depending upon their gains relative to that tested. Higher gain antennas are capable of yielding a higher RF energy density in the strongest part of their field and would, therefore, require a greater separation from the antenna. If other antennas are used, it is incumbent upon the installer to insure that the RF exposure limits for General Population/Uncontrolled Exposure are met. See 47CFR1.1307(b)(1)-(3) and/ or OET Bulletin 55, Edition 97-01 for more information on RF exposure guidelines. FCC Label: An FCC label must be visible on the unit as installed in its final configuration. If the unit is to be used as shipped from RITRON, this would be no problem since an FCC label is affixed to the top of the VCO shield. If the DTX- 442 is to be installed in an enclosure, the installer must ensure that either the FCC label on the unit is visible through a door, window or other opening, or add a label to the outside of the enclosure. If a label is to be added to the outside of the enclosure, the label must be of a type which is not easily removed or damaged and contain wording: Contains FCC ID: AIERIT17-442. 3 DTX-442 SPECIFICATIONS GENERAL FCC ID: AIERIT17-442 FCC Rule Parts: 90 Frequency Range: 450 to 470 MHz RF Channels: 8 Independent TX/RX frequencies Transmit/Receive bandwid…

Text truncated - open the document above for the full version.

TYPE OF EXHIBIT: MANUFACTURER’S STATEMENT FCC PART: 2.947 MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 11, 2003 PRODUCT STATEMENT: The RITRON model DTX-442 is a two-way transceiver module capable of supporting voice or data communications. It can operate either in narrowband mode 11K2F3E or wideband mode 16K0F3E. In narrowband mode it is also capable of supporting data rates up to 9600 bps (11K2F1D). Power output can be adjusted from 1 to 5 watts. A DTX-442 will cover the frequency range of 450 to 470 MHz. This product will be manufactured and marketed on a continuing basis in the United States by the applicant, RITRON, Inc. of Carmel, IN. TYPE OF EXHIBIT: STATEMENT OF CERTIFYING ENGINEER FCC PART: 2.947 MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 11, 2003 STATEMENT: I, Dennis Zimmerman, am now, and have been for the past 6 years a project engineer at RITRON, Inc. I have been employed in the two-way radio business for the past 18 years. I received a BSEE degree from the University of Cincinnati in 1977. I hereby certify that all the measurements were taken by me, or under my direct supervision and that they were taken using accepted engineering principles and accurately reflect the performance of the unit tested. Further, I attest that manufacturing controls exist such that this data are representative of units which will be manufactured by RITRON. Dennis Zimmerman Project Engineer RITRON, Inc. TYPE OF EXHIBIT: STATEMENT CONCERNING SPECTRUM EFFICIENCY FCC PART: 2.947 MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 11, 2003 STATEMENT: I, Dennis Zimmerman, certify that this product, DTX-442, meets the spectrum efficiency standard of one voice or 9600 bps of data per 12.5 kHz of channel bandwidth. Dennis Zimmerman Project Engineer RITRON, Inc.

RITRON, Inc. 505 West Carmel Dr. Carmel, IN 46032 Timco Engineering, Inc. December 30, 2003 Re:Modular Approval for AIERIT17-442 To Whom It May Concern: Ritron is seeking a modular approval for a UHF FM Transceiver covered under Part 90 of the FCC rules, FCC ID: AIERIT17-442. Although the 2000 Public Notice from the FCC concerning modular approval addresses Part 15 devices, we believe that the basic concerns addressed in that notice are applicable to this device. Specifically, 1. “The modular transmitter must have its own shielding.” This device has a shield over the transmitting and radiating circuitry. 2. “The modular transmitter must have buffered modulation/data inputs...” All of the modulation lines are internal to the one PC board used in this device and are buffered by operational amplifiers. No external signal of arbitrary amplitude and frequency can cause the occupied bandwidth and transmitter spurious emissions limits to be exceeded. 3. “The modular transmitter must have its own power supply regulation.” The power supply input voltage passes through at least one stage of power supply regulation and/or limiting before being impressed upon the transmitter stages. 4. “The modular transmitter must comply with the antenna requirements of Section 15.203 and 15.204(c).” This requirement is not applicable since we are requesting a Part 90 rather than a Part 15 approval. Specific antenna requirements do not exist under Part 90 rules. 5. “The modular transmitter must be tested for electromagnetic compatibility in a stand-alone configuration...” This product was tested without any external shielding other than that provided by the shields on the module itself. 6. “The modular transmitter must be labeled with its own FCC ID number...” The FCC ID label is on the module itself and is easily visible. For those applications where the module may be placed inside another enclosure, specific instructions are included in the Users Manual on the labeling requirements of the enclosure. 7. “The modular transmitter must comply with any specific rule or operating requirements applicable to the transmitter...” Specific operating requirements are covered in the Users Manual. 8. “The modular transmitter must comply with any applicable RF exposure requirements.” RF exposure measurements were taken for this device in the modular configuration without any other enclosure. I trust that Timco will agree that this product meets the requirements for a modular transmitter approval. Sam L. Dulaney Chief Engineer Ritron, Inc.

TYPE OF EXHIBIT: PHOTOGRAPHS FCC PART: 2.1033 c(12) MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 11, 2003 DTX-442 top side with shields DTX-442 top side with no shie lds DTX-442 bottom side

TYPE OF EXHIBIT: FCC ID LABEL FCC PART: 2.1033 MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 10, 2003 Description: The FCC ID label will be printed on a .75 x .75 inch non-smearing label. Labels will be numbered sequentially, with an initial 5-digit number of A1234. Records are maintained to track the next available serial number. All DTX-442 models share the same serial sequence. The FCC label attaches to the VCO shield as seen in photograph. Sample: Model: DTX-442-XXXX SN: A1234 RITRON INC. CARMEL IN. 46032 1-800-USA-1-USA FCCID:AIERIT17-442 FCC Label DTX-442 FCC Label location

TYPE OF EXHIBIT: PHOTOGRAPHS FCC PART: 2.1033 c(12) MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 11, 2003 DTX-442 top side with shields DTX-442 top side with no shie lds DTX-442 bottom side

TYPE OF EXHIBIT: OPERATIONAL DESCRIPTION FCC PART: 2.1033 (c)(4), (5), (7), (8), (10) MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 11, 2003 DESCRIPTION: The DTX-442 is a board level UHF FM RF transceiver module which operates at a maximum output power of five watts. It covers the frequency band of 450 to 470 MHz. The unit will support either 12.5 kHz or 25 kHz channel bandwidth operation for voice operation and/or 12.5 kHz channel bandwidth operation for data. The unit is designed to be operated in mobile service with an external source of DC power and an external antenna. TYPES OF EMISSIONS: For voice: 10K6F3E and 15K2F3E For data: 9K4F1D FREQUENCY RANGE: 450 to 470 MHz RANGE OF OPERATING POWER: 1.0 to 5.0 watts MAXIMUM POWER RATING: 5.0 watts TYPE OF EXHIBIT: OPERATIONAL DESCRIPTION FCC PART: 2.1033 (c)(4), (5), (7), (8), (10) MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 11, 2003 FINAL AMPLIFYING STAGE VOLTAGES AND CURRENTS: The following currents and voltage exist in the final RF power transistor with 13.8 VDC applied to the radio. The power is set by adjusting R222. Transmit Gate Drain Transmit Q208 Power Voltage Voltage Current Efficiency (watts) (volts) (volts) (Amps) (%) 1 1.0 13.6 0.28 26.3 2 1.2 13.5 0.40 37.1 3 1.4 13.4 0.52 43.1 4 1.5 13.3 0.64 47.1 5 1.8 13.2 0.76 50.0 CIRCUIT DESCRIPTION-STABILIZING FREQUENCY: The basic frequency stability of the unit is determined by the stability of the VCTCXO (voltage- controlled temperature compensated crystal oscillator), Y301, and the voltage which drives the modulation port of the VCTCXO. The VCTCXO is a monolithic device purchased by RITRON and specified to have a frequency stability in excess of that required by the Commission. Sampling of units by RITRON has confirmed that the devices do indeed meet the required stability. The voltage to the modulation port of the VCTCXO is maintained by a high stability voltage regulator. The variation in frequency caused by modulation port voltage variations is at least an order of magnitude below that of the basic VCTCXO. TYPE OF EXHIBIT: OPERATIONAL DESCRIPTION FCC PART: 2.1033 (c)(4), (5), (7), (8), (10) MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 11, 2003 CIRCUIT DESCRIPTION-SPURIOUS RADIATION SUPPRESSION: Spurious radiation caused by modulation components is limited by the modulation limiter filter. The modulation limiter filter is an active lowpass filter formed around two operational amplifier sections. This active filter has five poles with no transmission zeros. Harmonics of the transmitter carrier are suppressed by a 5-pole filter which follows the final transmitter stage matching network. This filter has less than 0.7 dB insertion loss and greater than 35 dB of ultimate rejection in the stopband. CIRCUIT DESCRIPTION-MODULATION LIMITING: Modulation limiting occurs by allowing the audio signal to be amplified enough to clip against an operational amplifier’s power supply rails and ground. The clipped signal is then sent to the limiter filter described above. In this product, IC305A and IC308A act as the modulation limiters. CIRCUIT DESCRIPTION-POWER LIMITING: The RF output power is limited by a closed loop power control which measures the current drawn by the final RF power device and adjust the drive level as appropriate to maintain a set current. The set point can be adjusted during alignment for output power levels between one and five watts.

TYPE OF TEST: ACTIVE COMPONENT LIST MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 12, 2003 SEMICONDUCTORS: The following pages contain a list of the semiconductors used in the DTX-442. Ref DesRitron# Device #Description CR101 48DB0003 BA782S DIODE CR201 48DB0003 BA782S DIODE CR401 48CB0001 BB149 DIODE CR402 48CB0001 BB149 DIODE CR405 48CB0001 BB149 DIODE D301 48A1005C MMBD7000 TRANSISTOR, DUAL DIODE CATH/ANODE D302 48A1005C MMBD7000 TRANSISTOR, DUAL DIODE CATH/ANODE D303 48A1005C MMBD7000 TRANSISTOR, DUAL DIODE CATH/ANODE D304 48A1005C MMBD7000 TRANSISTOR, DUAL DIODE CATH/ANODE D601 48BA0831 1SMA5913 DIODE D602 48E00B14 MBRS140T3 SCHOTTKY POWER RECTIFIER Q101 482100W2 PBR-951 TRANSISTOR, LOW PWR RF, UHF WIDEBAND Q102 482100V0 PBR-941 TRANSISTOR, LOW PWR RF, UHF WIDEBAND Q103 48210E2P BFS17A TRANSISTOR Q104 4821003B MMBT918LT1 TRANSISTOR,VHF NPN Q106 4841006U MMBFJ309L TRANSISTOR, RF NFET Q107 4801002A MMBT3906L TRANSISTOR, PNP SMD Q108 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q110 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q201 480100DH BCW68GLT1 TRANSISTOR, PNP GENERAL PURPOSE Q202 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q203 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q204 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q205 480100DH BCW68GLT1 TRANSISTOR, PNP GENERAL PURPOSE Q206 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q208 487A0002 PD54003 FET, RF PWR Q209 48280002 BFG35 TRANSISTOR, WIDE BAND Q210 482100W2 PBR-951 TRANSISTOR, LOW PWR RF, UHF WIDEBAND Q211 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q302 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q303 48010A6A MMUN21111 TRANSISTOR, DIGITAL PNP SMD Q305 48010A6A MMUN21111 TRANSISTOR, DIGITAL PNP SMD Q306 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q307 48010A6A MMUN21111 TRANSISTOR, DIGITAL PNP SMD Q309 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q310 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q311 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q312 480100DH BCW68GLT1 TRANSISTOR, PNP GENERAL PURPOSE Q315 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q316 48010A6A MMUN21111 TRANSISTOR, DIGITAL PNP SMD Q401 4841006T MMBF-J310TI TRANSISTOR, GP NFET Q402 482100V0 PBR-941 TRANSISTOR, LOW PWR RF, UHF WIDEBAND Q405 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q407 482100V0 PBR-941 TRANSISTOR, LOW PWR RF, UHF WIDEBAND Q408 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q409 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q410 48010A8A MMUN2211T1 TRANSISTOR, NPN SMD Q411 48010A6A MMUN21111 TRANSISTOR, DIGITAL PNP SMD Q601 48180007 MJD210 TRANSISTOR Q602 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q603 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q604 4801001Q MMBT5088 TRANSISTOR, NPN SMD Q605 484100P3 MMBF0202PLT1 POWER MOSFET 300 mAMPS, 20 VOLTS P-CHANNEL Q606 48010A6D MMUN2114 TRANSISTOR, DIGITAL PNP SMD U101 31030006 TA31136FN FM IF DETECTOR U104 31010018 LMV393 INTEGRATED CIRCUIT U201 31010008 LMT2904D I.C. DUAL OP AMP U301 314L0002 ATmega8 I.C. MICROCONTROLLER U303 31140002 74V1G14 SINGLE SCHMITT INVERTER U304 310K0004 LMV324MT I.C. QUAD OP AMP U305 310K0004 LMV324MT I.C. QUAD OP AMP U306 3131009 LM386N-3 IC, AUDIO PWR AMP U307 31010008 LMT2904D I.C. DUAL OP AMP U308 310K0004 LMV324MT I.C. QUAD OP AMP U309 31010020 LM321 LOW POWER SINGLE OP AMP U310 3.11E+03 MAX4544 I.C. ANALOG SWITCH SPDT U401 313K0006 LMX2306TM INTEGRATED CIRCUIT U402 31040004 TPS76301DBVR I.C. VOLTAGE REGULATOR U601 310M0001 LM3485 HYSTERETIC PFET BUCK CONTROLLER U602 31040003 TPS76050DBVR I.C. VOLTAGE REGULATOR

TYPE OF EXHIBIT: TUNE UP PROCEDURE FCC PART: 2.10333 (c9) MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Dec 18, 2003 DTX-442 ALIGNMENT PROCEDURE An authorized RF service technician must perform test and alignment of the DTX-442. Do not attempt service of the DTX-442 if not completely familiar with frequency synthesized radio operation. RECOMMENDED TEST EQUIPMENT 1) 0 to +15 VDC, 1A current-limited power supply 3) Oscilloscope 2) RF Communications Test with: 4) VTVM or DMM - FM Deviation Meter - RF Wattmeter 5) RITRON PC Programming Kit - Frequency Counter - SINAD Measuring Device RADIO PREPARATION 1) Remove the DTX-442 from case. 2) Connect the FM communications test set to the antenna connector. 3) Connect RITRON programming cable to radio and PC. 4) Apply 13.8 VDC to the red wire with the black to ground. 5) Run RITRON software and read the radio. 6) Program two channels for band edge tune up, one on the low side of the operating band and one on the high side and another in the middle. (Hint: use a bit of an offset from even frequencies to avoid receiver interference. A good choice is 450.1, 460.1 and 470.1. All of these will be wideband mode. 7) Type in these RX and TX frequencies in three channels. 8) Program the radio with these parameters. REFERENCE FREQUENCY AND TX POWER The DTX-442 is preset at the factory for 5 watts in high power and 2 watts in low power at 13.8 VDC. If you need to change or readjust do the following: 1) Make sure that the unit is at room temperature and power supply at 13.8 VDC. 2) Set the RF communications test set to the transmit mode. 3) Select low edge channel on channel select inputs CS2, CS1 and CS0. 4) Make sure the Hi/low power pin 5 is ungrounded. This selects high power. 5) Ground PTT pin 14 of J301 to transmit. 6) Transmitter frequency error should be less than +/-200 Hz ( assuming your equipment is calibrated) 7) Adjust the trimmer cap on the rectangular reference frequency oscillator Y301 if not within specs. 8) Adjust the power pot R222 to give 4.8 watts (+/- 0.2) 9) Confirm the upper edge frequency produces the same results. 10) If upper edge power is too low spike L208 to reduce inductance and increase high side power. To access L208 remove the copper tape over the access hole on the transmitter shield. The 2 turn inductor will appear beneath this opening. If the high side power is too high squeeze the 2 turn windings closer together to increase the inductance. 11) Check low edge power again. Readjust L201 to balance band edge powers. Replace copper tape over hole. TRANSMITTER VOICE & DATA DEVIATION If the transmitter voice deviation needs adjustment perform the following. 1) Set the RF communications test set to the transmit mode. 2) Set audio filtering from <20 Hz to 15 kHz. 3) Set to FM demodulation with +/- peak deviation. 4) Connect oscilloscope to the demodulated output. 5) Select the mid band channel on channel select inputs CS2, CS1 and CS0 which has no tone on it. 6) Connect sinusoidal 1 kHz audio source to pin 4 microphone input and set to 100 mV peak-peak . 7) Ground PTT (pin 14) to transmit. 8) Adjust deviation pot R388 for peak deviation of 4300 +/- 100 Hz. 9) Stop transmitting, remove mic input and inject a 50 Hz +/- 20 Hz square wave into AUX_IN (pin 7) with the signal amplitude of your data source generator. Adjust R375 to get 3.0 +/- .1 kHz (1.5 +/- .05 for narrowband) deviation. 10) Adjust the balance pot R304 to give a flat sloop on the demodulated output oscilloscope waveform. 11) Readjust R375 to maintain 3.0 kHz deviation. 12) Stop transmitting by releasing the /PTT line on pin 14. *NOTE: Sub audible tone deviation is automatically set to be within 600 to 900 Hz after this adjustment on wide band tone channels. Maximum voice and tone deviation on wide band channels will then be 4800 to 5300 Hz. Narrow band tone deviation will be 350 to 500 Hz with overall deviation of 2400 to 2650 Hz. RECEIVER FRONT END TUNNING If the DTX-442 receiver appears to be less sensitive on one of the band edges the front end tuning coils may need readjustment. Connect a SINAD meter to the SPEAKER output (pin 12). Unsquelch the audio amp by grounding pin 11. Set the generator to the upper band edge frequency programmed at –120 dBm with +/- 1.5 kHz deviation. Adjust coil cores L101 and L102 in until SINAD starts to drop. Back off slightly to maintain best SINAD. Now, set generator to the lowest frequency programmed at –120 dBm. Similar SINAD readings as the high band edge frequency should be obtained. If not, adjust coils slightly. Recheck high end and balance performance. RECEIVER SQUELCH The DTX-442 is capable of two squelch operating modes. Also, both can operate simultaneously. See the theory above. The units can be configured as the user requires. When a low level signal appears the noise squelch opens when the carrier level with 1.5 kHz deviation is –120dBm or greater. When the signal appearing is –106dBm or greater the RSSI squelch opens the audio with an even faster attack time. The above levels are factory set levels. Ambient noise will affect the level at which the RSSI should be set. The squelch level ideally should be set on the desired frequency, in the actual location the radio will be used and connected to the desired antenna. The level should be set high enough to reject most false signals. If a very fast receiver decay time (or squelching after signal disappears) is needed the noise squelch should be defeated by turning the R144 pot fully counterclockwise. To adjust squelch levels for simultaneous use do the following: Set RSSI squelch level first: 1) Temporarily defeat noise squelch pot by turning R 144 to counterclockwise minimum setting. 2) Adjust RSSI pot R123 fully counterclockwise to squelch audio. Be sure AUX_MON line is high to allow squelching. 3) Set generator to –106dBm on channel desired with 1.5 kHz devia…

Text truncated - open the document above for the full version.

TYPE OF EXHIBIT: TRANSMITTER EFFECTIVE RADIATED POWER FCC PART: 1.1310 MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Transceiver FCC ID: AIERIT17-442 DATE: Dec 10, 2003 PROCEDURE: 1. The measurement for effective radiated power was taken at the RITRON, Inc. 3 meter test site. The measurement was via the substitution method. 2. The ERP measurement was made with a Hewlett-Packard Model 8560E Spectrum Analyzer and an Electro-Metrics LPA-25 log periodic antenna. 3. A substitution antenna, an adjustable dipole, was substituted for the DTX-442 on the turntable 3 meters from the pick up antenna. An RF signal generator was set for the frequency of the DTX-442 at 460.050 MHz with a 0 dBm output level. 4. The height of the LPA-25 receiving antenna was varied to pick up maximum signal. 5. The DTX-442 was programmed for transmitter operation on 460.050 MHz at the 5.0 watt maximum obtainable from the unit. The unit was then terminated at the antenna port with a Nearson RAM1545 antenna, the only antenna available for this product from RITRON. 6. The DTX-442 antenna was then positioned on the turntable and the above procedure used to obtain maximum level at the receiving dipole. TYPE OF EXHIBIT: TRANSMITTER EFFECTIVE RADIATED POWER FCC PART: 1.1310 MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Transceiver FCC ID: AIERIT17-442 DATE: Dec 10, 2003 CALCULATIONS: The effective radiated power can be calculated as: ERP(dBm) = Pr(dBm) -- Pref(dBm) + Pgen(dBm) – Cable(dB) – Ga(dBd) Where: Pr is the power level of the radio’s emission at the receiving antenna output. Pgen is the RF signal generator level at the substitution antenna input. Pref is the power level of the substitution antenna emission at the receiving antenna output. Cable is the generator cable loss. Ga is the gain of the substitution antenna relative to a dipole. ERP(dBm) = 4.5 – (-29.7) – 0 – 1.9 –0 = 32.3 dBm ERP(watts) = antilog((ERP(dBm) – 30)/10) ERP(watts) = 1.7 watts RESULTS: Cable Pr(dBm) Pref(dBm) Pgen(dBm)loss(dB)Ga(dB) ERP(dBm)ERP(W) 4.50 -29.7 0 1.9 0 32.3 1.69 TYPE OF EXHIBIT: TRANSMITTER EFFECTIVE RADIATED POWER FCC PART: 1.1310 MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Transceiver FCC ID: AIERIT17-442 DATE: Dec 10, 2003 PROCEDURE: We will determine the minimum safe operating distance for this occupational device. Converting from ERP to EIRP we multiple by 1.64. EIRP(W) = 1.7 x 1.64 = 2.79 W Power density as related to EIRP is: S(W/m 2 ) = EIRP/4πr 2 where r is distance from the source in meters. Rearranging for distance: _________ r = √(EIRP/4πS) The MPE for a device operating in the occupational environment is 1 mW/cm 2 Converting to W/m 2 we get 10 W/m 2 . ___________ r = √( 2.79 /4π 10) = .149m Thus, at a distance of 15 cm or greater the MPE for occupational use is met. TYPE OF EXHIBIT: TRANSMITTER EFFECTIVE RADIATED POWER FCC PART: 1.1310 MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Transceiver FCC ID: AIERIT17-442 DATE: Dec 10, 2003 STATEMENT: The following statement appears in the User/Maintenance manual regarding RF safety: This product has been evaluated for compliance with the maximum permissible exposure limits for RF energy at the maximum power rating of the unit with the whip antenna available from RITRON. To ensure compliance with the Occupational/Controlled Exposure maximum limits, all persons must be at least 20 cm (7.9 inches) from the antenna while the unit is transmitting. Other antennas may require lesser or greater distances to meet the limits depending upon their gains relative to that tested. Higher gain antennas are capable of yielding a higher RF energy density in the strongest part of their field and would, therefore, require a greater separation from the antenna.

******************************************************************************************************************* * DTX-442 Test Results ******************************************************************************************************************* * MANUFACTURER: RITRON, INC. 505 West Carmel Drive Carmel, IN 46032 MODEL: DTX-442 TYPE OF UNIT: UHF-FM Two Way Radio Transceiver Module FCC ID: AIERIT17-442 DATE: Nov 5, 2003 The following is a list of attached exhibits required by the Federal Communications Commission for the application to and grant of FCC Type Acceptance. List of Test Equipment Used 2.947 (d) pg 2 Required Measurements 2.1033 (c)(14) Radio Frequency Power Output 2.1046 pg 3 Final RF Power Transistor Current 2.1033 pg 4 Transmitter Audio Ov…

Text truncated - open the document above for the full version.