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Ritron SST-444 Instruction Manual

Uhf-fm handheld transceiver
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Download this manual See also: Owner's Manual
TYPE OF EXHIBIT:
FCC PART:
MANUFACTURER:
MODEL:
TYPE OF UNIT:
FCC ID:
DATE:
Included in this exhibit is a draft of the Maintenance and Operating Manual for RITRON Model Patriot
SST-444 UHF-FM Handheld Transceiver.
Specifically, this manual includes a technical description of the SST-444 sufficient to establish compliance
with the technical standards of the applicable rule part(s).
This includes, but is not limited to, the following items required under FCC Part 2.1033 (c):
(2)
FCC Identifier.
(3)
A copy of the installation and operating instructions.
(4)
Type of emission.
(5)
Frequency range.
(6)
Range of operating power, and means to provide variation in operating power.
(7)
Maximum power rating.
(8)
DC voltage chart.
(9)
Tune-up procedure.
(10) A description of all frequency determining and stabilization circuits. A description of the circuits
used to suppress spurious radiation, limiting modulation, and limiting power.
(12) Drawing with labels for controls and complete circuit diagrams.
Signed:
Michael A. Pickard - Project Engineer
INSTRUCTION MANUALS
2.1033 (c)(3)
RITRON, INC.
505 West Carmel Drive
Carmel, IN 46032
SST-444
UHF-FM Handheld Transceiver
AIERIT13-450
July 7, 2000

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Summary of Contents for Ritron SST-444

  • Page 1 AIERIT13-450 DATE: July 7, 2000 Included in this exhibit is a draft of the Maintenance and Operating Manual for RITRON Model Patriot SST-444 UHF-FM Handheld Transceiver. Specifically, this manual includes a technical description of the SST-444 sufficient to establish compliance with the technical standards of the applicable rule part(s).

  • Page 2: Table Of Contents

    TABLE OF CONTENTS SECTION TOPIC PAGE SST-444 SPECIFICATIONS GENERAL RECEIVER TRANSMITTER INTRODUCTION GENERAL Inspection Model Identification FCC REGULATIONS Licensing Safety Standards BATTERY CARE CHARGING BATTERY REPLACEMENT PRECAUTIONS DESCRIPTION OF CONTROLS AND CONNECTORS Fig. 2 Controls and Connectors Belt Clip Installation...
  • Page 3 MODULATION BALANCE TRANSMITTER TONE DEVIATION TRANSMITTER VOICE DEVIATION TRANSMITTER POWER RECEIVER SENSITIVITY AND SQUELCH RECEIVER NOISE SQUELCH SYNTHESIZER SST-444 VOLTAGE CHART Measurement Conditions SST-444 Voltages SST-444 SCHEMATIC REFERENCE PARTS LIST SST-444 CASE ASSEMBLY PARTS LIST SCHEMATIC AND PART PLACEMENT DRAWINGS...
  • Page 4 Radio Transmitter Power Measurements The SST-444 was designed to produce a minimum of 3.5 Watts of Transmitter power at nominal battery voltage (+7.2 VDC), throughout the radio’s operating frequency range. Measurements are made with the RITRON SST-SRVBD RF service module connected to the radio antenna terminal.

  • Page 5: Sst-444 Specifications

    11.5 oz. with battery pack Enclosure Material: Lexan Polycarbonate Environmental: Splash resistant and shock and vibration per RITRON Drop Test (6 ft. drop onto concrete on all six sides) Antenna Fitting: 1/4" - 32 x 1/4" threaded External RF Test Jack:...

  • Page 6: Receiver

    3.5 mm, disconnects the internal speaker for external earphone, speaker / microphone, or headset. Also provides cable connection for PC programming. Microphone/PTT/Chg Jack: 2.5 mm, for external speaker/microphone, headset or RITRON model BC-A wall charger Push Button Controls: On/Volume Up...

  • Page 7: Transmitter

    SST-444 SPECIFICATIONS TRANSMITTER RF Power Output: Programmable per channel for high or low power High : 4 Watts (3.5 Watts minimum @ +7.2 VDC) Low: 1 Watt Wide Mode Narrow Mode Emission Designator: 16K0F3E 11K0F3E Deviation: +/- 5.00 KHz +/- 2.50 KHz...

  • Page 8: Introduction

    Examine the equipment immediately after delivery and report any damages to your shipping company. Model Identification The SST-444 model, serial number and FCC Identification are displayed on a label located on the back of the radio beneath the belt clip. FCC REGULATIONS...

  • Page 9: Battery Care

    To charge the battery using a RITRON cube charger - plug the charger cord into the smaller of the two jacks on top of the radio. Then plug the cube into a 110 VAC outlet. The green lamp lights while the battery is charging, and should go off only when the cube is unplugged.

  • Page 10: Battery Replacement

    The contacts must not touch the radio PC board. Fig. 1 Battery Replacement PRECAUTIONS • Use only RITRON-supplied chargers; other chargers might cause fire, explosion, or other damage to the radio. • Do not "fast-charge" a brand new battery pack. Otherwise, the battery might be damaged. •...

  • Page 11: Description Of Controls And Connectors

    The battery door on the case bottom may be removed to access the battery. (Refer to the battery section of this manual.) Drop-in Charger Contacts Two charger contacts in the bottom of the SST-444 radio case allow the battery pack to be charged using an optional RITRON drop-in charger (model BCPS-FS). Jack Cover This rubber cover seals out dust and moisture, etc.

  • Page 12: Belt Clip Installation

    DESCRIPTION OF CONTROLS AND CONNECTORS Antenna Jack Cover Vol Down/Off Audio Accessory Jack On/Vol Up Charge Jack Push-to-Talk Speaker Channel Selector Microphone Battery Access Door (Case bottom) Battery Charger Contacts (Case bottom) Fig. 2 Controls and Accessory Connectors Belt Clip Installation If you are going to attach the belt clip to the handheld, follow these instructions: 1) The belt clip is fastened to the radio case back with the Philips head screw provided.

  • Page 13: Operation

    There are two types of squelch used in the SST-444 portable. First is carrier squelch. This lets you hear all broadcasts on your channel strong enough for the radio to detect, and silences noise. Second is one of the selective signaling or “tone squelch”...

  • Page 14: Transmit

    Turn off the radio and try again. A long, low-pitched tone means the battery voltage is too low to operate the radio. In this case, recharge the battery. If you cannot correct a problem, consult an authorized Ritron service facility or Ritron.

  • Page 15: Optional Radio Tones

    OPERATION OPTIONAL RADIO TONES The SST-444 can be programmed using the RITRON PC Programmer for optional alert tones. Receive Squelch Tone A short tone sounds at the end of each received transmission to indicate that you may transmit. Busy Channel Transmit Inhibit If a user is transmitting on your radio frequency without your tone, you will not be allowed to transmit.

  • Page 16: Troubleshooting

    OPERATION TROUBLESHOOTING If you have trouble operating the handheld, review the radio controls and operation sections. If you think the radio is malfunctioning, check the table below. Problem Possible Solutions GENERAL The radio does not work at all. Make sure that the battery is installed correctly, as shown in FIG-1.

  • Page 17: Tone Coded Squelch

    However, if the battery appears to be good after you try the second charger, the first charger might be faulty. If you think that an accessory is not operating properly, contact your dealer or RITRON. (Radio accessories come with a 90-day limited warranty.) 2) Reception can often be improved by moving a short distance.

  • Page 18: Programming The Radio

    PROGRAMMING THE RADIO Each SST-444 may be programmed to operate on up to 4 channels. The SST-444 may be programmed using its Push-to-Talk switch or an optional RITRON programming kit. PTT (PUSH-TO-TALK) PROGRAMMING allows you to program any channel to one of the radio frequencies listed in Table 1 and any Quiet Call code listed in Table 2.

  • Page 19: Ptt Programming The Radio

    PROGRAMMING THE RADIO PTT Programming the Radio Four valid digits must be entered for the radio to accept PTT programming. The first two digits entered is the frequency code from Table 1, followed by the two digits for the QC code from Table 2. 1.

  • Page 20: Computer Software Copyrights

    The RITRON, Inc. products described in this manual include copyrighted RITRON, inc. computer programs. Laws in the United States and other countries grant to RITRON, inc. certain exclusive rights in its copyrighted computer programs, including the exclusive right to distribute copies of the programs, make reproductions of the programs, and prepare derivative works based on the programs.

  • Page 21: Programming The Radio Using A Pc Computer

    The DB-25 plugs into the computer’s serial port, the modular plug into the SST-SRVBD modular jack. 4) An adapter for use with SST-444 portables. This adapter mates the modular plug to a 3.5 mm plug, for connection to the handheld audio jack.

  • Page 22: Description Of Features

    PROGRAMMING THE RADIO Descriptions of Features Automatic Inactivity Turn-off - The radio automatically shuts itself off if four hours go by without the microcontroller detecting input from the volume, PTT or channel controls. Battery Saver - Enabling this option allows the radio to go into battery saver mode when the radio remains idle.

  • Page 23: Sst-444 Theory Of Operation

    Pin 13 of IC301 turns on Q303, which keeps Q304 turned on after SW301 has been released. Power is removed from the SST-444 by pressing the VOL DN/OFF switch SW302 until a beep is heard from the speaker, at which time Q304 is turned off.

  • Page 24: Reference Oscillator

    SYNTHESIZER The SST-444 radio is built around a common phase-locked loop (PLL) that consists of a voltage-controlled oscillator (VCO) and a frequency synthesizer. The PLL generates both the receiver 1st local oscillator and transmitter carrier signals. Control signals from microcontroller IC301 and Reference oscillator Y302 are...

  • Page 25: Vco / Buffer Amplifiers

    Oscillator Modulation When the SST-444 is in transmit, modulation balance control IC306E passes TX audio through to the VCO modulation input at R416. TX audio is applied to varactor CR403 to modulate the VCO. TX audio is also routed to the Pin 1 input of TCVCXO reference oscillator Y302. Low frequency tones modulate the reference oscillator because the synthesizer is not able to track them.

  • Page 26: Receiver

    R113. The Pin 11 output of the noise amplifier is applied to a biased noise detector CR103, with the output connected to an A/D input of IC301 at Pin 19. The SST-444 is serial programmed to set the squelch threshold and hysteresis.

  • Page 27: Voice Band

    Two PIN diodes (CR201, CR101) and associated components form the antenna switching circuit. With the SST-444 in receive mode, no voltage is applied to the PIN diodes and they do not conduct. This reverse biases CR201 to prevent the transmitter amplifier from affecting the receiver tuning and removes CR101 from the receiver input.

  • Page 28: Transmitter

    Q203 at Pin 1. The 50Ω output of Q203 is matched to the antenna switching circuitry and applied to the antenna through the low-pass filter. The RF power output is programmable by a licensed RF technician. The SST-444 can be programmed on a channel-by-channel basis for low or high power operation. The power control digital Potentiometer IC306B is used to adjust the Q203 gate voltage and set RF power output.

  • Page 29: Sub-Audible

    8-bit A/D inputs for processing analog signals. DESCRIPTION RESET is connected to the SST-444 +5V to start the radio in a known state on power up. TX KEY input is pulled LOW when either the internal or external PTT switch is pressed to initiate transmitter operation.
  • Page 30 SST-444 THEORY OF OPERATION DESCRIPTION +V SW output is HIGH when the radio is turned on, keeping pass transistor Q304 turned on via Q303 to supply power to the radio. GROUND sets the upper reference level for the A/D and is connected to the regulated +5 VDC.

  • Page 31: Recommended Test Equipment

    Voice deviation with tone – narrow band Power Low transmitter power High transmitter power 8) After you have completed alignment of the SST-444, turn the radio off. This will remove the test frequencies and return to operation on the customer’s programmed frequencies.

  • Page 32: Reference Frequency

    SST-444 ALIGNMENT PROCEDURE REFERENCE FREQUENCY 1) Make sure that the unit has been switched on and is at room temperature (approximately +25° C) 2) Select “Frequency” from the PC Programmer “Alignment” screen. 3) Set the RF communications test set to the Alignment Frequency on the Alignment screen.

  • Page 33: Transmitter Voice Deviation

    RECEIVER SENSITIVITY AND SQUELCH The SST-444 receiver is factory tuned for a frequency range of 460 - 470 MHz. The SST-444 receiver is configured from the factory for Wide Band operation, with a Narrow Band Model available as an option.

  • Page 34: Receiver Noise Squelch

    SST-444 ALIGNMENT PROCEDURE 5) Set the RF Communications Test Set generator to the programmed receive frequency at a RF level of –120 dB. Modulate the RF signal with a 1 KHz tone at 3 KHz deviation for wide band, 1.5 KHz deviation for low band.

  • Page 35: Sst-444 Voltage Chart

    Supply voltage at 7.5 VDC, radio in operating mode, volume control at minimum, power strobe enabled, transmitter set for full power. IMPORTANT: Because the SST-444 portable is constructed with grounding sub-planes, use a system ground in the same proximity as the circuit being measured. All readings indicated as GND are true system ground.
  • Page 36 SST-444 VOLTAGE CHART DEVICE Transmit Receive Standby DESCRIPTION CR401 Biasing CR402 VCO tuning → → → 1.5 – 4.5 VDC VCO tuning voltage CR403 VCO modulation CR404 TX/RX VCO switching IC101 RX FM-IF subsystem IC301 Microcontroller → → → → 0.0 VDC on Channel 1 else 5.0 VDC →...
  • Page 37 SST-444 VOLTAGE CHART DEVICE Transmit Receive Standby DESCRIPTION IC302 EEPROM IC303 Audio processing IC304 Audio signal switching IC305 Audio processing...
  • Page 38 SST-444 VOLTAGE CHART DEVICE Transmit Receive Standby DESCRIPTION IC306 Audio signal level control IC307 Audio amplifier IC308 Tone low pass filter IC309 +5 VDC voltage regulator...
  • Page 39 SST-444 VOLTAGE CHART DEVICE Transmit Receive Standby DESCRIPTION → → → → 3.6 MHz clock signal IC401 Frequency synthesizer → → → 1.5 – 4.5 VDC VCO tuning voltage 2.2 → 2.2 → → 14.4 MHz reference signal Q 101...
  • Page 40 SST-444 VOLTAGE CHART DEVICE Transmit Receive Standby DESCRIPTION Q 301 PTT detection Q 302 PTT detection Q 303 Battery +V switching Q 304 Battery +V switching Q 306 +5V switching Q 307 Audio amplifier enable Q 308 Audio amplifier +V switching...

  • Page 41: Sst-444 Schematic Reference Parts List

    SST-444 SCHEMATIC REFERENCE PARTS LIST NOTE: This parts list reflects the most current component values. If a component value given in the schematic differs from this list, the parts list should be considered the most current. Last Update: June 13, 2000...
  • Page 42 SST-444 SCHEMATIC REFERENCE PARTS LIST Ritron PN Description Y Theta C302 15181102 .001uF CAPACITOR, CHIP, 0402, X7R, 5/10% C303 152B4226 22uF 6.3V 3.4 X 2.8 CHIP TANTALUM CAP C304 15181102 .001uF CAPACITOR, CHIP, 0402, X7R, 5/10% 1261 4590 Bottom C305...
  • Page 43 SST-444 SCHEMATIC REFERENCE PARTS LIST Ritron PN Description Y Theta C363 152B6106 10uF 10V 3.4 X 2.8 CHIP TANTALUM 1231 C364 15119104 .1uF X7R 0805 25V CERAMIC CHIP CAP 1058 Bottom C365 01503212 220MF 10V ELT CAPACITOR, 5mm HEIGHT 1491 5052 0.302...
  • Page 44 SST-444 SCHEMATIC REFERENCE PARTS LIST Ritron PN Description Y Theta FUSE F301 06000040 WIRE; #40AWG TINNED BUS (INCHES) Bottom INTEGRATED CIRCUITS IC101 31030003 MC3371D SUBSYSTEM IC, SO-16 1158 Bottom IC301 314G0301 MCU, 28 PIN, SOIC, SST/JMX 4-SERIES v01 2546 Bottom...
  • Page 45 SST-444 SCHEMATIC REFERENCE PARTS LIST Ritron PN Description Y Theta Q105 4821003B MMBT918LT1 VHF SOT23 (3B) 1374 Bottom Q201 4801002A MMBT3906 PNP, SOT23 3268 Bottom Q202 4801001Q MMBT5088 NPN, SOT-23 3268 Bottom Q203 04801503 M68710H 2W RF MODULE 450-470 MHz 6.0V...
  • Page 46 SST-444 SCHEMATIC REFERENCE PARTS LIST Ritron PN Description Y Theta R313 47180104 100K OHM, RESISTOR, CHIP, 0402,1/16W,5% 1184 2376 R314 47180472 4.7K OHM RESISTOR, CHIP, 0402, 1/16W, 5% 1260 2375 R315 47180102 1K OHM RESISTOR, CHIP,0402, 1/16W,5% 2841 Bottom R316...
  • Page 47 43.650 MHz Crystal Filter +/-6.0KHz UM-1 3524 YF102 02301013 FILTER,CERAMIC,450KHz,+/-7.5KHz,6 POLE 1614 HARDWARE 1750240B PCB, ML4 FR4 5UPM, .062 MIX, SST-444 25602500 CRYSTAL SUPPORT, RUBBER PAD, SMALL/UM-1 06001021 #28 AWG STRANDED WIRE; RED (INCHES) 06001023 #28 AWG STRANDED WIRE;GREEN INCHES 06001026 #28 AWG STRANDED WIRE;...

  • Page 48: Sst-444 Case Assembly Parts List

    SST-444 CASE ASSEMBLY PARTS LIST Ritron PN Description MAIN CASE ASSEMBLY 13250000 CASE W/INSERT, PLASTIC, SST BLACK 13578000 DOOR, BATTERY, PLASTIC, SST 2-PC 13588000 LATCH, BATTERY DOOR, PLASTIC SST 2-PC 25106400 BATTERY DOOR HINGE RETAINER 25201500 RETAINER, PLASTIC, PTT, SST...

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