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Figure 2 - Transmit Audio Circuits

LBI-38546

3

Summary of Contents for 19D902304G2

Page 1: ... front of the radio housing assembly and connects to the logic board through an 18 pin connector J703 The audio board contains the following primary circuits transmit audio and data receive audio and data Both the transmit and receive audio and data signals include tones A general description of the primary circuit functions followss CIRCUIT ANALYSIS TRANSMIT AUDIO CIRCUITS Transmit audio includes...

Page 2: ...ation of the low frequencies The two filters provide 18 dB Octave of low frequency attenuation and unity gain S Data Voice Mute controls FET transistor Q602 to pro vide audio mute RX Mute allows both voice audio and controller generated Signal tones to be summed at Speech Audio Amplifier U603A Capacitor C617 provides 6 dB Oc tave speech deemphasis for the circuit The RX Audio output at J703 6 is b...

Page 3: ...Figure 1 Audio Board Block Diagram LBI 38546 2 ...

Page 4: ...Figure 2 Transmit Audio Circuits LBI 38546 3 ...

Page 5: ...Figure 3 Receive Audio Circuits LBI 38546 4 ...

Page 6: ...PARTS LIST LBI 38546 5 ...

Page 7: ...LBI 38546 OUTLINE DIAGRAM 19D902304 Sh 1 Rev 3 19D902305 Component Side Rev 3 COMPONENT SIDE 19D902304 Sh 1 Rev 3 19D902305 Solder Side Rev 3 SOLDER SIDE 6 ...

Page 8: ...NTEGRATED CIRCUITS LBI 38546 OPERATIONAL AMPLIFIER U301 U303 U602 U603 19A700086P4 OPERATIONAL AMPLIFIER U601 19A134764P1 OPERATIONAL AMPLIFIER U604 U605 19A701789P1 VOLTAGE REGULATOR U606 19A704073P2 7 ...

Page 9: ...SCHEMATIC DIAGRAM LBI 38546 AUDIO BOARD 19D902304G2 19D902306 Sh 1 Rev 10 8 ...

Page 10: ...SCHEMATIC DIAGRAM LBI 38546 AUDIO BOARD 19D902304G2 19D902306 Sh 2 Rev 7 9 ...

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