Position: Index > Electrical Circuit >
HIGH_ISOLATION_TELEPHONE_RINGER
2014-11-06 01:18
Declaration:We aim to transmit more information by carrying articles . We will delete it soon, if we are involved in the problems of article content ,copyright or other problems.
The diode rectifies the ringing signal to supply the operating power to the audio relaxation oscillator made up of L1, L2, R1, R2, and C. Moreover, L2 together with Q1 acts as an opto-isolator, totally isolating the telephone line from the rest of the circuit.The oscillator audio frequency is optically coupled to the photo-Darlington which drives Q2 and thus the speaker. The 10 μF capacitor is not large enough to smooth the ringing ripple completely. This results in frequency modulation of the audio oscillator giving it an attention-getting warble.
Maybe you like
Similar Circuit Diagram
- FM_wireless_microphone_using_and_ECG1014_and_ECG1017
- BLOOD_PRESSURE_REGULATOR
- Capacitor ESR Meter circuit
- 10000 h timing circuit with minutes and seconds
- Complete_TV_video_IF_amplifier_and_detector_system
- Phone minute beep decoder circuit with NE555, CD4017
- Ohms law
- EMOTE_TELEPHONE_RINGER
- Simple_dc_power_control
- CHROMA_CONIRQL_AND_COLOR_KILLER
- COLOR_BURST_GATED_OSCILLATOR
- TELEPHONE_AUTO_RECORD
- 460_KC_F_M_RECEIVER_FOR_WIRELESS_MICRO_PHONE
- HANDS_FREE_TELEPHONE
- Vector_computation_circuit_for_VC2_=_VA2___VB2_using_the_433
- OUTLINE_GENERATOR_FOR_TV_STUDIO
- 12_BIT_BINARY_2s_COMPLEMENT_D_A_CONVERSION_SYSTEM
- The RC phase-shift circuit with unchanged Output amplitude
- Ac_coupled_video_amplifier_with_single_supply
- SINGLE_FRAME_TV_PHOTOGRAPHY_TIMER
- CLASSIC_OP_AMP_ASTABLE_MULTIVIBRATOR
- SAMPLE_HOLD_DISCRIMINATOR
- Analog_video_switch_and_amplifier_with_direct_coupled_output
- BATTERYLESS_CARDIAC_PACEMAKER
- MICROWATTS_AT_QUIESCENCE