Satellite 2-way intercom circuit

Satellite 2-way intercom circuit

Figure 1 is a duplex intercom electronic cable (phone intercom cord call) created fans. The machine is a call, a two-way intercom system, micro-MP3 and other functions of the public network of angles and places to do an interview with special tools.

The district comprises: circuit micro, anti-side your circuit and power amplifier, microphone your amplifier circuit.

Radio circuit two product see Figure 1, providing two wires, make sure that on the form is connected to a fixed telephone network.

Job:

Radio two hooks (switch s1 defines two "hooks"), is the system in the vicinity of the switch S2, in the standby mode.

The system uses two Kasiraadiosaatjate, not host externally when pick the system into standby mode, the appellant, the first person, another person. It is clear: as the code element "" "one called parts of the party" "" call the pages. A special machine GB GB battery work "sound circuits;" BL, BL and VT4 VT4 speakers as part of the "transmitter circuit if resistor R9 R9" ultimately control of the circuits, TG, TG sound "Parameter set is too low, so that the output of IC2 IC2 signal," ring, BL, BL "is pronounced. C13, C13 "to avoid bad heart rate can cause of malfunction of the circuit ring could cause an explosion."

If to talk about the other party, is expected to speed up (the SL Kit 'Speech'), this time that callers ringing voltage in the district; lost their jobs Call chain (Figure 1 microphone, microphone amplifier, your circuit amplifier circuit on the consumer side, call the light chain, an important circuit) is thrilled to work indicator light call VD2. Speaker output circuit IC1 BL, press and hold the call button, for a positive voltage, triggered by the appellant "Line sound is called circuit" signal if the TG is usually not possible, the threshold, the output of IC2 increase communication with SB-L1, R8 "C13" began, the figure of the wrestler, VT4, calling the President "with a view" to promote. "You hear a call from the BL hook (also known as s1 ' invitation 'speak') loses his job, perhaps half of the circuit voltage ringtone;" Speaker "is circuit output of IC1 BL controlled", to stop calling on the ring. At this time, the callee receives a call, call signaling circuit voltage that the size of the system may result in the closure of the target network "voice interactive, VD2, only two half-duplex will send / retrieve results a delicate call." The call ends on both sides, there should be a reliable connection (s1, s1 is set to "Standby"), for the next call waiting. A Cup is the call that rely on other calls are unreliable.

If the two parties 'Invitation', the call button press person a different ring tone circuit does not have relay capacitor C7, C7 clutch "DC block the effect that this will have impact on the normal pronunciation. Then only has when the "clock" is the system in the "call" and the second when the party, including the speech (author of the call), press the button of the complaint on the page (called) circuit party itself a BL "name.

An introduction to the circle unit

Electrets microphone BM voltage electro acoustic performance, field-effect transistor. Figure 1, R1, C1 RP1 micro ignition components supply circuit. You can get a filter capacitor C1; The sensitivity of the microphone can pick up is regulation.

VT1, VT2 is connected directly to the composite offset, the depth of the negative feedback from the microphone amplifier. This circuit is used as a point of stability, the correct answer, the circuit is easy and convenient for debugging. R2 is the collector of VT1, VT2 offers resistance load also Peruseroon. R3, R6 is VT1, VT2 channel current feedback series VT1 and VT2, R4 the cause of resistance, so the parallel to the resistance of the feedback there, in place and will give DC VT1 stands. Amplifier to avoid the self excitation is used the C4, C3 can block the sound. C5 low frequency signal for access.

Two of audio amplification of the signal, which directly connected and see: T is the anti-side tone circuit. See the wiring of the shadow side transmitter, the primary coil of the transformer T C6 is densely bypass capacitor. Low input impedance output impedance radio signal-noise high and high, but even more radical report your anti-side. "Semitone" refers to a single call to the receiver (speakers or headphones), I heard the sound of his retro

Amplifier IC1 is low power single-supply amplifier LM386 IC, power supply power supply 9V, there is the power of 250mW 8O download. Control access to the volume, the characteristic frequency of the C11 can adjust R7 release. The BL and the ears of the circuit switch s1-2 speakers.

This machine is only a current supply continuously current alternative in the region, should be replaced by an AC adapter. Circuit of amplifier microphone microphone, sound anti-side circuit consists of R11, C15, C16, a control circuit VD1.

Light district R10 VD2 "separate composition" - when you're ready, you call and VD2. The "hook" is a light, is supposed to show visually the radio mode.

Components and the establishment of a selection

This machine adopts all components: VT1 ~ VT4 can be ss = NPN transistor with a capacity of 40-60 resistance of the various optional 0.25 W; Capacitor C7 600V voltage should be more than great weight at the end of the line, 16V. The transformer that can your anti-side T radio push-pull output transistor, primary and secondary schools in Zug, 8 ° load impedance transformer and the ratio of 3: 1 × 2 is the best, but also his injury. Connect 2 × 2 on / off switch or a special phone switch S1.

Debug of the pantograph 6 0 ~ 1mA, VT1, VT2 Ic2 = 0.8 ~ 2mA, change to the adjustment of the amplifier, but the R4 R4 is a public interest VT1.

A bit hard on the side of the track at the same time by adding an audio signal 0.3 VP - p, T, original volume of the amplifier output is less than the maximum RP2, better anti-debugging.