What Must todo

Have you anytime been application the modem or fax and addition abroad picks up the phone, breaking the connection? Well, this simple ambit should put an end to that. It signals that the buzz is in use by lighting a red LED. When the buzz is not in use, a blooming LED is lit. It needs no alien ability and can be affiliated anywhere on the buzz line, alike army central the phone.

Notes



1. This is a very simple circuit and is easily made on a perf board and mounted inside the phone.



2. LED1 and LED2 flash on and off while the phone is ringing.



3. Do not worry about mixing up the Tip and Ring connections.



4. The ring voltage on a phone line is anywhere from 90 to 130 volts. Make sure no one calls while you are making the line connections or youll know it. :-)



5. In some countries or states you will have to ask the phone company before you connect this to the line. It might even require an inspection.



6. If the circuit causes distortion on the phone line, connect a 680 ohm resistor in between one of the incoming line wires and the bridge rectifier.



Phone Busy Indicator Diagram Part List



R1 1 3.3K 1/4 W Resistor

R2 1 33K 1/4 W Resistor

R3 1 56K 1/4 W Resistor

R4 1 22K 1/4 W Resistor

R5 1 4.7K 1/4 W Resistor

Q1, Q2 2 2N3392 NPN Transistor

BR1 1 1.5 Amp 250 PIV Bridge Rectifier

LED1 1 Red LED

LED2 1 Green LED

MISC 1 Wire, Case, Phone Cord

Phone circuits are busy pointer. A busy signal is a signal that indicates that someone is trying to call a phone number but could not be contacted because the phone if it is not involved, or because the circuits are busy, calls are impossible to solve.

On many phones, busy signals take the form of a distinctive tone, but a busy signal can also be visual, as in the case yanga phone designed for users of deafness or hearing impairment. Many people are familiar with a busy signal sounds, because significantly different from the dial tone, a tone that indicates that the phone line is open and ready to be called.

In most cases, only a busy signal indicates that the person you are calling is a call. A busy signal will also sound when the phone is turned off. In this case, the signal indicates that there are no technical obstacles to placing the call, but calls can not be completed because the phone is in use.

In some cases, you can ask the operator to enter, if you call in an emergency, in this case the operator will interrupt the call and inquire whether the subject is willing to take your call.

Have you ever use a modem or fax and someone else pick up the phone, disconnect? Phone circuits are busy these simple pointers that will end all that. Menunjukkam phone signal is being used then the red LED. When the phone is not used, the green LED lights up. It does not require external power and can be connected anywhere on the phone line, even mounted inside the phone.

List of Components:

R1 = 3.3K 1/4 W Resistor

R2 = 33K 1/4 W Resistor

R3 = 56K 1/4 W Resistor

R4 = 22K 1/4 W Resistor

R5 = 4.7K 1/4 W Resistor

Q1, Q2 = 2N3392 NPN Transistor

BR1      = 1.5 Amp 250 PIV Bridge Rectifier

LED1   = LED red

LED2   = LED green

Others  = Wire, Containers, Telephone Cable

This circuit is very simple and easy to make on the board and installed on the phone. Try a series of telephone busy pointer