Schematic Rise

Showing posts with label line. Show all posts

Saturday, October 4, 2014

Standard low pass Phone Line Filter

Standard low-pass Phone Line Filter

The aloft diagram is a accepted low-pass blast band clarify (L1,C1,L3,C2). L2 and L4 are bare aback were ambidextrous with the Tip and Ring of a buzz band which may backpack up to 90VAC!.

I acclimated a agnate ambit on 3 phone-lines aback in the aboriginal 80s back I was active Scottsdale BBS and the filters performed fine. Additional advice can be begin in the ARRL Handbook, etc. For the two capacitors, the college the voltage the better, but the 400V types are the easiest to obtain.

Part and Descriptions

L1,L2 = 6.8mH, inductor
L3,L4 = 10mH, inductor
C1 = 0.022uF, 250-600V
C2 = 0.015uF, 250-600V

Via www. BenJammin.Net

Telephone line monitor Circuit Diagram

Telephone line monitor Circuit Diagram

This chic little circuit lets you almanac your buzz conversations automatically. The accessory connects to the buzz line, your band recorders microphone input, and the recorders alien ascendancy jack. It senses the voltage in the buzz band and begins recording back the band drops to 5 volts or less.

Parts
R1 270K 1/4 W Resistor
R2 1.5K 1/4 W Resistor
R3 68K 1/4 W Resistor
R4 33K 1/4 W Resistor
C1 0.22uF 150 Volt Capacitor
Q1, Q2 2N4954 NPN Transistor
D1 1N645 Diode
MISC Wire, Plugs To Match Jacks On Recorder, Board, Phone Plug

Notes
1. The circuit can be placed anywhere on the phone line, even inside a phone.
2. Some countries or states require you to notify anyone you are talking to that the conversation is being recorded. Most recoders do this with a beep-beep. Also, you may have to get permission from the phone company before you connect anything to their lines.

Tuesday, September 2, 2014

Line Follower Robot Sensor Concept

Line Follower Robot Sensor Concept - Sensor line detector is used in line follower robot is usually based on the principle of light reflectionto distinguish the line with the background color. In the dark color of the light absorption is greater than that of white light reflected to the sensor becomes smaller.

Position sensor to track the trajectory and the example circuit.

Line Follower Robot Sensor Concept

Light used for the introduction of the line is usually visible light and infra-red. Sensors for visible light are commonly used are LDR (Light Depending Resistance), while for the infrared light is atransistor and photo diode (photodiode). Sensors placed at the bottom of the frame to hang the robot, so that its position can be located just above the track to be read.

Saturday, August 9, 2014

Stereo line driver circuit

This is the schema diagram of a low cost stereo line driver is given here. The schema consists of only two transistors and few passive components. Each BC 109C transistor is wired as an emitter follower for driving each channel. The voltage gain of the emitter follower is unity, but it has a high current gain and low output impedance, ideal for driving long cables. The output impedance is around 16 Ohms at 1KHz.Since voltage gain is unity power amplifiers must be used at the listening end in order to drive loud speakers.

Notes.

* Assemble the schema on a general purpose PCB.
* The schema can be powered from a 12V battery or 12V DC power supply.
* The inputs and outputs must be connected with respect to ground as shown in schema.
* A power amplifier is needed at the listening end because the emitter follower has only unity voltage gain.
* The line driver schema must be place close to the audio source.