Newest circuit diagrams
6 Zone Alarm with 7 Segment Display
This alarm system has 6 independent zones, 1 timed entry/exit zone, a 7 segment LED display and a test or walkthrough facility. Suitable for a small office or home environment, it can also be adapted to use a combination lock or keypad to set and reset the alarm. Read more...
TDA2030 8w Amplifier
An 8 watt amplifier made with the TDA2030 IC. Built two such units for a stereo amplifier. Read more...
Self-powered Fast Battery-Tester
Tests 1.5 to 15 Volt cells Two-LED display, no power supply required Read more...
Snore Alarm
The idea behind this snore alarm, is just to rouse the snorer, not the entire household. To wake the sleeper, vibration is used, not an audible alert. The vibration is provided by a small motor housed in a small 35mm film case, which can be placed under the sleepers mattress or pillow. This circuit has a level control and peak display indicator, a variable trigger threshold and trigger indication. Read more...
Arduino MQ-7 Carbon Monoxide Sensor Circuit
The carbon monoxide sensor we will use is the MQ-7 sensor. This is a sensor that is sensitive to effects of CO. Carbon monoxide (CO) is a very dangerous gas which is odorless, colorless, and tasteless, so it cannot be smelt, seen, or tasted. A person really would have no idea that they are breathing in CO besides the fact that they would start to feel horrible. Read more...
Digital Combination Lock
A multiple input combination loack using CMOS counter IC's. Flexibility and code change is allowed by changing output connections. Read more...
60W Bass Amplifier
Low-cut and Bass controls. Output power: 40W into 8 Ohm and 60W into 4 Ohm loads Read more...
