Voice Recording Circuit HK828 and LM358 based on the supply voltage 9-14 volt DC Microphone with 45 seconds voice recording can be done recording the sound level rises to the outlet to an amplifier can connect a record eight separate section hiding the corresponding button with the records can be accessed
Voice Recording Circuit
Single-chip, high-quality voice recording and playback solution User-friendly, easy-to-use operation – No external ICs required – Programming & development systems not required – Minimum external components -Level-activated recording & edge-activated playback Non-volatile Flash memory technology switches – No battery backup required
Low power consumption User-Selectable messaging options – Operating current: 25 mA typical – Random access of multiple fixed-duration messages – Standby current: 1µA typical – Sequential access of multiple variable-duration messages -Automatic power-down Chip Enable pin for simple message expansion
Source: http://www.siliconchip.com.au/cms/A_109626/article.html
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Hand Drill Battery Charge Controller with PIC16F88 Microcontroller
Battery Charge circuit Frequently used in technical service, especially cordless screwdriver, drill bits designed for a charging circuit for the programming, led indicator has a lot of features such as temperature control. Microcontrollers are used in charge control circuit PIC16F88
Microcontroller Battery Charger Circuit Specifications