Wiring schema blogs

This test device circuit in principle is equal by means of tester using IC 555. Op amp which must in test connected as simple square wave oscillator. At the time of push button S1 is closed [by] concurrent input, operation brace hewed to reference strain alighted from by output strain and voltage divider R2/R3. Current passing R1 applied to fill condenser C1 until strain at shoot input so reaching the same price with reference strain. Because brace can work as benchmarking, hence its the output level will change state causing yields an strain reference which its the polarity at the opposite. Charging current for C1 then will flow with opposite orientation until new reference strain reached and all cycle is upper will be repeated. If high output, transistor T1 will pass and LED D1 will turn on. This transistors participated that other operation brace by using the same output, but its(the output current is less than IC 741 can be tested. this circuit requires power supply positive and negative, and will work carefully if attached with two batteries 9 V.