Analog and Digital Voltmeter using ICL7107
This Circuit is a DPM or digital panel meter. It has a analog bar graph display and a 3-1/2 digit digital display. ICL7107 is used in the 200mV configuration. U4A opamp LF353 amplifies the...
Voltage to Frequency Converter ICL8038
This circuit is alternative approach to same solution show in earlier post. Here i have put the complete circuit in PNG format. 8038 is a marvelous chip, a custom monolithic analog computation unit, a...
Electronic Fifteen LED Roulette
The following was submitted on July 11th, 2007. Message: I want to combine Ne555 with 74154 IC.The indication of the outputs must be shown with LED’s but up to so far it need 15...
Flashing Mains Neon Lamp
Here is a Neon Flasher circuit (untested) for a user request at Circuits FAQ. This can be built into a switchboard or a gadget for indicating Live Power. D1-C1 form a simple half-wave rectifier,...
Interface ICL7135 Voltmeter to 89C52
This circuit is a Parallel interface between 89C52 of Atmel with 7135 of Intersil. With This circuit you can read analog data of both polarities. You can change the range scale with extra circuits,...
WorkBench Dual Power Supply
I will just explain part of this circuit. D9 and D10 provide a low cost -1.4 from -5 V. This is needed to reach near 0.00 for LM317 Min. setting. An LED also can...
RS485 Modbus – Wireless Interface
I am working on alarm systems and would like assistance in designing wireless link for the unit, ie sensors to control panel, control panel to monitoring station. I noticed most of the circuits available...
Analog Dial Amps-Volts-Ohms meter
This was designed, keeping in mind, that sometimes we have few components available and you could not carry your DMM somewhere, but you have to make some instrument for a quick need with what...
