BCD Thumbwheel to Voltage Interface
This is a Proportional Controller where the setpoint is derived from a Thumbwheel switch. The conversion of Thumb-wheel Digital Data to Analog mV is similar to R-2R Weighted Resistor Network. In this case it...
Battery Backup for SRAM or Microcontroller
This circuit can be used as a low cost SRAM and Microcontroller or Microprocessor Battery Backup. All the diodes are 1N4148, The diodes prevent battery discharge back to power source. D8 gives a one...
Audio Visual User Interface with Ack
This circuit is an User Interface part of a Security Alertness Monitor that i designed decades ago. The circuits are here – Digital Circuits – Part 1 The RAM and RTC part is missing, i will add later....
Guard rings in strain gauge measurement
Hi… Can you please tell me as to what is a guard circuit used in bridges? Mail from SN The very high impedance amps for bridge circuits have inputs in tera ohms and bias...
Lighting a LED String – Serial Drive
Hi there, my name is steve. I would like to ask you about the best way or the most efficient way to supply LEDs. there are 36 small LEDs or 72 small LEDs (5mm)....
Electrometer, Gauss Meter and EMF Meter
Hey folks, I’m brand new here and to tinkering with electronics in general. I’m looking into building my own electroscope. My question is: What’s the difference between a static field and an EMF field?...
Voltage Attenuator Amp – DMM Project
LF356 opamp FET input is in a inverting amplifier configuration here. R4 + R5 make up Ri each 1/4 W MFR withstands 250V so both will take upto 500V. Use more in series for...
Thermocouple and Current Input Module
This input module converts J, K Thermocouple and 4-20 mA Inputs to 0-2V Full Scale. These can be used for any voltage/current inputs too. The RTD module can be modified more easily for Voltage...
