High-sensitivity field strength meter
The circuit employs a TL081 operational amplifier, known for its low noise and high input impedance, making it suitable for amplifying weak RF signals. The RF signal is initially captured by a diode (CR1), which serves as a rectifier, converting the RF signal into a usable voltage level. This rectified signal is then fed into the non-inverting input of the TL081 (IC1).
To optimize the performance of the amplifier, the circuit includes a feedback resistor network that sets the gain of the amplifier. The gain can be adjusted using a 100-ohm potentiometer, allowing for precise control over the full-scale sensitivity of the circuit. This feature is particularly important in applications where the input signal levels may vary significantly, enabling the user to tailor the amplifier's response to the specific requirements of the RF signal being processed.
The output of the TL081 can be connected to further signal processing stages, such as filters or additional amplification, depending on the application. Proper bypass capacitors should be placed near the power supply pins of the TL081 to ensure stability and reduce power supply noise. Additionally, it is advisable to include protection components, such as clamping diodes, at the input to safeguard the operational amplifier from potential overvoltage conditions caused by excessive RF signal levels.A TL081 (IC1 op amp is used to increase sensitivity. RF signal is detected by CR1 and is then amplified by IC1. Full-scale sensitivity is set with the 100 potentiometer.
Related Circuits
This project illustrates various features of the PIC16F687 microcontroller, including ultra-low power wake-up, serial communications, and nanowatt technology. The device can serve multiple purposes, such as measuring the water level in a rainwater tank or a water tank in...
A digital frostpoint hygrometer was developed for measuring water vapor at NOAA. This new hygrometer was created using AVR microcontrollers and other digital electronics, referencing an old analog instrument. The circuit board layout was designed using Altium DXP, and...
Ammeter is a great addition to any Laboratory Power Supply as it will measure the current consumption and help you determine if there are any problems with the circuit that you are building or testing. This ammeter is capable...
The ammeter measures currents from 100 pA to 100 µA without the use of expensive high-value resistors. Accuracy at 100 µA is limited by the offset voltage between Q1 and Q2, and at 100 pA, it is limited by...
For an introduction to the liquid-level inclinometer and a description of the apparatus and early work on the instrument, refer to Inclinometer Performance. This documentation records day-to-day work on the instrument from February 2008 onwards. Section headings are provided...
A copper mesh measuring 10 cm x 10 cm is situated in a vacuum chamber and connected to a BNC connector via a 24 cm copper wire. The objective is to rapidly switch the voltage across the mesh (referenced...