The hot melt glue that covers the circuit serves multiple purposes: It helps to keep the temperature even among the three transistors (to minimize thermal drift), it protects the components from physical damage, and it holds the battery holder on the board. As I used this probe last nigh to determine if a 384 MHz
RF Field Strength meter using AVR microcontroller using Atmega Read More »
Calculates and displays L and C from oscillation frequency using reference components. No relays, no range switching, a minimum of controls. And it is pretty accurate too! Note: After reading this article, check out the improved, modified An Even Better LC Meter… The 2 line x 16 character LCD shows the calculated inductance and the oscillation
A Pretty Good LC Meter Based on the AVR using ATTINY2313 Microcontroller Read More »
Measure current vs voltage or voltage vs current over limited range with good accuracy This was built on a phenolic board which was mounted on a plastic box. The box serves two purposes: It holds the circuit off the workbench, and it makes a nice, stable mount for the potentiometer. Find updates at www.projects.cappels.org I realized
A SIMPLE MANUAL CURVE TRACER using microcontroller USING ATMEGA Read More »
Downloads Download the AVRStudio assembly source for the program: M8DPM091109A.asm Download the AVRStudio hex file: M8DPM091109A.hex Find updates at www.projects.cappels.org Overview – A 10 bit digital panel meter for positive voltage only. – Input resistance: about 130k – Ranges: 0 to 10.20 volts and 0 to 102.3 volts. – Over range indication. This project came from friend named
A 10 Bit LED Digital Panel Meter With Auto Ranging Based On The ATMEGA8 Read More »
A well known L/C measurement circuit is pressed into service to make a bare bones measurement circuit. Download the AVRStudio assembly source: lgm031227I.asm Download the AVRStudio hex file: lgm031227.hex Left-to-right: The 5 volt regulator, the LM393 oscillator (a 0.047 uf capacitor is mounted on the LC circuit connector), the AT90S2313, and the serial connector to the LCD
LC Determination by Resonant Frequency Measurement using microcontroller using Atmega Read More »
I needed a way to measure hand-wound RF inductors in my second lab, and since I would only be doing this occasionally, I didn’t need anything fancy, and since once a friend finishes his AT90S1200-based design, I plan to make one myself, I figured I’d use this for less than a year, so I didn’t
RF Inductance Meter using microcontroller using Atmega Read More »
Its built into a plastic project box with an aluminum cover (on the bottom). The controls are as follows: Large golden knob is coarse tuning, small black knob with a blue index stripe is fine tuning, the green LED is the power on indicator, the slide switch is the on/off switch. The small black knob
HF/VHF/UHF TEST OSCILLATOR using microcontroller USING ATMEGA Read More »
This is design for a frequency meter based on AVR microcontrollers. Maximum input frequency is specified to be 30 MHz in the multi-chip configuration, and in single-chip configuration, there are both 5 MHz and 10 Mhz versions operating with 10 and 20 MHz crystals, respectively. All versions have 9 1/2 digit resolution. I have used
A Little More Serious Frequency Meter using ATtiny2313 microcontroller Read More »
A preamp that drives the CMOS counter input and a divide by 10 prescaler to extend the range of A Little More Serious Frequency Meter(elsehwhere on www.projects.cappels.org). (Above) Enclosed in a 16 cm x 16.5 cm plastic box, the preamp has a 60 cm cable to supply power and take the signal to the frequency meter/counter. The
Simplicity in circuitry was the design direction. Zero mass (firmware only with no physical components) would the ultimate achievement. This instrument doesn’t have any front panel controls because the user interacts via an RS-232 terminal program at 9600 baud. I needed a frequency meter for my experiments in Nondu, Thailand, where I really don’t have
RS-232 Freq. Meter/Pulse Generator Based on Atmel ATtiny2313 using microcontroller Read More »
