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 »
Briefly, • AC True Watts using two quadrant multiplier • Optimized for 120 VAC (can be changed) • 15 watt full scale (can be changed) • Uses DVM floating on AC Neutral as display • Requires moderately high level of analog circuit skill • Very inexpensive Find updates at: www.projects.cappels.org Introduction I am doing some work
A Pretty Good Wattmeter For Bench Use using microcontroller using Atmega Read More »
Specifications Input: AC, DC or AC+ DC to > 10 KHz Ranges: 200 mv, 2V, 20V, 200V, 600V full scale Accuracy: ±1%, depending on divider resistor selection Crest Factor: 1 to 3, up to 5 with degraded accuracy Input impedance: 1 Megohm shunted by 20 pf Battery drain < 300 uA Introduction The DVMs in the
TRUE RMS-TO-DC Adapter For DVM using microcontroller using Atmega Read More »
Download: assembler source mhm031002A.asm A milliohmmeter is just the tool for checking trace resistance on a printed circuit board, tracking down shorted traces, and measuring the contact resistance of a switch or connector. Its the kind of tool that would come in real handy occasionally, but not often enough to justify shelling out hundreds of dollars.
A Microcontroller Based Digital Lock-In Milliohmmeter using ATtiny2313 microcontroller Read More »
About This project describes an open software open hardware pH meter using an Arduino/Freeduino board. In other words, this is an electronic circuit to be connected with a glass electrode pH sensor. It was possible by the idea from my friend Mr. Denis Vidal, the space that my supervisor gave me, prof. Dr. Emanuel Carrilho, BioMicS Group, Instituto de Química de São Carlos, Universidade de
PHduino pH Meter Using Arduino Using Atmega Read More »
Encased in a pencil box to keep the point-to-point wiring on the back of the board from shorting to wires and things on the workbench, the plastic case also holds the offset and gain post as well as the input connector and the switches that switch on the near-zero and near-full scale references. I wanted
HF AC Millivoltmeter Adapter using microcontroller using Atmega Read More »
This is a handy companion for a digital voltmeter. Its allowed me to do a lot of things I used to use my oscilloscope for, and in addition it measures voltages to much greater precision.Using an LM324 quad op amp, this peak detector provides 2% measurement accuracy on square waves from 5 Hz to 20
Precision Audio Frequency Peak Detecting Probe using microcontroller using Atmega Read More »
Downloads Download the Download FreePC files in and the detector board layout png file in zipped forma: schottkydedtector080309 Find updates at www.projects.cappels.org Starting to do a little work at 330 MHz, I decided that my existing field strength meters were not adequate for for my needs. The 330 MHz project came to a stop, and I set
