EDN

Frequency Counter by PIC16F628

In this project we are building a basic and low cost frequency counter circuit . It can measure from 16Hz to 100Hz signals with a maximum amplitude of 15V. The sensitivity is high, the resolution is 0 ...
Electronic Design

Frequency Quadrupler Enables Low-Frequency Measurements, Spans Up To Four Decades

In frequency counters, the gating time allotted for counting is often too short to resolve low frequencies. A phase-locked loop could be used to multiply the input frequency. But in some cases, the ...
EDN

Programmable Frequency Divider Circuit

The circuit was designed to divide the frequency of a TTL compatible square wave signal which can be programmed with the use of three 7490 to perform the required operation. 7430 – an 8-input NAND ...
Electronic Design

10-GHz Divide-By-100 Prescaler Connects To 100-MHz Counter

The prescaler described here connects to the front end of a 100-MHz frequency counter to extend its coverage range to 10 GHz. The circuit is a far less expensive way to measure frequencies above 100 ...
Hackaday

Do Not Attempt Disassembly: Analog Wizardry In A 1960s Counter

[CuriousMarc] is back with more vintage HP hardware repair. This time it’s the HP 5245L, a digital nixie-display frequency counter from 1963. This unit is old enough to be entirely made of discrete ...