computer hardware, electronic components, consumer electronics  
Frequency counters are digital instruments which measure the frequency of an input signal. A frequency counter displays numerically the frequency of the signal applied to its input. The frequency is typically determined by counting the number of times the oscillating signal crosses some voltage, usually a zero volt reference, during some precise time interval. Typically, the input signal operates a digital counter. The input signal is normally conditioned by known input circuitry, such as a Schmitt trigger circuit, which receives an input signal and outputs one pulse per cycle of input. Frequency counters generally employ a crystal oscillator for generating a reference frequency against which the frequency of the input signal is compared. A crystal controlled frequency counter typically comprises a piezoelectric oscillator, a digital counter, an output display, and selected input, output and internal interface circuits.

Listings on RF and microwave electronics : Frequency counters

  • Laurel Electronics, Inc.
    Designs, manufactures and sells frequency & rate meters, digital counters, digital and analog totalizers, ratio & draw meters, batch controllers, digital timers, phase angle meter, duty cycle meter, quadrature position & rate meter, linearizing panel meter, large-digit counters & timers, DC voltmeter & ammeter, process meter, strain, load cell & microvolt meters, scale / weight meter, true AC RMS voltmeter & ammeter, temperature meter / controller, low-cost meters, 1/8 DIN bargraph process display, loop-powered digital panel meter, microminiature digital process meter, large-digit meters, 1/8 DIN serial input meters / controllers, large-digit remote displays, large bargraph process display, datalogging software, sealed enclosures & covers, bench-style cases, rotary signal selector switches, triple-output loop retransmitter, and parallel BCD to serial converter. USA.

    http://www.laurels.com
  • Pendulum Instruments AB
    Manufacturer of frequency counters, modulation domain analyzer, microwave counters, spectrum monitor/analyzer, microwave antenna path alignment test set, frequency references, frequency distribution systems and time synchronization testers for telecom and the electronic industry. Sweden.

    http://www.pendulum-instruments.com
  • Precision Test Systems
    Designer, manufacturer and supplier of electronic test and measurement equipment, including data acquisition system, digital multimeters, distribution amplifiers, frequency counters, field strength meters / analyzers, frequency / time standards, GSM / wireless products, GPS amplifiers / splitters, oscilloscopes, radio system analyzer, signal generators, and spectrum analyzers. UK.

    http://www.ptsyst.com
  • Stanford Research Systems, Inc.
    Manufacturer of small instrumentation modules, lock-in amplifiers, optical chopper, preamplifiers, digital delay generators, high voltage power supplies, gated integrators and boxcar averagers, photon counter, frequency standards/oscillators, time interval and frequency counters, synthesized clock generator, synthesized function generators, FFT spectrum analyzers, LCR meters, thermocouple monitor, dual channel programmable filters, melting point apparatus, quartz crystal microbalances, nitrogen laser, ion gauge controller, residual gas analyzers, and high pressure sampling systems. USA.

    http://www.thinksrs.com
  • Thurlby Thandar Instruments Limited
    Manufacturer of electronic test equipment including DC power supplies, laboratory power supply, system power supplies, ac power supplies programmable power supply, function generators, arbitrary generator, pulse generators, RF signal generator, digital multimeters, LCR meter, DC electronic load, frequency counters, counter timer, harmonic analysers, (harmonic analyzers), EMC test equipment, logic analysers, (logic analyzers), and data analysis instruments. UK.

    http://www.tti-test.com

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2009 Electronics manufacturers directory • (Frequency counters section) • Site map