HP – Agilent/ Keysight 53181A

Optimized for RF applications, the single-channel 10 digit/s 53181A measures frequency, period and peak voltage. A digit-blanking function lets you easily eliminate unnecessary digits when you want to read measurements quickly. For higher-frequency measurements, choose an optional second channel that provides measurements up to 1.5, 3, 5, or 12.4 GHz. A self-guided shallow menu makes this counter exceptionally easy to use

RF Frequency Counter, 10 digits/s
One 225 MHz input channel, plus optional second channel up to 12.4 GHz
10 digits/second resolution
GPIB Standard

The Keysight Technologies, Inc. 53131A/132A/181A high-performance counters give you fast, precise frequency measurements at an affordable price. These counters feature an intuitive user interface and one-button access to frequently used functions so you can make accurate measurements quickly and easily. Real-time digital signal processing technology is used to analyze data while simultaneously taking new readings, speeding measurement throughput. The technology, developed for Keysight’s high-end line of modulation domain analyzers, allows the counters to gather more data for each measurement, so you get higher-resolution measurements in a fraction of the time it takes other counters. The 53131A/132A/181A counters offer built-in statistics and math functions so you can scale measurements and simultaneously measure and track average, min/max and standard deviation. Automated limit testing lets you set upper and lower limits for any measurement. An analog display mode lets you see at a glance whether a measurement is within pass/fail limits. The counters flag out-of-limit conditions and can generate an output signal to trigger external devices when a limit is exceeded. For quick access to frequently used tests, a single keystroke recalls up to 20 different stored front-panel set-ups. For computer-controlled systems applications, each counter includes a standard GPIB interface with full SCPI-compatible programmability and a data transfer rate of up to 200 fully formatted measurements per second. The standard RS-232 talk-only interface provides printer support or data transfer to a computer through a terminal-emulation program.
Datasheet