HP 5381A / Agilent 5381A 80 MHz Frequency Counter with 7-Digit Display

<p>Frequency Range: 10 Hz to 80 MHz
Sensitivity: 25 mV rms - 30 Hz to 20 MHz, 50 mV rms - 10 Hz to 80 MHz
Input Impedance: 1 Mohm, &lt;50 pF
Input Attenuation: X 1, X 10, X 100
Gate Time: 0.1 second, 1 second &amp; 10 Seconds.
Looks very similar to 5383A below</p>