EIP Model 351D Autohet  Microwave Frequency Counter *Option 3: 5x10^-9 Oscillator Frequency Range: 20 Hz to 12.4 GHz, 18 GHz, 20 GHz -30 dBm Sensitivity  +33 dBm (2 Watt) Overload Protection  40 MHz to 200 MHz FM Tolerance Mustiple Signal Discrimination 1 Hz Resolution in 1 Sec  11 Digit Sectionalized LED Display  Plug-in Exchange Board Construction ** WE BUY VINTAGE HP TEST EQUIPMENT — ANY CONDITION ** Please message us if you have test equipment, circuit boards, or manuals that you would be interested in selling. Thank you for visiting TreyTechUS! Over 50,000 manuals, books, and items in stock. Our inventory is always growing. TreyTechUS sells all types of technical manuals and hard-to-find user & service information. Acquired over the past 40 years! WE SHIP WORLDWIDE.