BKPRECISION 1856D Multifunction Counter

Range 0.1 Hz - 3.5 GHz
Frequency: yes
Totalize: yes
Period: yes
Time Base Stability: ±1ppm
Best Resolution: 1 nHz
No. of Digits: 9
Display Hold: yes
Low Pass Filter: yes
Sensitivity: 
 30 mV (0.1 Hz - 100 MHz), 
 15 mV (80 MHz - 2 GHz), 
 20 mV (2 GHz - 3.0 GHz), 
 30 mV (3.0 GHz - 3.2 GHz), 
 50 mV (3.2 GHz - 3.5 GHz), 
Remote Interface: RS232
Self-Test: yes
Input Power: 115/230 V (50/60 Hz)
Weight: 5.5 lbs (2.5 kg)
Dimensions: 239 x 89 x 269 mm

Datasheet