| 2289 |
| Keysight | 53210A | Frequency Counter | 350 MHz RF Frequency Counter, 10 digits/s |
| 2290 |
| Keysight | 53220A | Frequency Counter | 350 MHz Universal Frequency Counter/Timer, 12 digits/s, 100 ps |
| 2291 |
| Keysight | 53230A | Frequency Counter | 350 MHz Universal Frequency Counter/Timer, 12 digits/s, 20 ps |
| 2292 |
| Keysight | 53131A | Frequency Counter | 225 MHz Universal Frequency Counter/Timer |
| 2293 |
| Keysight | 53132A | Frequency Counter | Universal Frequency Counter, 12 digits/s |
| 2294 |
| Keysight | 53181A | Frequency Counter | RF Frequency Counter, 10 digits/s 225MHz
|
| 2295 |
| Keysight | 53150A | Frequency Counter | CW Microwave Frequency Counter, 20 GHz |
| 2296 |
| Keysight | 53151A | Frequency Counter | CW Microwave Frequency Counter, 26.5 GHz |
| 2297 |
| Keysight | 53152A | Frequency Counter | CW Microwave Frequency Counter, 46 GHz |
| 2298 |
| Keysight | Z2090B-170 | Frequency Counter | Pulse Analyzer System for RADAR |
| 2611 |
| Tektronix | FCA3000 | Frequency Counter | Frequency Counter, 300 MHz |
| 2612 |
| Tektronix | FCA3003 | Frequency Counter | Frequency Counter, 3 GHz |
| 2613 |
| Tektronix | FCA3100 | Frequency Counter | Frequency Counter, 300 MHz |
| 2614 |
| Tektronix | FCA3103 | Frequency Counter | Frequency Counter, 3 GHz |
| 2615 |
| Tektronix | FCA3020 | Frequency Counter | Frequency Counter, 20 GHz |
| 2616 |
| Tektronix | FCA3120 | Frequency Counter | Frequency Counter, 20 GHz |
| 3806 |
| GW Instek | GFC-8010H | Frequency Counter | 120MHz Digital Frequency Counter |
| 3807 |
| GW Instek | GFC-8270H | Frequency Counter | 2.7GHz Intelligent Counter |
| 3808 |
| GW Instek | GFC-8131H | Frequency Counter | 1.3GHz Intelligent Counter |
| 7027 |
| Stanford Research | SR620 | Frequency Counter | Time Interval/Frequency Counter, 1.3 GHz |
| 7028 |
| Stanford Research | SR625 | Frequency Counter | Frequency Counter with Rb Timebase, 2 GHz |
| 7029 |
| Stanford Research | FS740 | Frequency Counter | GPS/GNSS Time and Frequency System, 10 MHz |
| 8481 |
| Berkely Nucleonics | 1105 | Frequency Counter | 400MHz Freq. Counter |
| 9524 |
| Keysight | 5342A | Frequency Counter | Keysight 5342A Frequency Counter, 10Hz to 18GHz |
| 9525 |
| Keysight | 5343A | Frequency Counter | Keysight 5343A Frequency Counter, 10 Hz to 26.5 GHz |
| 9988 |
| Keysight | 5340A | Frequency Counter | Keysight 5340A Frequency Counter, 10 Hz to 18 GHz |
| 9989 |
| Keysight | 5352B | Frequency Counter | Keysight 5352B 40GHz Frequency Counter |
| 10030 |
| Keysight | 5361B | Frequency Counter | Keysight 5361B Pulse/CW Microwave Frequency Counter, 20GHz |