• Rubidium or high stability oven frequency reference standard
• Distribution amplifiers for 5x10 MHz and 1x5 MHz outputs as standard
• Optional 10x10 MHz outputs
• 0.001 ppm aging in 10 years (Rubidium)
• Ideal for telecommunication test systems and calibration laboratories

Ideal Reference for Multiple Testers
Pendulum frequency standards suit the highest demands for stability. All frequency standards offer multiple buffered outputs (5x or 10x outputs of 10 MHz sine). Choose from the low-cost 6688 based on a very-high-stability oven-controlled SC-cut crystal oscillator or the 6689 with a built-in Rubidium atomic clock. These standards are suited for use in automatic test systems, for example in the production department of telecommunications companies, especially when multiple instruments/testers need to be supplied with a stable frequency reference. The very short warm-up time of only 10 minutes makes these units suitable also for field use.  

• Up to 11 other instruments can be supplied
• Both 10 and 5 MHz always included
• Portable ultra-stable Rubidium standard takes the stability to any desired location