The UHF-RUB option provides an atomic frequency standard for the UHFLI Lock-in Amplifier. All UHF instruments feature a high-quality temperature controlled crystal oscillator (OCXO). For experiments that require a high frequency accuracy and stable operation over long periods of time (even in adverse environmental conditions), the UHF-RUB option gives access to a rubidium atomic clock with extreme temperature stability, minimal phase noise, and reliable performance through the aging process. Indeed, the option reduces the need for periodic calibration as there is essentially no clock aging.
The clock generated by the UHF-RUB option can be output on the clock connector of the UHF instrument.