Frequency Offset Generators

Concepts

• teddington
• precision equipment
• frequency offset generators
• up to 12 frequency offset generators
• generators
• frequency
• offset
• laboratory and optical equipment
• spares
• all sites

Location

Teddington

Description

Provision of up to 12 Frequency Offset Generators to be used in RETSI at Sites 3 & 4, and for the provision of spares to support all sites.

Award Detail

CPV Codes

• 38000000 - Laboratory, optical and precision equipments (excl. glasses)

Indicators

Legal Justification

NPL requires a number of high-performance frequency offset generators under the National Timing Centre programme, one for use with each active hydrogen maser that will be purchased through the programme. The frequency offset generator required should accept a reference sine wave signal at 10 MHz or 100 MHz, and generate similar output signals with a programmable fractional frequency offset from the input signal at 10 MHz and 100 MHz. A TTL output signal at 1 PPS is also highly desirable. A minimum of two outputs should be available for each signal type, and five would be preferred. The primary performance requirement is that the output signals from the frequency offset generator should (as far as possible) not add any noise to the input signal. In other words, the phase noise of the output signals between 1 Hz and 10 kHz should match that of the signals produced by an active hydrogen maser with high-quality local oscillator (low phase noise option). Similarly, the instability of the output signals at averaging times from 1 s to 1 day should be no greater than the instability of the signals generated at that frequency by an active hydrogen maser. The only commercially-available frequency offset generator identified by NPL that meets the requirements specified above is the model EOG-2020 produced by SKK Electronics. A number of the units are already in use within the current NTC R&D programme, the same model should be used for continuity and seamless system integration – selection of a different unit type would create significant work to update baselined design documents and written software.