For the circuits under consideration as the frequency values of the reference
quartz oscillator were used [f.sub.RO] = 100 MHz for the three values of the output frequency of the VCO of hybrid synthesizer [f.sub.FS] = 500, 2000, and 3500 MHz.
The next obstacle faced by Lyons and his group was to develop a method to automatically adjust the
quartz oscillator frequency until it matched the frequency of the ammonia absorption line.
The master synthesizer generates a sinusoidal signal with the frequency of [[omega].sub.IF] + [[omega].sub.D], where [[omega].sub.D] is the driving frequency and it is set to be close to the resonance frequency of the
quartz oscillator. The outputs from the two synthesizers enter the first multiplier and the driving-frequency signal with the frequency [[omega].sub.D] is produced by the following low-pass filter.
Where a separately bonded resonator is used, package size is comparable to the smallest
quartz oscillators, and the cost is similar if not lower.
Despite these advantages, manufacturers can't afford to take for granted the likelihood that
quartz oscillators will go the way of the vacuum tube--they are a proven technology and have been for the last 50 years.
This remained true in the early days of
quartz oscillators. However, as
quartz oscillator technology continued to improve, it became evident that HF radio was limiting the accuracy of the frequency and time signals being delivered.
In the last decade, micro-electromechanical systems (MEMS) oscillators began replacing
quartz oscillators in many applications, including high-reliability automotive applications [4].
Frequency's Morion affiliate supplies high-quality, cost effective
quartz oscillators and components.
Tokyo, Japan, Nov 17, 2005 - (JCNN) - Epson Toyocom has commercialized its TSU series of high precision pressure measurement sensors with
quartz oscillators, and starts shipment in sample quantities for 400,000 yen ($3,400) per unit from late November.
Frequency's Morion affiliate supplies high-quality, cost-effective
quartz oscillators and components.
The early SiTime products will replace
quartz oscillators in fit and function, later the full advantages of the MEMS technology will be brought to bear.