Long Practical Expirience of Large Scale Quantity Manufacturing of E-10 Stability DOCXOs and the Futher Development of Subject Concept

During last 10 years the mobile phone networks are being widely spread. Accordingly the market for base stations\´ equipment has been drastically increased. This phenomenon became one of the key driving forces for pushing development of OCXOs technology. One of the most critical components of base station equipment for the networks of CDMA-"family" is an ultra-precision crystal oscillator meeting following key requirements for frequency stability: (1... 2)E-10 vs. operating temperature, lE-10/day, and 2E-8/year. In year 2000 the appropriate model of double-oven oscillator (DOCXO) -MV89 -was developed, and from 2001 Morion has started with large scale quantity manufacturing of those. Actually there is a very tight combination of top technical requirements and large scale quantity manufacturing with acceptable costs. To overcome the certain difficulties all critical stages of subject technology, i.e. starting from SC-cut contoured blank, then crystal, then DOCXO itself and its testing, were reworked with significant improvements. About 50,000 units of subject DOCXOs were manufactured and delivered. Now this line is still in good shape providing up to 500 units weekly. The important issues of large scale quantity manufacturing technology are being highlighted combined with statistical analysis of main production DOCXOs parameters. Large collected Data Base is being used as fundament for reasonable conclusions. At the end the further developments of DOCXOs technology are being presented. There are designs and technical data of low profile (17 mm height), and miniature (36 times27 times 19 mm) DOCXOs\´ models. Their technical data are very close to those achieved for original "large" model (2"times2"times1.5") being amain subject of the paper, i.e. (1...2)E-10 vs. operating temperature -20...+70degC and (2...3)E-8/year. The serial manufacturing of both a.m. new DOCXOs\´ models has been already successfully started.