Product Feature

A Low Cost Oscillator for Fiber-optic Applications

A new, low cost oscillator has been introduced for use in synchronous optical network (SONET/SDH) OC-192 applications. The new frequency source utilizes an ultra-low noise active device technology that allows the oscillator to achieve very low overall phase noise performance. The oscillator incorporates a low dielectric constant resonator material that provides a very high loaded quality factor (Q) that results in excellent frequency stability and phase noise over temperature.

Fig.1 Typical phase noise.

The model 10-656-9200 voltage-tuned oscillator operates at 9953.28 MHz with an output power of -2 to +4 dBm. Short-term frequency stability is +/-400 ppm over a temperature range of 0° to +70°C with a set on accuracy of +/-200 ppm at room temperature.

The oscillator features an electronic tuning range of 20 MHz from a -5 to +5 V DC tuning voltage and features an output buffer amplifier for superior load pulling characteristics. Frequency pulling is 200 kHz into an SWR of 2 through all phases and frequency pushing is 20 kHz/V. Harmonic outputs are -70 dBc and non-harmonic and spurious outputs are -70 dBc as well.

Among its outstanding performance characteristics is a very low phase noise. Figure 1 shows the oscillator's typical phase noise characteristics over a frequency offset of 100 Hz to 1 MHz from the 9.953 GHz carrier.

The 10-656-9200 oscillator operates from -12 and +12 V DC supplies at an operating current of 25 and 175 mA, respectively. It is housed in a 2" x 2" x 0.5" surface-mount package with an SMA RF output connector and a 4-pin DC interface connector. Figure 2 shows the package outline.

Fig. 2 Package outline.

Applications for the new oscillator include use in SONET/SDH, as a clock recovery phase-locked loop component and in clock timing applications. Higher frequency models are also available for forward error correction applications. Additional information may be obtained via e-mail at

TRAK Microwave Corp., Tampa, FL (813) 901-7200,
Circle No. 302