Linear tuning is essential for a wide range of applications requiring frequency precision over time and temperature. The latest series of voltagetuned oscillators from Synergy Microwave (www.synergymwave.com) provide outstanding tuning linearity at frequencies through 10.9 GHz. The first three models in the DCO and DXO families of voltage-tuned oscillators provide frequency coverage of 4730 to 5420 MHz, 8100 to 9000 MHz, and 10,350 to 10,900 MHz with low phase noise and low second harmonics.

The DCO and DXO series oscillators allow fine-grain tuning as a result of tuning sensitivities from 22 to 72 MHz/V. The lowest-frequency member of the new oscillator lines is model DCO473542-5 which operates from 4730 to 5420 MHz. It supplies at least 0 dBm output power across that range, with output power that remains flat with frequency and temperature within about 1.5 dB from 40 to +85C. It uses tuning voltages from 0 to 22 V with tuning sensitivity of 22 to 45 MHz/V.

Measurements of frequency with tuning voltage for the model DCO473542-5 voltage-tuned oscillator, for example, yielded a frequency of approximately 4670 MHz for a 0-V tuning voltage, 4881 MHz for 5-V tuning, 5075 MHz for 10-V tuning, 5295 MHz for 15-V tuning, 5437 MHz for 20-V tuning, and 5470 MHz for 22-V tuning. The phase noise is 8 dBc/Hz offset 10 kHz from the carrier. Model DCO473542-5 is designed for a supply voltage of +5 VDC.

Model DXO810900-10 tunes from 8100 to 9000 MHz with tuning voltages from 0 to 24 V. It delivers at least 0 dBm output power with excellent output-power flatness across frequency and with changes in temperature. It exhibits tuning sensitivity from 18 to 72 MHz/V and boasts phase noise of 78 dBc/Hz offset 10 kHz from the carrier. Model DXO810900-10 is designed for a supply voltage of +10 VDC.

The highest-frequency member of the new linear tuning oscillator families is model DXO10351090-5, which tunes from 10,350 to 10,900 MHz with tuning voltages of 0 to 25 V (see figure). As with the other models, it delivers at least 0 dBm output power across the frequency tuning range. The output power remains flat within 1.5 dB from 40 to +85C. In addition, its tuning sensitivity, which is nominally 30 to 60 MHz/V, remains relatively unchanged with temperature. As with the two lower-frequency voltage-tuned oscillators, model DXO10351090-5 provides excellent rejection of second-harmonic content with second harmonics ranging from 31 dBc or better at the lowest frequencies to better than 40 dBc when evaluated at room temperature (+25C). Model DXO10351090-5 is designed for a supply voltage of +5 VDC. It exhibits phase noise of 80 dBc/Hz offset 10 kHz from the carrier.

The DCO series oscillators are supplied in compact surface-mount packages measuring 0.3 x 0.3 x 0.1 in. Models will be added shortly to extend frequency coverage from 4 to 12 GHz. Synergy Microwave Corp., 201 McLean Blvd., Paterson, NJ 07504; (973) 881-8800, FAX: (973) 881-8361, e-mail: sales@synergymwave.com, Internet: www.synergymwave.com.

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