The 7D series crystal filter is an electronic filter that uses our high-performance quartz crystals as its resonators. Due to the exceptionally stable physical and chemical properties of our quartz crystals, this selective filter possesses a very high Q factor which is usually over 10,000.
1. Narrow bandwidth: For a crystal filter, its bandwidth is only several thousandth parts of relative bandwidth.
2. Low insertion loss: 3~6dB is achievable for common products.
3. Low rectangular coefficient: The transition band is steep, so the rectangular coefficient is 2 or even lower.
4. Good temperature stability: Our bandpass filter exhibits similar temperature stability to that of quartz crystal.
Based on the abovementioned properties, our quartz crystal filter has found a great many of uses for both civilian and military electrical appliances, such as interphone, cordless phone, communication system, astronavigation system, pilot carrier, etc. In particular, our product plays an irreplaceable role in intermediate frequency applications.
Technical Data of 7D Series Crystal Filter
1. Center frequency: 10.7MHz, 21.4MHz, 21.5MHz, 45MHz, etc.
2. Oscillation mode: Fundamental/3rd overtone
3. Insertion loss: 1.5dB~4.0dB
4. Stopband width (KHz/dB): ±12.5/10, ±18/20, ±25/40
5. Frequency stability: ±10ppm~±50ppm, or customized
6. Attenuation (dB/KHz): 35/300~+1.000, etc.
7. Shunt capacitance (C0): 5pF (max.)
8. ESR: 40Ω~180Ω
9. Package: HC49U, UM-1, UM-5, HC49U×2