5720 Quad-Notch Filter
The Netcom 5720 is a UHF quad-notch filter built from four independent lumped element notch filters in series. Each notch covers its own quarter of the band: notch 1 from 225 to 299.9 MHz, notch 2 from 300 to 374.9 MHz, notch 3 from 375 to 449.9 MHz and notch 4 from 450 to 512 MHz. Each is tuned in 100 kHz steps and set on its own, so you place the notches wherever the interferers happen to be.
Rejection is 15 dB minimum at the notch centre, held across ±2 MHz. Insertion loss is 5 dB maximum at 10 MHz from a notch and 3.5 dB maximum beyond 24 MHz. Each notch switches in under 50 microseconds.
IIP3 is +54 dBm, which is high, and it is the number that matters most in this product. A notch filter is there because strong signals are present, so the filter itself has to stay linear under them. Control is by SPI serial interface. The unit runs from 3.3 VDC at 45 mA, handles +25 dBm, has a 2.5:1 VSWR, measures 1.70 x 1.80 x 0.35 inches and works from -40 to +85 °C.
- Specifications
- Performance
- Mechanical
- More Details
| Frequency Range | 225 to 512MHz |
| Notch 1 Frequency Range | 225 – 299.9MHz |
| Notch 2 Frequency Range | 300 – 374.9MHz |
| Notch 3 Frequency Range | 375 – 449.9MHz |
| Notch 4 Frequency Range | 450 – 512MHz |
| Notch Rejection at ±2MHz | 15dB min |
| Passband Insertion Loss (beyond ±24MHz) | 3.5dB max * |
| Insertion Loss at ±10MHz | 5dB max * |
| Impedance (Input/Output) | 50 Ω |
| VSWR | 2.5:1 |
| Temperature Range | -40°C to +85°C |
| RF Power Handling | +25dBm |
| IIP3 | 54dBm |
| DC Power | |
| DC Voltage | 3.3 VDC ±0.3 VDC |
| DC Current Max | 45mA |
| Control Interface | SPI Serial Input |
| Tuning Resolution | 100KHz |
| Switching Speed, 90% RF Power (typical) | < 50μsec |
| Dimensions [L x W x H] | 1.70 X 1.80 X 0.35 inches
43.20 X 45.20 X 8.90 mm |
