一、Characteristics
Cavity band-stop filter is divided into cavity band-stop filter,LC band-stop filter and active band-stop filter circuit. The structure is made up of the whole metal cutting, cavity polishing and coating. With high processing accuracy, solid structure, high reliability, high-end parasitic passband is far, frequency range is 0.5-18GHz, input/output 50Ω impedance matching, input/output can be used interchangeably, easy to cascade use; Stable and reliable performance in the full temperature range, meeting the requirements of military working environment (-55℃ ~ +85℃); High near-end suppression, good phase consistency, small volume, moderate Q value, small standing wave, flat in-band amplitude frequency characteristics, small insertion loss, high out-of-band suppression, and can meet the continuous impact of 20 grams within 11 milliseconds, can meet the frequency of 10 ~ 2000Hz 10 grams of continuous vibration; The storage temperature range is -65℃~+125℃, the maximum input power is 50W, and the relative humidity is 0 ~95%.

Cavity band-stop filter
二、Model & Electrical characteristics
| Metal cavity band-stop filter (BSF bandpass filter or notch) model and parameter table |
| Part No | Band-stop frequency (MHz) | Band-stop Attenuation(dB) | Passband frequency (MHz) | Passband loss(dB) | Size(mm) |
| BSF450~20 | 440-460 | 28 | DC~420 | 480~1500 | 1.5 | 274*130*56 |
| BSF504~30 | 489-519 | 40 | 394~463 | 566~840 | 2.0 | 419*110*70 |
| BSF837~25 | 824-849 | 30 | 700~814 | 861~2000 | 3.0 | 224*57.5*52 |
| BSF882~25 | 869-894 | 50 | DC~875 | 906~2500 | 1.5 | 420*114*40 |
| BSF875~10 | 870-880 | 60 | 600~860 | 885~1150 | 3.0 | 180*92*63 |
| BSF899~6 | 896-902 | 30 | 700~889 | 907~2000 | 3.0 | 180*59.5*45.5 |
| BSF943~35 | 925-960 | 40 | DC~915 | 970~2500 | 2.0 | 420*114*40 |
| BSF945~30 | 930-960 | 30 | 620~910 | 980~3000 | 2.0 | 199*55*49 |
| BSF943~25 | 935-960 | 60 | 600~915 | 980~1150 | 1.0 | 312*48*63 |
| BSF1583~45 | 1560-1605 | 40 | 800~1500 | 1655~4000 | 2.0 | 238*53*34 |
| BSF1843~75 | 1805-1880 | 50 | DC~1785 | 1900~3300 | 1.5 | 398*78*40 |
| BSF1844~72 | 1808-1880 | 40 | 1450~1785 | 1900~2430 | 3.0 | 224*92*47 |
| BSF1860~100 | 1810-1910 | 30 | 1000~1700 | 1980~2200 | 2.0 | 240*35*43 |
| BSF1900~40 | 1880-1920 | 55 | DC~1860 | 1940~3000 | 1.5 | 143*79*49 |
| BSF1950~60 | 1920-1980 | 55 | DC~1895 | 2005~3000 | 1.5 | 143*79*49 |
| BSF1960~60 | 1930-1990 | 50 | DC~1915 | 2005~4000 | 2.3 | 258*78*40 |
| BSF2018~15A | 2010-2025 | 60 | 1450~1980 | 2055~2400 | 1.0 | 172*35*32 |
| BSF2018~15B | 2010-2025 | 55 | DC~1990 | 2045~3000 | 1.5 | 143*79*49 |
| BSF2140~60A | 2110-2170 | 50 | DC~2095 | 2185~3600 | 2.0 | 258*66*40 |
| BSF2140~60B | 2110-2170 | 55 | DC~2085 | 2195~3600 | 1.5 | 143*79*49 |
| BSF4535~330 | 4370-4700 | 50 | DC~4000 | 5050~6000 | 1.0 | 138*40*29 |
| Note: Due to many product models, only some representative models are listed in the table |
三、Application & attention
The cavity band-stop filter is used to suppress the useless signals and noise outside the band, so that the electromagnetic spectrum can be selected and allocated according to the application, and can also limit the high-power transmitter to transmit signals in the specified frequency band, prevent the receiver from interference outside the working band, and have a better frequency selection effect in the electronic and electronic high-frequency system. Pay attention to the good grounding of the shell when using, otherwise it will affect the out-of-band suppression and flatness index. Cavity band-stop filters are commonly used in aviation, aerospace, communications, electronic countermeasures, radar, radio and television and various electronic test equipment.
The metal cavity band-block filter is a product with strong customization, and the indicators are associated with each other and are known as "affecting the whole body". Therefore, the user needs to clearly state the indicator requirements before customization. Once the product is made, it cannot be changed. If there are indicators that exceed the physical limit of the material itself, the best indicators can be achieved through negotiation between the two parties. The company can customize cavity filter, cavity high-pass filter, cavity low-pass filter, cavity band-stop filter, cavity band-pass filter.