Notch Filters for CATV / MATV / RF / FM Systems

Fixed and Tunable Models (0.8 to 1000 MHz)

Select A Category ... Off-Air/RF FM CATV General Description Table & Graphs Specifying Your Notch

Notch Trap Models

FM Notches

• Center frequency can be specified from 88 to 108 MHz
• Sharp, ultrasharp, fixed frequency and tuneable frequency models are available
• Bandwidth for VHF/FM (10-250 MHz) or VHF/UHF systems (5/400-800 MHz)
• Filter Impedance is available for 75 ohms (F, BNC) or 50 ohms (BNC, N)
• Multiple notch models for FM band deletion are available: customized for exact spectrum deletion and to preserve signals, e.g., attenuate 88-108 MHz, pass 109.25 and above (Marine Navigation band)
• Custom-made FM multiple notches for specified FM carriers are also available

VR7-(Fo) HQ Series

Tunable VHF/CATV/FM Trap

Frequency tunable - suppress one frequency (Fo) using two adjustable trimmers

• Six models covering: VHF low, VHF high, FM, CATV Mid1, CATV Mid2, CATV Super
• Rejection: > 40 dB at Fo

• Selectivity Examples:
  • 3 dB BW: ± 1.5 MHz (Fo < 200 MHz)
  • 3 dB BW: ± 2.5 MHz (Fo < 300 MHz)
• Bandwidth: 5-550 / 10-750 / 40-860 MHz
• Fo: Factory-preset; field tunable via two trimmers
• Rejection: Individual notches are approximately 8 dB

Back to the top

Sharp FM Frequency Notches: (Fixed & Tuneable)

FM Notches (75 ohms, F-connectors, Optional 50 ohms - BNC or N connectors)

FM notch filters are available with five levels of selectivity. Designed to suppress one FM frequency and pass all other signals with low to minimal loss to adjacent carriers. The notches apply for user-specified FM frequencies (Fo).

CR7- (Fo) HQ (25) - 25 dB Fixed Notch

• Attenuation: 25 dB or less (see graph)
• Selectivity: 3dB bandwidth is ± 0.5 MHz
• Bandwidth (MHz): 40 - 220 / 8 - 560 / 10 - 860

CR7- (Fo) HQ (50) > 50 dB Fixed Notch

• Attenuation: > 50 dB attn
• Selectivity: 3dB bandwidth is ±1.25 MHz.
• Bandwidth: 50 to 220 MHz, or 8 to 550 / 750 MHz.

CR7- (Fo) HT >30 dB Sharp Fixed Notch

• Attenuation: > 25 dB
• Selectivity: 3 dB bandwidth is ± 0.25 MHz
• Bandwidth: 50 to 220 MHz

VR7-FM - Tunable FM Notch

• Consists of two tuneable 8 dB notches
• Combined attenuation: > 40 dB
• Selectivity: 3dB bandwidth is ± 1.5 MHz
• Bandwidth: 50 to 220 MHz or 8 to 550 / 750 MHz

Example Graphs

CR7-88.6 HQ (25) and Order info

Back to the top

VR7-FM HT - Sharp, Tuneable FM Notch

• Sharp and Tuneable FM filter with 88 to 108 MHz tuning range
• Attenuation: User-specified (from 20 to 40 dB)
• Fo is tuneable via two trimmers
• Example selectivities:
  • 25 dB notch: 3dB bandwidth is ± 0.35
  • 40 dB notch: 3dB bandwidth is ± 0.75
• Bandwidth: 50 to 250 MHz

Example Graphs:

VR7-FM HT 95

VR7-FM HQT - Ultra-sharp, Tuneable FM Notch

• Ultra-sharp notch
• Tuneable from 88 to 108 MHz
• Optimal range is ± 2 MHz
• Attenuation: User-specified (from 20 to 40 dB)
• Example selectivities:
  • 20 dB notch: 3dB bandwidth is ± 0.1 MHz
  • 40 dB notch: 3dB bandwidth is ± 0.2 MHz
• Bandwidth: 50 to 200 MHz

Example Graphs:

VR7-HQT 99

BR7-(F1, F2 ... Fn) HQ

Custom Multiple Frequency Notches

Multiple Frequency Notches in single enclosure

• Fo (< 350 MHz): up to seven notches
• Fo (< 650 MHz): up to five notches
• Rejection: >40 dB
• Bandwidth: varies with notch tuning
• Dimensions (in): 1.75 x 19 x 4 (rack or wall mount)
• Multiple notches can be consolidated at one centre frequency for a wider notch bandwidth of 1 to 4 MHz
• Example applications: multiple FM interference notches, Multiple channel negative traps.

Back to the top