144 MHz - 148 MHz 1500 W <0.1 dB Low Loss Transmitting Band Pass Filter with "N" connectors

2 meter Bandpass Filter BPF uses high Q coils and capacitors with Q more than 4500. Low loss of filter achieved with careful design and adjustment.

Although intention of this filter is to be used as transmitting filter, design allows also to be used as receiving filter before wideband LNA to protect sensitive device from strong out of band signals.

Intended to be used with linear amplifiers up to 1.5 kW output.

Super low insertion loss. Excellent to put before any LNA or protect receiver from HF transmitters in DX expeditions or in multi-multi environment. This BPF will suppress any signals from HF 1.8 - 28 MHz stations, 50-54 MHz, 70 cm - 432 MHz (430 - 440 MHz).

This Filter will also reduce TVI problems or your problems with neighbors with strong RFI from HF, 6 meter or 70 cm transmitters.

Achieved results on a built Bandpass filter

• 1.8MHz = -100 dB
• 3.8MHz = -91 dB
• 7.1MHz = -81 dB
• 14 MHz = - 67 dB
• 21 MHz = -58 dB
• 28 MHz = -51 dB
• 50 MHz = -34 dB
• 54 MHz = -31 dB
• 144 MHz = -0.09 dB
• 145 MHz = -0.086 dB
• 146 MHz = -0.09 dB
• 148 MHz = -0.089 dB

Harmonics and interfering signals

• 288 MHz = -40 dB
• 296 MHz = -37 dB
• 430 MHz = -41 dB
• 432 MHz = -42 dB
• 440 MHz = -44 dB
• 576 MHz = -36 dB
• 720 MHz = -34 dB
• 880 MHz = -33 dB (GSM - Mobile phone)
• 930 MHz = -31 dB (GSM - Mobile phone)
• 960 MHz = -29 dB (GSM - Mobile phone)
• 1296 MHz = -17 dB

These excellent results were achieved by careful selection of components and design of the filter.

Band Pass filter will suppress any harmonic emission from your linear amplifier.