2-meter Receiving Budget Band-Pass Filter with high selectivity

Low loss of filter achieved by careful design and adjustments.

Electrical Specifications:

Frequency range: 144 – 148 MHz
Insertion Loss: < 0.4 dB
Input return loss: < – 20 dB
Nominal Impedance: 50 Ohm
Connectors: “N”

Attenuation of the nearest band:

1.8 MHz: -97 dB
3.5 MHz: -85 dB
7.1 MHz: -75 dB
14.15 MHz: -63 dB
21.2 MHz: -58 dB
28.4 MHz: -54 dB
50 MHz: -46 dB
54 MHz: -45 dB
70 MHz: -40 dB
70.5 MHz: -40 dB
88 MHz: -35 dB
98 MHz: -31 dB
108 MHz: -27 dB
144 MHz: 0.36 dB, RL = – 24 dB
146 MHz: 0.37 dB, RL = – 24 dB
148 MHz: 0.38 dB, RL = – 24 dB
288 MHz: -44 dB
432.1 MHz: -49 dB
1296 MHz: -41 dB

Metal box size: 85 mm x 50 mm x 40 mm.

Measurements: The recorded data on the assembled filter with HP8753ES full 2-port calibrated are presented.

1. Attenuation curves.

 

 

2. HF attenuation on a 2-meter bandpass filter.

 

 

3. Attenuation on 50 MHz and 70 MHz for 144 MHz Budget Band-pass filter.

 

 

4. FM attenuation on 144 – 148 MHz bandpass filter.

 

 

5. Harmonic attenuation (suppression).

 

 

6. Flatness of 2m band-pass filter. S21 (Attenuation) is set to 0.5dB per div! The next graph shows excellent flatness across the whole 2-meter band.

 

 

Feel free to send e-mail if you need something more specific.

All band-pass filters are here: HF, VHF, and UHF Band-Pass Filters

Direct link to all 2-meter filters. We have 50 W, 100 W, 200 W, 300 W, 1500 W and 4000 W versions: 2 Meter Band-Pass Filters