2 meter 144 MHz – 146 MHz 200 W Transmit – Receive Low Loss Narrow Bandpass Filter

Intended for use with transceivers and transverters up to 200 W output, or before any wide band low noise amplifier (LNA) to protect from any out-of-band signals. Bandpass filter BPF uses high Q coils as well as high Q capacitors. Low loss of filter is achieved with careful design and adjustment.

This filter is equally good as a transmitting and receiving low-loss filter (0.25 dB). 

The filter will reduce the TVI problem or your problem with neighbors with strong HF, 6 m, or 70 cm transmitters.

 

 

Achieved results on a built Band-pass filter:
Suppression – Insertion loss (S21): 
1.8 MHz = -106 dB
3.8 MHz = -110 dB
7.1 MHz = -110 dB
14.1MHz = -105 dB
21.2MHz = -101 dB
28.4MHz = -94 dB
50 MHz = -76 dB
52 MHz = -75 dB
54 MHz = -73 dB
70 MHz = -64 dB
70.5 MHz= -64 dB
88 MHz = -53 dB
98 MHz = -46 dB
108 MHz = -39 dB
144 – 146 MHz = –0.25 dB
288 MHz = – 60 dB
432.1 MHz = – 36 dB
440 MHz = – 44 dB

Maximum power input at SWR:
1:1 = 200 W; 1:1.5 = 140 W; 1:2 = 90 W; 1:3 = 70 W (Intermittence 50%)
Measured Return Loss (S11) and Insertion Loss (S21). Characteristics of 144 – 146 MHz 200 W Band pass filter:

2m 200W Transmit – Receive Low Loss Narrow Bandpass Filter

1. HF Suppression for 144 – 146 MHz 200 W Band-pass filter:

 

2. Suppression on 50 MHz (6 Meter band) for 144 – 146 MHz 200 W Band-pass filter:

 

 

3. Suppression on 70 MHz (4 Meter band) as well as FM frequencies for 144 – 146 MHz 200 W Band-pass filter:

 

 

4. Zoomed characteristics:

 

 

5. Suppression on Harmonic and 70 cm band. Attenuation on 288 MHz harmonic is more than 60 dB and 432 – 440 MHz attenuation is from 36 to 44 dB.

 

 

200 W transmitting and receiving band-pass filter could be used for outdoor mounting—price difference 8 EUR (plastic box “DB” and two brackets).

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