430 - 440 MHz High Selectivity, High Q, Low Loss Bandpass Filter

  • 430 - 440 MHz High Selectivity, High Q, Low Loss Bandpass Filter

430 - 432 - 440 MHz High Selectivity, High Q, Super Low Loss Bandpass Filter

Band-pass Filter BPF uses high Q coils and capacitors with unloaded Q of more than 1500. Low loss of filter is achieved with careful design and adjustment. Best receiving RFI band pass filter designed for 70 cm band.

70cm-432MHz-EME-bandpass-filter-MadeBy-antennas-amplifiers.com


Recording Return Loss - S11 (CH 1) and Insertion Loss - S21 (CH 2) was done with HP8753ES network analyzer.
Calibration is "2 port calibrated" and its always done to ensure maximum precision.

Characteristics of 430 - 432 - 440 MHz Receiving Band pass filter.
Measured data. Here we can see 70 cm band measuring. Attenuation from 430 to 440 MHz is just 0.15 dB! Our return loss for same frequency is -35 dB.

70cm-Low-Loss-Band-Pass-Filter-Measured-Data
 
Detailed attenuation for all important frequencies is presented in next table:

Frequency [MHz] Attenuation [dB]
1.82 MHz > 100 dB
3.8 MHz > 100 dB
7 MHz 100 dB
14 MHz 95
21 MHz 95
28 MHz 81
50 MHz 67
54 MHz 64
88 MHz 51
108 MHz 45
144 MHz 36
146 MHz 36
Band Frequency 430 MHz 0.15 dB; S11 (Return loss): -35 dB
Band Frequency 432 MHz
0.15 dB; S11 (Return loss): -35 dB
Band Frequency 440 MHz
0.15 dB; S11 (Return loss): -35 dB
880 MHz (GSM) 20 dB
960 MHz (GSM) 25 dB
1296 MHz 43 dB

For 430 - 440 MHz Low Loss Band-Pass Filter we are using "N" connector type (Male / Female), but since all filters are custom made, going for other connector types is not an issue. You can always ask by e-mail. For example 70 cm band pass filter with SMA connectors is presented in next picture. Not to get confused, electrical characteristics for both type of connectors are same.

70 cm Low Loss bandpass filer with SMA connectors

More measurements for Receiving 430 - 440 MHz Band-pass filter:

1. Filter characteristics ''zoomed in''. Insertion loss, S21 is set to 0.2 dB per division. Here we can see excellent "flatness" on 70 cm band.

432MHz Bandpass Filter Low Loss Measured Data Zoomed

2. Filter characteristics for HF. Signal is highly suppressed. In some parts even more than 100 dB.

70cm-Low-Loss-Band-Pass-Filter-HF-Attenuation

3. Filter characteristics on FM frequencies and 6 meter band.

430-440MHz-Low-Loss-Band-Pass-Filter-HF-50MHz-88MHz-FM-Attenuation

4. Filter characteristics on UHF frequencies.

432MHz-Super-Low-Loss-Bandpass-Filter-144MHz-GSM-23cm-Attenuation

Positions of connectors are selected so that the filter can be directly connected to the coaxial relay. Band pass filter enclosed in strong 1mm sheet brass box. Strong mechanics will ensure stability and longevity.

For this type of filter almost nothing will disturb noise performance of any wide band pre-amplifier which is especially important in terrestrial and EME communications. It will further ensure smooth operation in the presence of strong signals.
 
You can check out our similar 432 MHz products here:

70cm band, 432 MHz Receiving Bandpass for Ham: 430 - 440 MHz Receiving Band-Pass Filter. 70 cm band.

70cm band, 432 MHz Receiving Outdoor Bandpass: 430 - 440 MHz Receiving Band-Pass Filter made for outdoor. 70 cm band.

70cm band, 432 MHz 1000 W Bandpass for Ham: 430 - 440 MHz 1000 W Band-Pass Filter. 70 cm band.

70cm band, 432 MHz 1500 W Bandpass for Ham: 430 - 440 MHz 1500 W Band-Pass Filter. 70 cm band.

70cm band, 432 MHz 2500 W Bandpass for Ham: 430 - 440 MHz 2500 W Band-pass Filter. 70 cm band.

70cm band, 432 MHz 4000 W Bandpass for Ham: 70 cm 4 kW Low Pass - Notch Filter


We are also making filters on all frequencies and powers. Even if we don't have an offer on our site, we may be able to make it for you. So feel free to contact us.

You might also like to read about our 70 cm band antennas (432 MHz)70 cm High Gain Low Noise Antennas for 432 MHz. Excellent G/T


  • Product Code: 0714
  • Availability: In Stock
  • 89.00€


Tags: 430MHz, 432MHz, 440MHz, 70cm, 0.7meters, UHF, BandPass, RFI, Band-Pass, Filter, BPF, High, Q, Selectivity, Low, Loss, Economical, Receive, Receiving, Field, Day, Ham, Radio