BPFs: 1015204080160

Please, see 40M High Power BPF made in a smaller enclosure.

Recommended Band Pass filter applied power with antenna VSWR <1.5:

  • 100 CFM fan installed – 3000W CW/SSB (2500W RTTY) 
  • 50 CFM fan installed – 1500W CW/SSB/RTTY
  • Without fan installed – 1000W 

Enclosure is Hammond 1411ZU :

  • Without Fan – 17 x 4″x 5″ (42.5 x 10.5 x 12.5 cm)
  •  With Fan Installed –  18″x 4″x 5″ (46 x 10.5 x 12.5 cm)

hp_40m

In general, schematics is the 5th order Chebyshev inductor-coupled BPF.

  • Insertion Loss < 0.32 dB
  • Band Isolation ( 80M > 60dB, 20M > 70dB, 15M >100dB)
  • VSWR < 1.1 (RL > 26 dB)

40m_bpf

VSWR and Insertion Loss inside the 40M band:

40_bpf_inband

Doorknob capacitors used allow to use it up to 4500-5000 PEP output power but I was able to test it with 3000 watts.

On a picture below you can see 40 and 80 meter band BPFs. 80M BPF box twice deeper than all other band BPF boxes.

VE5MX_40_80 006