{"id":3101,"date":"2025-01-27T01:47:21","date_gmt":"2025-01-27T00:47:21","guid":{"rendered":"https:\/\/ha3ln.hu\/?p=3101"},"modified":"2025-04-13T14:20:05","modified_gmt":"2025-04-13T12:20:05","slug":"rx-bpf-project","status":"publish","type":"post","link":"https:\/\/ha3ln.hu\/?p=3101","title":{"rendered":"RX BPF Project"},"content":{"rendered":"

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Making sure that during the SO2R\/2BSIQ operations the adjacent radios will not damage each other’s input decided to build RX band-pass filters for both RX paths. Excellent solution was found on RemoteQTH page. Aiming to reach the high attenuation level two units were built back-to-back. However I played a lot with the fine tuning could not really reach better insertion loss values. On 40m the passband transmission loss is even peaking at 4+dB which acts like an attenuator right a way. The 80m and 160m is significantly better. However the high TL was not perceived during the contests compensating the path loss a pre-amp is planned.<\/p>\n

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Inspirations:<\/h3>\n