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--- lora:868filters [2026/03/07 21:13] – g5rkt
+++ lora:868filters [2026/03/07 22:08] (current) – [£62 868MHz helical cavity filter] g5rkt
@@ Line 5: / Line 5: @@
 {{:lora:lora:hbi-nofilter.jpg?600|}}\\
-And strong adjacent signals we have, plenty of them. Television, 4G, and of course plenty of IR-2030 86xMHz traffic.
+And strong adjacent signals we have, plenty of them. Television, 4G, and unfortunately some very loud IR-2030 86xMHz traffic.
 Of course, Aliexpress to the rescue - plenty of things to try for comparatively little money.
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 {{:lora:cavity-s21.jpg?600|}}\\
-Markers 1-4 are the four frequencies which we would like to reject, pulled down to -15dB to -35dB. Not too shabby! S11 is -33dB, S21 is -2.4dB so we have a filter which we can compare directly to the SAW filter currently on site.
+After some very careful fine-tuning markers 1-4, the frequencies which we would like to reject, were down to -15dB to -35dB. Not too shabby! S11 is -33dB, S21 is -2.4dB so we have a filter which we can compare directly to the SAW filter currently on site.
 {{:lora:finished_cavity.jpeg?600|}}\\