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--- nyan:emc [2024/11/08 23:17] – removed - external edit (Unknown date) 127.0.0.1
+++ nyan:emc [2024/11/08 23:17] (current) – ↷ Page moved from emc to nyan:emc river
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+====== Noise Sources ======
+===== 868 MHz =====
+Nyan is using 869.525, currently with Meshtastic's "Long Fast", of 250kHz BW, SF11.
+Other users of this frequency include:
+  * Helium: 869.525 MHz, SF12, 125 kHz BW.
+  * The Things Network (LoRaWAN) ?
+I believe that LoRa on the same frequency but different spreading factor will appear as noise to the other radio.
+==== 3 Aug 2024 ====
+Went on roof to fit some speculative ferrites and extra power supply caps. Colin noticed a mobile phone sector aerial pointing right at us from a nearby church.
+Listening on a hackrf with heltec lora padel antenna, there was a very strong signal around 810MHz.
+There was no obvious increase in noise at 869 MHz when powered on the nyan box, suggesting the local power supply and electronics probably not at fault.
+The strong signal on 810 MHz went down 20dB when I put the church GSM aerial behind the building. I suspect therefore that inadequate filtering on the LoRa receiver is the problem. Maybe adding a filter would help.