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[Question] jamming effectiveness #28

@ThisIsJeron

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@ThisIsJeron

Channel counts:

Looking at the actual arrays in config.h:

  • bluetooth_channels[] = 21 channels (classic Bluetooth)

Loop speed:

In RfClown.ino:358-406, the channel-hopping block has no delay(), so it runs as fast as the ESP32 can iterate. Each iteration does:

  1. random() — microseconds
  2. 3x RadioA/B/C.setChannel() — each is an SPI transaction, ~10-50μs

Rough estimate: ~100-300μs per loop iteration, so roughly 3,000-10,000 hops/second.

All 3 radios on the same channel

At line 361-363:

  RadioA.setChannel(channel);
  RadioB.setChannel(channel);
  RadioC.setChannel(channel);

All three radios are set to the same random channel each iteration.

  • Bluetooth Classic: BT hops at 1,600 hops/sec across 79 channels. Randomly hopping 3 radios (on the same channel!) across 21 of those channels is very sparse coverage.
  • WiFi: WiFi channels are wide (~22MHz) and the nRF24 carrier is narrow (~1MHz), so even hitting the right channel number provides limited disruption.

Would it not be better to assign each radio to a different channel instead of the same one?

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