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RF & Wireless — question 6 of 10

Write a real answer. It is graded against the question's rubric, and the mastery movement is computed by the same engine the product uses. Scoring here is deterministic rather than model-written, so this page costs nothing to run and nothing is saved. In a track built from your own posting, the same rubric is graded by the model, which is what produces feedback about your reasoning rather than about coverage.

You're deploying a LoRa sensor node: transmit power is +14 dBm, both the transmit and receive antennas have 2 dBi gain, the calculated free-space path loss at the deployment range is 145 dB, and the receiver sensitivity is -130 dBm. Your design requirement is at least 10 dB of fade margin. Compute whether this link closes, and by how much margin you're over or under the requirement.

This one resolves to a number. Give the value in the field below and your reasoning in the box — the number is checked exactly, by arithmetic.

dB

Units and SI prefixes are understood, including schematic notation: 4k7, 2.2 uF, 1.5e-3 A.

How sure are you?

Being confidently wrong costs more mastery than admitting a guess — that is deliberate, and it is how misconceptions get found.

Neither is graded, and nothing here is recorded.