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ISRO (VSSC) Technical Assistant Electronics 2018 Official Paper

Option 1 : 1mW

Subject Test 1: Electrical Basics

3098

20 Questions
80 Marks
30 Mins

**Concept:**

To convert Pr in watt from dBW, we use the relation:

Pr (dBW) = 10 log10 (Pr(W)]

**Calculation:**

Given:

Power in dBw = -30 dBw

-30(dBW) = 10 log10 [Pr(W)]

log10 [Pr(W)] = -3

[Pr(W)] = 10^{-3}

[Pr(W)] = 1mW