# Maximum input sensitivity

Discussion in 'Homework Help' started by krogerson2, Jan 16, 2009.

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1. ### krogerson2 Thread Starter Member

Jan 8, 2009
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a reciever has a dynamic range of 81dB and a .55nW sensitivity what is the maximum allowable input signal.

Help i need a formula to figure this out!!

2. ### mik3 Senior Member

Feb 4, 2008
4,846
69
What is meant by dynamic range?

3. ### krogerson2 Thread Starter Member

Jan 8, 2009
24
0
that is exactly what the question in the book says the answer is 0.0692W but i need to know how to get to that point

4. ### mik3 Senior Member

Feb 4, 2008
4,846
69
I don't know but make a search in google for "receiver dynamic range" and you will find some answers.

5. ### KL7AJ AAC Fanatic!

Nov 4, 2008
2,182
415
Howdy:

Dynamic range is simply the ratio between the minimum detectable signal and saturation. (See the ARRL Handbook for more detail on this than you probably care to know!)

Since DB is a ratio...you simply need to find out what 81 dB above .55nW is.

Now you know.

eric

6. ### mik3 Senior Member

Feb 4, 2008
4,846
69
According to the explanation of KL7AJ:

dynamic range=saturation signal/minimum detectable signal

Convert 81dB in a normal number, say A, and then multiply A by 0.55nW to get the maximum input Watts allowed.