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Please correct me if I'm wrong:

In Page 56:

Question: PCMCIA card has 30 mW output. What is it in dBm?

Answer:
30 mW = 1 mW * 10 * 3
= 0 dBm+ 10 dBm + 3 dBM
= 13 dBM


I think it is completely wrong. It should be:
30 mW= 1 mW * 10 * 3
= 0 dBm + 10 dBm + 1,5 dBm (appr.)
= 11,5 dBm

or opposite,
13 dBm = 0 dBm + 10 dBm + 3 dBm
= 1 mW * 10 * 2
= 20 mW

Also same goes on in P:57

Question: Power source 30mW, cable loss 2 dB, amplifier 9 dB, result?

Answer:
30 mW = 13 dB
-2+9 dB= 7 dB
13 dB+7dB = 20 dBm
20 dBm = 100mW


However, I think answer should be:
30 mw = 11,5 dBm
-2+9 dB= 7 dB
11,5 dB+7dB = 18,5 dBm
18,5 dBm = 70mW (appr.)

if the given output was 20 mW it should be:
20 mw = 13 dBm
-2+9 dB= 7 dB
13 dB+7dB = 20 dBm
20 dBm = 100mW (appr.)

What do you think?

Hi I think this is correct :

13 dBm = 0 dBm + 10 dBm + 3 dBm
= 1 mW * 10 * 2
= 20 mW

If 20dbm = 100mw and 10 * 10 = 10 + 10 then the above should be correct.

I vote for the mw amount to be wrong, should've been 20mw instead of 30mw.

Hi I think this is correct :

13 dBm = 0 dBm + 10 dBm + 3 dBm
= 1 mW * 10 * 2
= 20 mW

If 20dbm = 100mw and 10 * 10 = 10 + 10 then the above should be correct.

I vote for the mw amount to be wrong, should've been 20mw instead of 30mw.

Hi,

There is no need for the all the fuss, this has already being corrected in errata

http://www.cwnp.com/cwna/CWNAStudyGuideErrataV3.pdf

This is most likely why no CWNP guru replied your post.

regars

Okechukwu

Hi, thanks for the replies.

I didn't know there was an errata for the book. It is strange to see such a mistake in a 3rd edt of a book.