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Thorn · 01-31-2003

Q: How do you measure the gain? I would like to visually see the difference of my antenna vs. plain card.

A: Below is the quick and dirty way. Be advised this is very rough and very prone to error.
1) Get the best (strongest) dB level reading from a known AP using the card. This X dB. (eg -58dB)

2) Don't change the location or orientation. Plug in the antenna, get a new reading. This is Y dB. (eg -50dB)

Y + X = Antenna gain in dB. (Addition because these are negative values.)

-58dB + -50dB = 8dB.

In this example the gain would be 8dB.

Asked by hevnsnt and several others.
Answered by Thorn

01-31-2003	#15 (permalink)
Thorn Did you do the math? Join Date: Apr 2002 Location: Villa Straylight Posts: 10,084	Q: How do you measure the gain? I would like to visually see the difference of my antenna vs. plain card. A: Below is the quick and dirty way. Be advised this is very rough and very prone to error. 1) Get the best (strongest) dB level reading from a known AP using the card. This X dB. (eg -58dB) 2) Don't change the location or orientation. Plug in the antenna, get a new reading. This is Y dB. (eg -50dB) Y + X = Antenna gain in dB. (Addition because these are negative values.) -58dB + -50dB = 8dB. In this example the gain would be 8dB. Asked by hevnsnt and several others. Answered by Thorn __________________ Thorn "I'm The Doctor. I'm a Time Lord. I am from the planet Gallifrey in the constellation Kasterborous. I'm 903 years old and I am the man who is going to save your lives and all 6 billion people on the planet below... You got a problem with that?" Last edited by Thorn : 02-13-2003 at 07:05 AM.