Can someone please explain

[Sjinndoawi]

Ok, I really dont understand what Signal (dBm) means. I can see when I change my Antenna it will affect my level of my signal strenght. I can watch my (S-Meter) move back and forth between -55.6 dBm to -52 dBm with one Antenna and then put on a different Antenna and now the signal dBm will be moving between -40dBm to -35dBm. What does this mean? Does it mean the closer I get to (0) the stronger the signal is or better reception? I really dont understand how (dBm) plays out in relation to reception of a readable signal or for that matter antennas.

Can someone please help?

Brian

 

[digitalanalog]

The higher the signal strength, the better your receiving the signal.
If you move the antenna and the signal strength goes down, then that indicates your
receiving less of the signal, and vis -a-versa.

 

[j0nnyb1aze]

dBm is a measure of how strong a signal is in relation to a 1 millawatt reference signal. So 55dBm is 55dB stronger than th 1 millawatt reference, whereas -55dBm is 55dB weaker(signal loss).

on a side note:

dBi and dBd are often used for measuring antenna gain where dbi is gain over an isotropic radiator(theoretical spherical antenna), and dBd is gain over a dipole.

All of these "additions" make the measurements absolute instead of relative, since dB is measured against the input signal.

 

[fineshot1]

Does it mean the closer I get to (0) the stronger the signal is or better reception? I really dont understand how (dBm) plays out in relation to reception of a readable signal or for that matter antennas.

Can someone please help?

Brian

Yes - the closer you get to zero(from the -dBm levels) the stronger the signal strength.

Below is some online reference material for more reading. The last one has many
different conversion charts and calculators.

http://www.repeater-builder.com/measuring-sensitivity/dbm2uv.pdf

dBm uV conversion

Marc's Technical Pages: Converting uV & dBm

The dBm calculator - conversion dBm to volt mW voltage V dB dBu dBV dBm conversion and calculation milliwatt milliwatts - sengpielaudio Sengpiel Berlin

Audio calculations in English - acoustics calculator convert audio formulas microphone formula sound studio free audio calculator recording studio acoustic audio engineering online education sound calcs calculations - sengpielaudio

 

[Sjinndoawi]

Thanks guys that helps a lot . Now I understand