With all due respect, that URL doesn't indicate anything of the sort. It shows that with the power increase both the first and second sidelobes exceed the limits in the IEEE spec - -30dBc and -50dBc respectively. This in turn _may_ cause FCC band-edge limits to be exceeded - this is not shown. In addition, no measurement is made of harmonics, some of which fall in FCC restricted bands. Harmonics _will_ increase with increased power due to PA non-linearity. Finally, no measurement is made of any other out-of-band terms which could be present and could exceed limits.
The reality is that most vendors will be trying to achieve as much tx power as possible while meeting a number of constraints: 1) Spectral Mask (IEEE) 2) FCC limits on harmonics, band-edges and other emissions 3) Power consumption 4) EVM Unless power consumption is the limiting factor - probably not in an AP - then increasing the tx power by any significant amount is likely to cause some limit to be exceeded. I would also point out that using the power output quoted in the IC data sheet is somewhat misleading. Actual in-system performance depends upon board-layout, component selection, and other factors. - de ----- Original Message ----- From: "Andrew Stern" <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Wednesday, January 14, 2004 7:05 PM Subject: Re: stupid tx power tricks (was Fw: [BAWUG] bridging help) > Not to spoil the fun, but the WAP11 "dirty" hack wasn't all that dirty > according to independent verification. > > http://explorer.cyberstreet.com/wap11/WAP11_Spectral_Output.html > > Andrew Stern > [EMAIL PROTECTED] > > Casey Halverson wrote: > > > I'm not a big fan of power anymore. High antenna gain is much more > > productive, and its safer that way too... > > > > I think there is a big problem with modifications, especially done by > > hackers that have no test equipment. And yes, even a few milliwatts > > adjustment brings it out of type acceptance. Those power amps have have > > specified min/max values, but that doesn't mean it will work a damn at > > any given value. > > Lets take the WAP11 hack for example. Not only did it splatter the > > entire 2.4GHz band, it put out spurs up and and down the spectrum. EIRP > > limits mean nothing when your power isnt even on frequency. All one > > needs is a nice little spike on the input of an emergency services > > repeater to make you really popular with the FCC .. Or worse yet, the > > hams *duck* > > > > Given linksys' colorful history of out of specification operation, I > > think it would be interesting to test out the WRT54's emissions after > > the hack. > > > >> -----Original Message----- > >> From: Brian Lloyd [mailto:[EMAIL PROTECTED] Sent: Wednesday, January > 14, 2004 12:00 PM > >> To: Greg DesBrisay; Wirless Forum > >> Subject: Re: stupid tx power tricks (was Fw: [BAWUG] bridging help) > >> > >> I understand and you are correct. But I tend to be less concerned > about rules than about safety and good engineering. And from a practical > point of view, if the signal quality is acceptable and the EIRP is > within limits, I doubt the FCC will come knocking on your door. > >> > >> (Disclaimer: you violate FCC rules at your own risk. Don't blame me.) > > > > > > > > -- > > general wireless list, a bawug thing <http://www.bawug.org/> > > [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless > > > > > -- > general wireless list, a bawug thing <http://www.bawug.org/> > [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless > -- general wireless list, a bawug thing <http://www.bawug.org/> [un]subscribe: http://lists.bawug.org/mailman/listinfo/wireless
