$129 spectrum analyzer Re: [Open-graphics] PCIe know-how?

[Dieter]

> >> So the question is whether you can make a good PC card digital 
> >> oscilloscope for $100.00.  You need an oscillator, frequency divider, 
> >> PLL, sample & hold, and DAC as well as the PCIe interface.  I seriously 
> >> doubt that this is possible for $100.00 but it does depend on the 
> >> maximum input frequency you wish to use, sample rate, and the accuracy 
> >> (and number of bits) needed.  Actually, you can spend over $100. on a 
> >> good DAC
> > 
> > You can get a 2.4 GHz spectrum analyzer for $129.
> > 
> > http://www.dunehaven.com/lcsa.html
> > 
> > If a 2.4 GHz spectrum analyzer can be sold for $129, why not a lower
> > frequency unit?
> 
> This device isn't really a digital spectrum analyzer.  It is a sweeping 
> RF signal strength meter.  Such a device is quite useful but it isn't 
> going to work for lower frequencies.

Okay, I'll bite.  What's the difference between a spectrum analyzer
and a sweeping meter?  Don't most (perhaps all) analog spectrum analyzers
work by sweeping a filter through the desired frequency range?

BTW, I'm not suggesting that the $129 unit can do the things that a
$$$$$ HP or Tek SA can do.