2012/7/14 Michael Karcher <osmosdr(a)mkarcher.dialup.fu-berlin.de>de>:
I furthermore found out that this is not the only
filtering going on in
the RTL2832 chip in SDR mode. There seems to be a second anti-aliasing
filter before the DAC, making signals disappear that are at frequencies
above 0.7 times the sample rate (in the baseband), even if the
programmable FIR filter lets them pass.
That's probably an effect of the E4000
output filter. You can see the
filter bandwidth being set in the tuner initalization code.
--
Francesco Gugliuzza
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