Re: [Discuss-gnuradio] Noisy APT images

2014-03-06 Thread Nick Foster
The WFM receive block includes deemphasis processing for improving the sound of broadcast FM reception. This is going to screw up your APT reception. You'll be better off making your own WFM demod block -- it's just a quadrature demod followed by a low-pass filter. --n On Thu, Mar 6, 2014 at 7:4

[Discuss-gnuradio] Noisy APT images

2014-03-06 Thread Pablo Fernández Alonso
Hi, I'm trying to receive APT images from NOAA with a QHA antenna and I received noisy images. I use a usrp source block, then a low pass filter with 50 kHz of cutoff and 20 kHz of transition width, then a WBFM receiver and a resampler connected to the audio sink. I think that I should change the