[Discuss-gnuradio] PLL Problem

[David Scaperoth]

I have been testing the capabilities of the pll blocks to hopefully be 
used for a coherent receiver.

I have been using the gr.pll_ref_out(...) to lock a low IF signal.

What I have discovered is that the pll seems to be overdriving the 
processor (2.4GHz P4) when its used at high sampling rates (200kS/sec 
or above).  Is this something you have encountered??

The destination block also seems to affect the processing burden.  When 
using the audio card sink as a destination block (24kS/sec) the pll 
seems to work fine for a sinusoidal tone, but when I replace the audio 
card sink with null sink (same sampling rate) or the oscope gui, the 
processor goes crazy.   I may be setting this up wrong, but just the 
same I wanted to see if you have encountered this before.

I need this to work at high sampling rates like 2MS/sec so that I can 
detect larger bandwidth signals, but right now I'm no sure.

thanks

david scaperoth