[Flexradio] QRM filter techniques

2010-11-21 Thread John Bair, KJ7B
Let's say we are tuned and listening to a USB transmission, and there is another USB transmission 1-2 kc lower on the band, such that the two transmissions overlap. Other than sliding or shrinking the passband, turning off preamp or lowering AGC gain to try to reduce the QRM to noise level, what

Re: [Flexradio] QRM filter techniques

2010-11-21 Thread Graham Haddock
John: If they are coming from different directions, then you can use the second receiver as in Flex-5000 option (on a separate antenna) to create spacial diversity, or even rotate a directional notch onto the interferer. These directional notches are quite narrow in angle, but can be many tens

Re: [Flexradio] QRM filter techniques

2010-11-21 Thread Jerry Flanders
If the interfering signal is on a different azimuth, it is possible the diversity features already in beta PSDR would help if you have the 5000 with rx2 and a diversity antenna. w9oy has written up some of his experiences on his blog. Jerry W4UK At 05:17 PM 11/21/2010, John Bair, KJ7B wrote: