How to calibrate an adjustable polarisation antenna Filters Particularly for EME, very narrow CW filters may be useful. If you prefer to use more modern technology look at Sliding FFT and DSP Filtering . This section describes part of the system I am currently using for EME and tries to explain why this method is equivalent to the use of several conventional DSP filters at different frequencies - where the computer continuously selects the best one. There are different opinions on what is the best way to receive weak CW signals, some use an ordinary SSB type filter, and others use narrow filters of different kinds. Look here for a description of my old TMS320C25 EME system and some audio file examples of typical EME signals as they reach my head phones.
Computers allow all sorts of interesting experiments.
It is well known that an EME signal is about 300Hz wide at 10GHz because of the different doppler shifts from different reflection points on the moon. On 144MHz the EME signal is much narrower than one would expect from the frequency ratio. Look here bandwidth measurements of a continous wave reflected off the moon for an experiment that clearly demonstrates that two different reflection types are present. My first generation PC receiver for MS-DOS is also becoming obsolete. There is no support for modern screens and the mouse has to be a serial mouse.