Re: My Five Filters

Posted by Bill W4ZV on Feb 17, 2010; 3:23pm
URL: http://elecraft.85.s1.nabble.com/My-Five-Filters-tp4586377p4586571.html

Craig D. Smith wrote

But I would recommend the 200 Hz 5 pole rather than the 250 Hz 8 pole.

Ditto.  W4TV (?) measured the 250 (actually 370 Hz) versus the 200 and the latter had more rejection at ALL frequencies, even though it's only a 5-pole.  I only use my 200 ~1% of the time (500 Hz 8-pole the other 99%) but there are times when it's nice to have (such as large simplex pileups).

Someone previously commented on the 1000 Hz (actually ~1100 Hz) for CW.  I had one but found it too wide to be of much use.  If there are NOT a lot of strong signals around, the stock 2.7k will work about as well.  If there ARE a lot of strong signals around, the 1000 allows too many of them to desense the rig.  This is especially true if you use a low pitch as I do (3-400 Hz).  In that case the bandpass is shifted upwards from 200 Hz such that signals as much as 1000 Hz above zero beat will desense the K3 (e.g. a 200-1300 Hz bandpass for a 300 Hz pitch).

73,  Bill