Looking into refining my use of the LP-Pan on the 1st IF of the K3. One artifact is that the spectrum of the IF has a gain dip at the center frequency which apparently is due to interaction of the 2.8 KHz roofing filter that is also loading the IF.
I am wondering if I might be able to program the K3 to use an open xtal filter position when I am using the LP-Pan? I do not use any of the K3 beyond the IF so loss of use is not an issue; all signal processing is via the LP-Pan and a Delta44 soundcard to the sw running in my computer. I might have to add a resistor to provide proper impedance loading for proper gain levels to appear at the IF output. The dip in gain of the spectrum makes that frequency unusable in my application so looking for solutions (that are not invasive to the radio). One option is inserting a pin diode switch to isolate the roofing filter bank but that requires some RF designing and precise surgery on the RF board. 73, Ed - KL7UW ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
