> You only need the two -6 dB points, which can be measured to > a resolution of > 1 Hz and 0.1 dB using the internal AFV/dBV function.
This is true if the filter passband is flat, but I've found both ripple and slope in some INRAD filter passbands, so I always want to see the entire sweep to make sure I'm finding the true bandwidth. > You > should set AGC Off and ensure WIDTH (i.e. the DSP BW) is >> > than the filter you are measuring...otherwise you're > measuring the combination of XFIL plus DSP. I do this by > disabling all filters except the one under test and setting WIDTH > >> XFIL BW. Once you have the two -6 dB points, then you can > figure how > much offset to enter so these two points are equidistant > about the center. Yes. Thanks. These are important points to get valid measurements. Also make sure you are within the passband of the K3 audio circuitry. For example, it rolls off below 300 Hz. And, of course, that the RX equalizer needs to be flat. 73, Ed - W0YK _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
