Leigh, wrote: I did the bandwidth mod while I built my KSB2, following the advice given here, and in the new KSB2 manual --
This morning I was able to work KH6BB ...Op Lee reported that I was "off frequency" and "too low." Any idea what to check for? The spectrogram plot looked a lot like the one in the paper... ---------------------------------------------------- Leigh, were you receiving on FL1? Filter 1 is always the filter used for transmission, so if you do not have SPLIT, RIT or XIT enabled, you are transmitting on exactly the same frequency you are receiving on when listening on FL1. If you are using a filter other than FL1 you might have as much as a 10 or 20 Hz error if it's set up properly. That's as close as the K2 is capable of resetting the frequency later. That is NOT enough to trigger a "too low" comment, however. It is enough to hear easily when listening to music, but not the human voice. One possibility is that you are simply passing a wider band of frequencies now with the wider filter setting that is making your sound 'different'. I widened the bandwidth of my SSB filter and now keep the low-end cutoff 3-db point at about 400 Hz to avoid the rumble of the "drone" in my voice from hogging the SSB power. I have FL2 set up lower with the cutoff at about 200 Hz because some stations sound better with a little "bass boost". One last point I'll make -- understanding that it is controversial. A lot of people say the Spectrogram puts the filters "right on". I've done it many times and I will agree that it's close, but Spectrogram has never been "right on" in my estimation. It's close enough that most people don't need to do any more, but I've always found it possible to improve the quality by monitoring my signal and making the final adjustments, just as the KSB2 manual advises. I record my signal in an auxiliary receiver and play back the recording to hear how I really sound; bone conduction of sound in your head really changes what you hear if you are listening to yourself in the auxiliary receiver in "real time". If you don't have an auxiliary receiver, get on the air with a buddy who is receiving you well, and try different settings of FL1 until he pronounces you "best". Ron AC7AC _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
