Joe asked: What is the General Coverage Receive Filter, how does it work? If it is just another roofing filters, why not just use the 6.0 filter?
------------------------------------------------------- It's not, Joe. The KBPF3 provides additional receiver input bandpass filters. The input bandpass filters are L/C filters that are switched automatically according to the frequency band selected to protect the receiver from strong out-of-band signals hundreds of kilohertz or even a few megahertz away from the desired signal. The first I.F. "roofing" filters follow later in the signal path to provide selectivity within a few kHz or a few hundred Hz of the desired signal. The basic K3 is equipped with input filters covering the 160-6 meter Ham bands. These filters also allow reception near the Ham bands but, as you tune farther from a Ham band, the sensitivity will drop off as you move beyond the edge of the filter bandpass. This is most apparent when trying to listen to AM broadcast band stations below 1,000 kHz without the KBPF3, but a significant loss of sensitivity occurs whenever the basic K3 is tuned far from a Ham band. The KBPF3 provides additional input filters that are switched in automatically to cover the out-of-Ham-band frequencies between 500 kHz and 30 MHz. 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