Couldn't you just change the component values to raise the lower LPF to say, 16MHz, and run 30m & 20m through the lower filter, and 17m & 15m through the existing higher LPF?
73, Ross N4RP Don Wilhelm wrote: > Curt, > > Not practical. Yes, that might work, but you would need to design your > own board (or highly modify the KFL1-4 board). > The reason is in the Low Pass filters - there are only 2 - the board is > wired for 2 bands to use the lower frequency LPF and two more bands use > the higher LPF. The lower band LPF has a cutoff somewhere near 11 MHz. > The lower 2 bands use this LPF. So the lowest low band must be higher > than 1/2 the cutoff frequency - and in ham band language, that means 40 > and 30 are a good pair. The higher band(s) Low Pass filter cutoff is > just above the 15 meter band, so it is usable for any bands between > about 12 MHz and 22 MHz - that means any two of 20, 17 and 15 meters. > are the possibilities, but the board is wired so only 2 of these bands > can be used. > > You might want to consider a 4 band board plus an additional 2 band > board - say for 80 and 17, and configure the 4 band board for 40, 30 and > 20,15m. That would give you coverage from 80 thru 15 meters with a > filter board swap. > > 73, > Don W3FPR > > [email protected] wrote: > >> Since the KFL1-4 module allows either 17 or 15 selected at build time, I'm >> wondering whether building say ??,20,17&15 (leaving out 30M or 40M)is >> workable. It seems to me that this ought to work fine. With sunspot count >> increasing, am wishing for 4 band module more focused to the higher bands. >> >> I personally find the K1 a really enjoyable little QRP rig to use, and have >> a bunch of gear dwarfing it's diminuative size sitting idle on the desk. I >> actually like using XIT on the K1 better than using split on my QRO rigs >> for working DX. Recently have had VK2, EA1, E51, 5N0, CT9, KL7, and GA5 QSOs >> with 3 watts on 17 and 15. It would be nice to not need to change filters >> to QSO both of these bands. >> >> 73, Curt KB5JO >> >> >> > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > -- FCC Section 97.313(a) “At all times, an amateur station must use the minimum transmitter power necessary to carry out the desired communications.” ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
