SPICE modeling showed that the higher current was necessary to maintain the same maximum signal handling, but I don't remember doing IMD before/after measurements to verify that. Obviously, Elecraft feel that the device can handle the extra signal without increasing current.
Larry N8LP Don Wilhelm-4 wrote: > > Joe, > > Are you making an assumption that the P3 input impedance is 50 ohms? > That may or may not be true. I don't know the design parameters of the > P3, but it certainly occurs to me that it is not necessary to use a 50 > ohm input impedance. > > Yes, SDR-IQ and LP-PAN have the 50 ohm input, so connecting those > devices to the K3 IF Out would cause loss. > > 73, > Don W3FPR > > Joe Subich, W4TV wrote: >> >>> A 50-ohm match is not required in any case. >>> >> >> That’s not exactly true. With devices like LP-Pan or >> SDR-IQ that have 50 Ohm inputs connected to what is a >> high impedance output, the transfer loss (antenna to >> IF) was still in the range of -6dB even with the N8LP >> modification. The rest of the solution was to use a >> Clifton Labs Z-10000 buffer amplifier (high impedance >> input) in a unity gain configuration, install a 4:1 or >> 9:1 (step down) transformer, or modify the SDR-IQ for >> a 200 Ohm input. >> >> 73, >> >> ... Joe, W4TV >> >> > ______________________________________________________________ > 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 > > -- View this message in context: http://n2.nabble.com/Re-K3-Future-Factory-Hardware-Updates-New-beta-f-w-release-3-27-tp3512382p3514988.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ 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
