We've been making some final changes to firmware associated with the S-meters. Seemed like a good time to summarize how they work.
The S-meters in the K4 have been upgraded from the K3/K3S: - separate, color-coded S-meters for VFO A and B - higher resolution (twice as many bars) - calibration maintained over a wide range of input signals The two S-meters are calibrated at S9 = -73 dBm (50 uV). As you change receiver front-end gain settings (preamp off/1/2, attenautor 0 to 21 dB) the S-meter level remains virtually constant. Calibration also takes into account the main/sub receiver -3 dB splitters (if engaged) and any slight variations in per-band BPF loss. The upshot is that you get a very accurate signal level indication. In addition to the S-meters, the K4 provides a convenient way to see signal levels directly in dB (relative). Typically you'd zero the reference level on band noise, then tune into a signal to get the dB increase (S+N / N). This is useful for comparison tests. The numeric values for dB, both main and sub, are shown in the status area of the display, so they don't overwrite VFO B as on the K3/K3S. In conjunction with these changes, we're updating the "SMH" remote-control command (high-resolution S-meter read) so that it reads directly in dBm. The S-meters can also be tapped to show the "mini-pan," the K4's high-resolution tuning aid. Wayne N6KR ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
