I am getting K3 sn 2308 sorted out. It has no mods, but all current firmware. I just installed a new version sub receiver board. The installation went fine.
The main Rx has a 2.7 kHz 5 pole in FL3, 400 Hz 8 pole in FL4, and 250Hz 8 pole in FL5. The sub Rx has new 2.7 kHz 5 pole in FL3, and a new 400 Hz 8 pole in FL4. Using a sig gen centered on the narrow passband, on 20m, I see the following dBV readings, with AGC off: using FL3 -> +6.0dB using FL4 -> +2.1dB using FL5 -> 0.0dB Those readings are with the FLx GN settings for FL3 set to 0, FL4 and FL5 set to max, 8 dB. On the sub Rx, using the same conditions, I get: using FL3 -> -2.0dB using FL4 -> -2.6dB with the FL3 gain set to 0 and FL4 set to 6dB. It looks to me like there is a problem with the older set of 8 pole filters being more lossy than the new one. The drop in cw signal strength is quite noticeable when engaged. Any advice as to whether this is something that is remediable? I could swap the old 400Hz with the new one, or move the older filters to different positions, but that is a bit of work. Al ______________________________________________________________ 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