I was interested in WA8SRA's comments re background noise on 6 meters: > I just ran a test with an HP 8640B signal generator, on my FLEX-5000A: > > With a dummy load connected: > -- The noise floor (visually) averages -135 dBm, and it peaks out (using > the peak-hold feature of the panadapter) at -131.7dBm > > With the HP 8640B connected to ANT 3, and tuned to 50.125 MHz: > -- 1 uV produces an s-meter reading of -112.9 dBm (18 dB above the noise > floor peak) > -- 0.3 uV produces an s-meter reading of -122.4 dBm (9.3 dB above the > noise floor peak) > -- 0.1 uV signal not visible > > Another observation/metric: when I attach a 3-ele M2 3M6 yagi to ANT 3, > there is a barely perceptible (audible and visual) increase in the noise > floor. > > 73, Dale > WA8SRA
Dale's noise floor number with a dummy load attached to Antenna Port 3 of -135 dBm, blew me away. So, I put a 50 Ohm dummy load on my Flex 5000A and measured -121 to -122 dBm. That is without the ARR preamp which I recently installed. With it the circuit, the dummy load number is -119 to -120 dBm. With my 11 element M2 connected, the non-preamp number is abt -119. With the ARR in the circuit, the noise runs abt -110. It makes me wonder if my 5K is up to snuff. I would appreciate it if others would make similar measurements on 6 meters and post me the results. 73, Bill Tynan, W3XO _______________________________________________ FlexRadio Systems Mailing List [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexradio_flex-radio.biz Archives: http://www.mail-archive.com/flexradio%40flex-radio.biz/ Knowledge Base: http://kb.flex-radio.com/ Homepage: http://www.flex-radio.com/
