Clay, This is all about the calibration tables in the database. If your radio was calibrated with the FLEX-VU5K at the factory, then its data should be accurate. Going back to v2.0.8 may be incompatible due to the changes made in 2.0.16. I have copied Eric who is more familiar with these issues.
Gerald Gerald Youngblood, K5SDR President and CEO FlexRadio Systems(TM) 13091 Pond Springs Road, #250 Austin, TX 78729 Phone: 512-535-4713 Ext. 202 Email: [email protected] Web: www.flexradio.com <http://www.flex-radio.com/> Tune In Excitement (TM) PowerSDR(TM) is a trademark of FlexRadio Systems On Fri, Nov 12, 2010 at 6:27 PM, Clay W7CE <[email protected]> wrote: > Thanks for the info Gerald. I ran the same test using my 5000A with an > external 26 dB preamp on 6M. Same settings as below. PowerSDR 2.0.8 showed > a 2.9 dB improvement in noise floor compared with v2.0.16 (same as the > 3000). However, the 2.0.8 numbers weren't believable since they indicated a > noise figure of 0.7 dB. However, the 3.6 dB NF indicated by v2.0.16 is in > the right ballpark when you do the math for a 26 dB, 0.5 dB NF preamp in > front of the 5000A on 6M. I'll do more testing when I get a chance to put > the 5000A on the bench, but for now it looks like the v2.0.16 numbers are > more realistic. > > What's strange is that I've done this noise floor measurement before with > v2.0.8 and earlier and always showed a noise figure around 3.5 - 4.0 dB > (with the ext. preamp and a 50 ohm antenna termination). Now that the 5000A > has upgraded firmware (done at the factory for the V/U upgrade), when I run > with v2.0.8 I get different results from before. Any idea what might be > causing this? > > 73, > Clay W7CE > > > On 11/12/2010 3:15 PM, Gerald Youngblood wrote: > >> 2.0.16 sounds more like the correct noise figure for the FLEX-3000. >> Gerald >> >> >> Gerald Youngblood, K5SDR >> President and CEO >> FlexRadio Systems(TM) >> 13091 Pond Springs Road, #250 >> Austin, TX 78729 >> Phone: 512-535-4713 Ext. 202 >> Email: [email protected] <mailto:[email protected]> >> Web: www.flexradio.com <http://www.flex-radio.com/> >> >> Tune In Excitement (TM) >> >> PowerSDR(TM) is a trademark of FlexRadio Systems >> >> >> On Fri, Nov 12, 2010 at 4:59 PM, Clay W7CE <[email protected] <mailto: >> [email protected]>> wrote: >> >> I tried the comparison again, this time in a more controlled >> manner. I connected a 50 ohm termination to the antenna input of >> the 3000. In CW mode with a BW of 500Hz (50.192600 MHz), PowerSDR >> 2.0.8 shows the noise floor to be -142.5 dBM, which corresponds to >> a noise figure of 4.5 dB. PowerSDR 2.0.16 shows the noise floor >> to be -139.6 dBm, which corresponds to a noise figure of 7.4 dBm, >> which is 2.9 dB worse. Both measurements were taken with RX1 >> meter set to "Sig Avg", and in the Setup Dialog, "Show Decimal" >> was checked, the meter Average Time was set to 10000 ms, and >> Digital Refresh was set to 1000 ms. Shorter averaging times give >> similar values, but the digital meter display fluctuates around >> the center value. The preamp was set to Pre2 for both versions. >> >> I hope the additional data helps. >> >> 73, >> Clay W7CE >> >> >> On 11/12/2010 2:03 PM, Clay W7CE wrote: >> >> Gerald, >> I tried what you suggested and reset the database for both >> 2.0.8 and 2.0.16. PowerSDR 2.0.16 still shows the noise >> floor, as measured by RX1 Meter in "Sig Avg" mode, to be 3 dB >> higher than 2.0.8. Using SpecJT, both versions show the same >> average noise power when AF and AGC-T are set to 50 and 60, >> respectively. It appears that something has changed in the >> way the S-Meter reading is calculated. Rough calculations >> based on RX noise figure and current sky temperature, lead me >> to believe that the 2.0.8 reading is more accurate. >> >> I'm getting ready to hook up my 5000A, which I just got back >> with the V/U upgrade, and will see if it behaves similarly. >> I'll also try the 1500 later. >> >> 73, >> Clay W7CE >> >> On 11/12/2010 6:11 AM, Gerald Youngblood wrote: >> >> Clay, >> >> Try starting with a clean database on both versions. This >> is probably calibration data in the database and not an >> actual change in the noise floor. >> >> Gerald >> >> >> Gerald Youngblood, K5SDR >> President and CEO >> FlexRadio Systems(TM) >> 13091 Pond Springs Road, #250 >> Austin, TX 78729 >> Phone: 512-535-4713 Ext. 202 >> Email: [email protected] <mailto:[email protected]> >> <mailto:[email protected] <mailto:[email protected]>> >> Web: www.flexradio.com <http://www.flexradio.com> >> >> <http://www.flex-radio.com/> >> >> Tune In Excitement (TM) >> >> PowerSDR(TM) is a trademark of FlexRadio Systems >> >> >> On Fri, Nov 12, 2010 at 1:39 AM, Clay W7CE >> <[email protected] <mailto:[email protected]> >> <mailto:[email protected] <mailto:[email protected]>>> wrote: >> >> I just installed 2.0.16 on a Win7 Ultimate 64-bit machine >> (upgrading from 2.0.8). Initially, I'm running it with >> a Flex >> 3000, and it upgraded the firmware in the 3000 to >> 2.0.4.1. The >> FlexRadio Firewire driver stayed the same at >> 3.5.2.8028. After >> initial manual setup, I checked the local noise floor >> on 6M with >> the antenna pointed in what is typically my quietest >> direction and >> with the antenna elevated 40 degrees (to minimize the >> effects of >> any man-made QRN). The noise floor seemed high, so I >> shutdown >> 2.0.16 and started 2.0.8. It seems to work with the >> firmware >> upgrade, so I went to the same frequency and the >> indicated noise >> floor is 3 dB lower (better). Several iterations of >> switching >> versions yielded the same results. As far as I can >> tell, the two >> versions are configured identically. Both versions of the >> software are set to USB, 2.7k BW with the NB and SR >> off. Also the >> RX1 Meter is set to "Sig Avg" in both cases, and they >> both have >> AGC-T set to 69 and Pre2 selected. I've also noticed >> that the >> noise displayed in the panadapter seems to have a >> larger range of >> min and max peaks on 2.0.16 compared with 2.0.8. >> >> Why do the two versions show a different noise floor >> when used >> with the same receiver and antenna? Also, if there is >> a reason >> for the difference, which is more accurate? >> >> Tomorrow I should get a chance to try 2.0.16 with a >> Flex 5000A and >> a 1500. It will be interesting to see if there are >> differences in >> the indicated noise floor on those two receivers when I >> switch >> PowerSDR versions. >> >> 73, >> Clay W7CE >> >> _______________________________________________ >> Flexedge mailing list >> [email protected] <mailto:[email protected]> >> <mailto:[email protected] >> <mailto:[email protected]>> >> >> http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz >> This is the FlexRadio Systems e-mail Reflector called >> FlexEdge. >> It is used for posting topics related to SDR software >> development >> and experimentalist who are using beta versions of the >> software. >> >> >> >> _______________________________________________ >> Flexedge mailing list >> [email protected] <mailto:[email protected]> >> >> http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz >> This is the FlexRadio Systems e-mail Reflector called >> FlexEdge. It is used for posting topics related to SDR >> software development and experimentalist who are using beta >> versions of the software. >> >> >> >> _______________________________________________ >> Flexedge mailing list >> [email protected] <mailto:[email protected]> >> http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz >> This is the FlexRadio Systems e-mail Reflector called FlexEdge. >> It is used for posting topics related to SDR software development >> and experimentalist who are using beta versions of the software. >> >> >> > _______________________________________________ > Flexedge mailing list > [email protected] > http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz > This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used > for posting topics related to SDR software development and experimentalist > who are using beta versions of the software. > _______________________________________________ Flexedge mailing list [email protected] http://mail.flex-radio.biz/mailman/listinfo/flexedge_flex-radio.biz This is the FlexRadio Systems e-mail Reflector called FlexEdge. It is used for posting topics related to SDR software development and experimentalist who are using beta versions of the software.
