Hi all, I know this is a nit.
But the IARU state that the S9 signal level is -93 dBm for frequencies above 144 MHz. I for one did not know that the -73 dBm was only valid for lower bands until taking a look at the IARU recommendations. To me the IARU states that the -93 dBm is valid above the whole 2m band and therefore does not include the 2m band. The IARU recommendation R.1 is found at web page http://www.algonet.se/~k-jarl/ssa/IARU/smeter.html. Another reference is at http://webpages.charter.net/dig2bn/RF%20Comm-Elec%20Course%20Student%20Study%20Guides/S-Meter%20Calibration%20&%20IARU%20Standards.pdf <http://webpages.charter.net/dig2bn/RF%20Comm-Elec%20Course%20Student%20Study%20Guides/S-Meter%20Calibration%20&%20IARU%20Standards.pdf> Don, N0YE On 11/10/2010 1:58 AM, Alexandr Kobranov wrote: > Keep in mind that on VHF and up S9 on S-meter is by definition as > -93dBm on input (5uV) - it is 20dB difference from HF bands. > I suppose it is respected for K3/P3 K144XV setup. > Are there some exact valus (MDS, NF, S9 level) for old and new > firmware versions? Maybe I missed them, let me know out of list in > such case... > > 73! > > Lexa, OK1DST > K3/100 #727 > > > > > Dne 10.11.2010 4:55, N6JW napsal(a): >> I can certainly confirm this receive gain overcorrection problem on 2m. >> >> The "cpu sleep on rx" upgrade really helped cut back on the birdies. >> Thanks! >> >> But the overcorrection of the 2m gain compensation stands out like a sore >> thumb, particularly when one can actually see the relative amplitude of the >> signal on the P3. Of course, this is "just a small matter of programming!" >> and I'm sure we will get it right in due course. >> >> Thanks& 73 >> >> John, N6JW >> >> >> >> Jeff Cochrane - VK4BOF wrote: >>> Hi Terry, >>> Thanks very much for posting of those figures. >>> Although I do not have test gear that can back those numbers up I can say >>> that from my extensive on air testing that indeed, the 2M gain reduction >>> was overdone and to somewhere in the region your figures are showing. >>> The local (60+Km away) 2M FM repeater was normally S9+30db on earlier >>> firmware releases (around release 3.97 or so) on my K3 and once I got to >>> firmware revision 4.05 it had dropped to S9+5db, now that I am at revision >>> 4.14 it is now S5! >>> Nothing has changed at the repeater and all other radios tried with the >>> same antenna at my location show at least S9+20db signal strength. (And >>> usually full scale, it is an exceptional repeater, over 1500ft high and >>> with 50watts output to a 6+db gain antenna, it is almost full scale on my >>> handheld in the back yard here!) >>> Even allowing that the other radios have optomistic S meters I cannot >>> believe that they are all out by so much and by such a consistant amount. >>> >>> The overdoing of the 2m gain reduction has been the subject of a few >>> emails I have sent to Elecraft and to this reflector and to date I have >>> not heard an answer on the subject. >>> >>> Jeff Cochrane - VK4BOF >>> Innisfail, QLD, Australia >>> Elecraft K3# 4257 >>> >>> ----- Original Message ----- >>> From: w...@comcast.net >>> To: elecraft@mailman.qth.net >>> Sent: Wednesday, November 10, 2010 11:18 AM >>> Subject: [Elecraft] K144XV receive gain >>> >>> >>> After seeing several postings about the K144xv gain and experiencing >>> issues myself, I did some testing. >>> >>> Comparing a K3/K144XV on 2m vs 6m. >>> >>> On version 3.97 firmware, on 6m -87dbm yielded a S9 signal with the PR6 >>> preamp in but the internal preamp off - best setting. On 2m, this yielded >>> a S9+5 signal with the internal preamp still off. >>> >>> After loading 4.12 or higher, the same -87dbm gave the same S9 on 6m but >>> now only S5 on 2m and still only S7 with the internal preamp on. To >>> achieve the same S9 reading, I had to increase the signal level to -72dbm >>> with the internal preamp off. The release notes for 4.12 reference a gain >>> change on the K144xv and by the results of the 3.97 test I agree, there >>> was too much gain but instead of dropping 6 db or so, it appears that they >>> dropped 15db. Hopefully this will be rectified in the near future. >>> >>> Terry Price - W8ZN ex K8ISK >>> >>> > ______________________________________________________________ > 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 > ______________________________________________________________ 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
