[ICOM] PRO III QST review

[Bill Tippett]

NE0P wrote:
 >But doesn't advertising that the PROIII has a 3IP of
+30db indicate that something was wrong with the
PROII, because its intercept wasn't that high.  In the
PRO II ads they seem to imply that the sensitivity in
the original PRO wasn't as good as it should have been

         Not at all...Icom was playing specsmanship
games using unrealistic 100 kHz spacings.  As the
ARRL Product Review noted on page 3:

"Under the same conditions at 5 kHz spacing---something
more akin to real-world amateur conditions (and this
time well within the passband of the receiver's 1 kHz
roofing filter)---we determined the PROIII's TOI to
be -17 dBm, 1.8 dB better than the -18.8 dBm we
calculated for its predecessor."

Note that the TOI of -17 dBm is no less than 47 dB (!)
BELOW Icom's advertising claim, and only 1.8 dB better
than the PRO II at that spacing (as ARRL notes above).

         Regarding sensitivity, if you look at the far left
column below (MDS) you'll see the III and II have
identical sensitivity for all 3 preamp cases (off/#1/#2):

http://www.elecraft.com/K2_perf.htm#5%20kHz%20numbers

         The moral of this story is that it pays to learn to
read these measurements ourselves, rather than blindly
accepting manufacturers's advertising claims.

                                         73,  Bill  W4ZV