From philabs!philmtl!uunet!samsung!zaphod.mps.ohio-state.edu!sdd.hp.com!hplabs!hpcc01!col!kenw Sat May 19 00:08:04 EDT 1990 Article 21147 of rec.ham-radio: Path: philabs!philmtl!uunet!samsung!zaphod.mps.ohio-state.edu!sdd.hp.com!hplabs!hpcc01!col!kenw >From: kenw@col.hp.com (Ken Wyatt) Newsgroups: rec.ham-radio Subject: Re: IC-24AT Receive Mods Message-ID: <24300005@col.hp.com> Date: 17 May 90 16:07:15 GMT References: <24300004@col.hp.com> Organization: HP Colorado Springs Division Lines: 33 Following the frequency expansion modification (as specified by Icom), a sample IC-24 was recently tested for tuning range and input sensitivity for an S9 signal. While the sensitivity measurements should not be directly compared with the manufacturer's specifications (usually measured reference to a signal-to-noise quieting ratio), this "quick and dirty" data should give you a good idea of the sensitivity to a medium-strength signal. Tuning Range Mode Band Sensitivity for S9 Signal 74 - 107.995 MHz (fm) VHF range approx 1 mV 108 - 136 MHz (am) VHF range 10 - 30 uV 138 - 240 MHz (fm) VHF range 1 uV - 1 mV (1) 250 - 302 MHz (am) VHF range 50 uV - 1 mV (2) 310 - 354.995 MHz (fm) VHF range 50 uV - 3 uV (2) 355 - 409 MHz (fm) UHF range 3 - 10 uV 417 - 490 MHz (fm) UHF range 1 uV - 100 uV (3) 805 - 955 MHz (fm) UHF range 10 - 100 uV Notes: (1) The sensitivity from 138 - 150 MHz was 1 uV. From 150 - 240, the sensitivity decreased almost linearly from 1 uV to 1 mV (with input voltage plotted logarithmically). (2) The sensitivity increased almost linearly for both these ranges (with input voltage plotted logarithmically). (3) The sensitivity plot looked like a "U" with the bottom of the "U" corresponding to the range 440 - 450 MHz (1 uV). The sensitivity then got worse below 440 and above 450. (Tests courtesy of WB6GTM)