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) 
 
 
 
 
