TH78A.15
 
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CLOSING NOTES:
 
NOTE:  One version of  the mods I  collected  stated that removing "diode D8" 
       would open up  the 300 Mhz  band for listening  to the aircraft  band.
       I'm relating it because the information is out there being circulated.
       If you  look  at the  schematic,  D8 appears  to be  reverse  polarity
       protection for the  lithium backup battery.  I advise against removing 
       it since the  D5 removal  gives access to same  bands.  Also this mods
       says to hold the "F" key for  1 second then  press "TONE (low)" to get
       into the band (after the mod  is done).   This is how you  change your
       TX power level, how are you sopposed to do it after the mod?
 
 
I've  made these  mods (except for the  above note) on my  radio and  they DO 
work.   As for increased intermod  problems,  I have'nt noticed any yet. Best
as  I can tell the  full range of tuning is 50 Mhz to 999.999 Mhz.  There are 
gaps in the coverage,  for example  180 Mhz to 300.000 Mhz.  I used some test
equipment at work,  specifically an HP  8656B industial  signal standard with
the ultra high stability oscillator ($20,000 total  cost for that baby).  The
following is a list of receiver sensitivities at various  frquencies.  I used
12 dB SINAD with +/- 3 Khz deviation, and the volume set to 13  on the radio.

end of part 6