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[TowerTalk] 1dB more RF Power?

To: <towertalk@contesting.com>
Subject: [TowerTalk] 1dB more RF Power?
From: "Jim Thomson" <jim.thom@telus.net>
Date: Wed, 6 May 2020 09:40:34 -0700
List-post: <mailto:towertalk@contesting.com>
<You will almost being not readable with your top end extended to 3.8-3.9 kHz
<or higher on a standard filter which we use over here, especially when you
<raise signals above 2.8kHz by EQ.
<Band width above 2.7kHz is illegal here.

<73
<Peter## Agreed.  It  appears you  folks  have  gotten  the  short  end  of  
the  stick....too  bad.##  We  increase  BW  by  using  filters  wider than  
normal  2.8  khz.   Which  is  done  with  either  wider  collins  mech  
filters  at  455 IF,or  wider  xtal  filters  for a higher  IF.   Or  any  BW  
you  want  with  xcvrs  like  ANAN,  flex  etc.  In  my  case,  I use a 6khz  
collins  mech  filter  at 455...and a 5.8 khz  xtal  filter  at  the  higher 
IF..on  both  my  yasesu FT-1000-MP-MKVs.  Upper  +  lower  BW  is limited  on 
TX  with  the  use  of  external digital EQ.  IE:  brickwall the  top  end  at 
say 3400 hz, or  3400 hz, 4500  hz  etc...and  ditto  with  bottom  end.The  
MK-V  will  generate a SSB  signal in  either the yaseu  digital  format....  
with a max  tx  bw  of  100/200/300 - 3100  hz.  Or in  the  analog  
conventional  method,  using  mech  + xtal  filters.  With  the wider analog  
filters,  I  can  still  narrow  down  the  RX,  using the  width +  shift  c
 ontrol.  I  also  employ  a  lot  of  external audio  processing  on  RX...  
like  adding  harmonics to  narrower ssb  signals,  +some  RX  eq....+  
downward  expanders  etc.   ##  Several  of  us  have  run  hundreds  of  tests 
 using  varying  top  end  BWs...  with  real  weak  ssb  signals.  In  every  
case,  the  widertx  BWs   prevail.  Flip  side is....  wider  TX  +  RX  BWs  
are more  prone  to  QRM. Jim   VE7RF    
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