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OMNI V AND VI SPECIAL CW FILTERS

Subject: OMNI V AND VI SPECIAL CW FILTERS
From: K8DO@aol.com (K8DO@aol.com)
Date: Wed Sep 6 14:09:25 1995
Hmmmm...Why would a contestor consider a 6 dB shape factor of 2.0 Kc  a
handicap?  :)     ok ok  couldn't resist.... 

This would be a darn good shape factor for a 1.8 Kc SSB filter...
I would verify the filter number in each filter slot on that radio....
How was the setting on your passband tune determined for this test?
Have you/we tested other VI's? 
 Mine is a bit narrow (by ear), but acceptable for general listening IF the
PBT is dead on...Maybe you need to spring for a new 2.7 filter..... (can I
have the old one, pretty, pretty please?)
Other comments, guys?
--------------------------------------------------------------------

On the CW filter at 400 cycles.... I don't know... I will have to muck with
the ST and PBT and try it a bit and see if I like that... If I do I would be
interested....Will let you know what I think...

Denny   k8do@aol.com

>From Gary Sutcliffe" <gary.sutcliffe@mixcom.com  Wed Sep  6 18:36:41 1995
From: Gary Sutcliffe" <gary.sutcliffe@mixcom.com (Gary Sutcliffe)
Subject: NCJ Column
Message-ID: <199509061736.MAA17782@mixcom.mixcom.com>


Hi Gang
 
Deadline time for the next NCJ is quickly approaching & once again I am asking
for your help for my Contest Tips, Tricks & Techniques column.  The upcoming
issue's topic is:
 
              Topic for Nov-Dec 1995 (Deadline September 12)
 
        How do you divide up your time between contesting and family?
        How do you help them understand your interest in them? What sort
        of support does your family give you before and during a contest?
        How do you reward them for their support (or tolerance!) after a
        contest?
 
 
Please email your responses directly to me.  Thanks again & 73 - Gary
 
-- 
 Gary Sutcliffe  - W9XT             Unified Microsystems (414) 644-9036
 ppvvpp@MIXCOM.COM                  PO Box 133, Slinger WI 53086


>From w7ni@teleport.com (Stan Griffiths)  Wed Sep  6 19:24:12 1995
From: w7ni@teleport.com (Stan Griffiths) (Stan Griffiths)
Subject: OMNI V AND VI SPECIAL CW FILTERS
Message-ID: <199509061824.LAA23140@desiree.teleport.com>

>Hmmmm...Why would a contestor consider a 6 dB shape factor of 2.0 Kc  a
>handicap?  :)     ok ok  couldn't resist.... 
>
Shape factor is a dimensionless term so you can't have a shape factor of
"2.0 Kc".  Shape factor is usually the ratio of the filter width at 6dB down
to the filter width at 60 dB down.  At least that was the definition used in
Tektronix Spectrum Analyzers.  HP used the 3dB to 60dB width ratio which
made comparing Tek to HP an apples vs oranges situation!  Shape factor
describes the steepness of the filter skirts and a shape factor of 1.2  is
pretty good for a 1.8KHz filter.

>Other comments, guys?

>Denny   k8do@aol.com
>

That's my $.02 worth.   Stan   W7NI@teleport.com  (note new internet address)


>From sellington" <sellington@mail.ssec.wisc.edu  Wed Sep  6 22:01:23 1995
From: sellington" <sellington@mail.ssec.wisc.edu (sellington)
Subject: K6STI Loop
Message-ID: <n1401719193.43932@mail.ssec.wisc.edu>

The horizontal loop described in Sept. QST looks like a very attractive
receiving antenna, especially to those of us with limited space.  A logical
arrangement is to hang the loop around the tower, with the tower right at
the center of the loop.  There's a problem, however, if the same tower is
shunt fed as a transmitting antenna.  After having lots of trouble with
coupling to another feedline near the tower, I expected some coupling to
the feedline for the loop.  I modeled a loop 20 feet/side, 30 feet 
above the ground with EZNEC, and found that it was virtually impossible 
to decouple the feedline.  Even with 8 common mode chokes, each 2,000
Ohms, on the feedline in various locations, it looked like well over 1 kV
would appear across the loop matching transformer when 
transmitting on 160 M.  80 M isn't as bad, but would still take 
quite a few chokes.  It's not hard to reduce the coupling enough to avoid
upsetting the transmitting antenna, but it could be difficult to keep 
the loop matching transformer from burning up.  At this point, the only
solution I can think of is to use lots of decoupling chokes on the feedline,
PLUS a matching transformer capable of withstanding a common mode
voltage (primary to secondary) of a couple KV.  Any other ideas?

Scott  K9MA
sellington@ssec.wisc.edu

>From Ken Silverman" <ken.silverman@CCMAIL.AirTouch.COM  Wed Sep  6 23:04:47 
>1995
From: Ken Silverman" <ken.silverman@CCMAIL.AirTouch.COM (Ken Silverman)
Subject: TS-950SDX Questions
Message-ID: <9508068104.AA810422033@CCMAIL.AIRTOUCH.COM>

     Hi Gang,
     
     In the near future I'll be going on a contest-expedition, where the 
     host station has a TS-950SDX.  I wonder if any of the TS-950SDX owners 
     out there could answer a few questions.
     
     These questions revolve around the use of the TS-950SDX for in-band 
     multing on the RUN station band in a M/S or M/M situation.  While 
     in-band multing may be best implemented when using 2 antennas 
     separated by a few hundred feet, we are searching for a different 
     technical, albeit compromised, solution in case we cannot get the 
     antenna separation. 
     
     1) Can the audio in the SUB-RX be completely separated from the Main 
     audio, and provide 2 separate audio paths out from the radio?  Such 
     that another op could be tuning around on the SUB-RX, and only he 
     could hear the SUB-RX audio, while not disturbing the RUN/Main RX?  
     While this may be less than desirable from an ergonomics point of 
     view, it still may provide limited functionality.
     
     2) Is a separate RX output available?  If no specific jack on the 
     back, then possibly from the ACC or REMOTE DIN jacks?  The goal would 
     be to run another receiver from the RX output of the 950.
     
     3) If we install a Y-splitter in the RX ANT OUT to RX ANT IN patch 
     cord, such that one path goes back into the radio, and the other path 
     goes to the second radio, will we see a severe degradation of the RX 
     level?  I assume that the split should cause a 3 dB reduction, but ya 
     never know.
     
     4) At what point in the RX chain is the RX ANT OUT to RX ANT IN patch 
     cord?  I assume that it is switched/muted out of the line during 
     transmit?
     
     Any other thoughts regarding the technical possibility of in-band 
     multing would be greatly appreciated.
     
     Please send your answers directly to me.  I will post a summary to the 
     reflector.
     
     Many thanks for your assistance,
     
     Ken, WM2C
     
     ken.silverman@airtouch.com 
     (short version of addr.)
     


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