CQ-Contest
[Top] [All Lists]

Re: [CQ-Contest] Re: ON4UN and the Ten-Tec Orion

To: "Marijan Miletic" <s56a@bit.si>
Subject: Re: [CQ-Contest] Re: ON4UN and the Ten-Tec Orion
From: Bill Turner <wrt@dslextreme.com>
Reply-to: wrt@dslextreme.com
Date: Sat, 18 Oct 2003 11:02:48 -0700
List-post: <mailto:cq-contest@contesting.com>
On Sat, 18 Oct 2003 10:24:45 -0000, "Marijan Miletic" <s56a@bit.si>
wrote:

>I am sure that reputable antenna experts know that the minimal RTTY RX
>bandwidth should be 170 + (2 x 45) Hz!
>
>The only Orion data provided by ON4UN were filter passbands.  We can see
>clearly that even 250 Hz filter actually measures 240 Hz.
>
>Deplorable Icom and good old Collins offer 330/350 Hz filters for RTTY mode.
>
>"Write" or wrong?
>
>73 de Mario, S56A, N1YU

_________________________________________________________

Right.  My ICOM IC-746PRO using a 250 Hz filter copies ok if the
sending station uses 170 Hz shift, but if he is using 200 Hz, the copy
gets a bit erratic.  Widening out the filter to 300 Hz makes good copy
again.

I would STRONGLY recommend everyone use 170 Hz shift only.  The
various AEA products default to 200 Hz for some reason.  PLEASE change
them to 170 Hz.  I have a spectrum scope I use when receiving RTTY and
I can easily tell which stations are at 200 Hz.  Fortunately the
number is decreasing with time.

I don't believe AEA is in business any more, but their legacy lingers
on.  :-(

-- 
Bill, W7TI

---------------------------------------------------------------
    The world's top contesters battle it out in Finland!
THE OFFICIAL FILM of WRTC 2002 now on professional DVD and VHS!
       http://home1.pacific.net.sg/~jamesb/
---------------------------------------------------------------

_______________________________________________
CQ-Contest mailing list
CQ-Contest@contesting.com
http://lists.contesting.com/mailman/listinfo/cq-contest

<Prev in Thread] Current Thread [Next in Thread>