[Yaesu] QUERY TO THOS CLAIMING A FT1000D INTERMOD PROBLEM

James M. james119@iu.net
Wed, 13 Nov 1996 22:44:40 -0800


Robert Wanderer wrote:
> 
> What position is the FRONT END control?  You may have an overload
> condition if you're using NOR.  What happens when you switch to IPO
> or the 6 or 12 dB ATTEN posiitions?
> 
> I've a fairly older model and I don't see the problem as far as I can tell.
> 
> 73,
> Bob AA0CY
> 
> --
> FAQ on WWW:               http://www.contesting.com/yaesufaq.html
> Submissions:              yaesu@contesting.com
> Administrative requests:  yaesu-REQUEST@contesting.com
> Problems:                 ke7gh@contesting.com
> Sponsored by:             Akorn Access, Inc & KM9P

It makes no difference what position the front end is on, or the Rf gain
setting.  And the NB is off.  This is apparently intermod or similar
effect in the IF Unit, probably associated with one of the mixers or IF
Amps there.  And it's not a claim, it's for real.  You won't hear it
when there's only one signal audible in the filter passband, and you
probably won't hear it with multiple CW signals unless the freq. spacing
between them is just right.   For example, tune desired signal to center
of 500 hz CW passband.  Then inject a 2nd signal and slowly increase
it's freq. upward.  As you start to approach the upper edge of the
passband with this 2nd signal, you begin to hear an intermod product
whose "note" DECREASES as you increase the interferer's freq. (normally,
the note of this 2nd signal is INCREASING, but there's also this other
product which is simultaneously decreasing in beat note.)  It's probably
minor if all you do is work SSB.  

Jim N4BE

--
FAQ on WWW:               http://www.contesting.com/yaesufaq.html
Submissions:              yaesu@contesting.com
Administrative requests:  yaesu-REQUEST@contesting.com
Problems:  	          ke7gh@contesting.com
Sponsored by:		  Akorn Access, Inc & KM9P