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Re: Plagued with Mode J "noise" on TX



Jim Walls wrote:
> 
> Douglas Cole wrote:
> 
> > Scott Townley wrote:
> > >
> > <snip>
> 
> > What you really need to do is get a seperate antenna for each band and use the
> > DCI filters as they are a real "brick wall" when it comes to mode J desense (
> > well ok it is just my opinion) , or find yourself a nice bandpass cavity for the
> > vhf port etc.....
> 
> Keep in mind that a cavity filter will pass the 3rd harmonic just as well as the
> fundamental.  You need a low-pass filter of some sort.  That's why the multi-band
> diplexer has been suggested.
> 
> 73
> -----------------------
> Jim Walls - K6CCC

Yup , you are so right Jim , I had my brain only partially engaged when I did
that post ( someone had plowed into the rearend of my pickup and I wasn't all
here ) , but really what a person needs would be something like a low pass
filter , and it does seem that when I swept the DCI filter for two meters that
its pass response at 435 was negligable and actually quite good , but it did
have some harmonically related responses , just not in amateur portions of the
spectrum , guess I will have to go back and look at it again on the tracking
generator to make sure I'm not all wet ....

Thanks for the heads up though on the cavity , I should have caught that one
.....


we had this unidentified object in the sky yesterday .......

someone called it the "sun"   ;^)


-- 
Douglas Cole   N7BFS
AMSAT#26182 , K2 # 544
http://www.users.qwest.net/~cdoug3
Registered Linux user # 188922
"never go to bed angry , or on fire "
Gomez : the Addams Family.....
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