[R-390] Staggertuned IF Question

[Cecil Acuff]

Well I said I couldn't depend on my memory of this.....

My technical side said resistors but my memory for some reason had caps 
stuck in it.

Roy's comments about removing the resistors rings the bell for me...that was 
what I had heard...don't remove whatever component it was because it screws 
up the stage gain balance making the IF deck too hot by increasing the Q of 
each stage....

Memory is a great thing...just not always accurate as I have proven....

That still doesn't speak to the fact that some "A" radio's were stagger 
tuned and others were not.....at least that is what I have been told.

Cecil...
----- Original Message ----- 
From: "Roy Morgan" <roy.morgan at nist.gov>
To: "Cecil Acuff" <chacuff at cableone.net>; <n4buq at knology.net>; 
<R-390 at mailman.qth.net>
Sent: Thursday, September 14, 2006 1:30 PM
Subject: Re: [R-390] Staggertuned IF Question


> At 11:46 AM 9/14/2006, Cecil Acuff wrote:
>>... As I remember there is a capacitor involved on each can that sets the 
>>Q for the coil...I can't remember if the cap needs to be there when you 
>>are to stagger tune or vice versa....
>
>
> I seem to remember that the R-390A has resistors in each can that are the 
> "Q spoilers".  A capacitor is normally of such low loss that it will not 
> affect the Q by much.
>
> One (BAD) modification was to cut out the resistors in the -A IF cans to 
> get extra gain.. your receiver got real "HOT".  Trouble is, the IF 
> bandpass went to hell, and there was too much gain. NOT a good 
> modification.
>
>
> Roy
>
>
> - Roy Morgan, K1LKY since 1959 - Keep 'em Glowing
> 13033 Downey Mill Road, Lovettsville, VA 20180
> Phone 540-822-5911   Cell 301-928-7794
> Work: Voice: 301-975-3254,  Fax: 301-975-6097
> roy.morgan at nist.gov -- 
>
>