[R-390] Image problem solved - Not.

[Renée Deeter]

I have an original 390A all  Collins sn 122 as well as an all original 
EAC sn 6k? (i forgot to note sn at the rear- no front tag). The Collins 
has an extremely hot  front end, two things I do note the oscillation 
suppression grid resistor is missing, and the AGC voltage divider were 
non existent both since fixed/upgraded. The problem has nothing to do 
with IF decks. The Early IF decks are not stagger tuned ( I have two ) 
and the later ones are. Having swapped IF decks -Stewart Warner ( my 
development deck) both Collins Decks  and the EAC.  The IF decks made 
very little difference on how hot the RF section runs. AGC has been 
extensively modified. both are similar in images present however far 
worse in the Collins. Both run Great! the Collins I run with the RF gain 
just a touch off max.
I have not taken the time to figure why...it is on my list of things to 
do.......
K6FSB, Renée

Barry wrote:
>> So.... This Collins 390a (with Collins RF deck) is hopping with images from
>> AM broadcasters, I just never bothered to notice them before.  But
>> apparently not the Stewart Warner.  When I get the chance, I am going to
>> connect the SW to the outdoor antenna for another comparison.  It is unknown
>> what the differences between the two RF decks could be, however I have
>> noticed that the Collins does tend to be a much "hotter" receiver than the
>> SW, good AGC action... but tending to pop up the noise floor when no signals
>> are present.  Maybe too hot.
>>
>> Jim M.
>>     
>
> Jim,
>
> This may not have anything to do with it, but do you know if both IF decks are stagger-tuned?
>
> Barry - N4BUQ
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