[R-390] Trim Caps on Mechanical Filters

[Flowertime01 at wmconnect.com]

Tim,

OK so now you have looked under the two different types of IF decks and find 
ample space to place four trimmer caps.

Before the end of 2006 as a new year resolution please provide the R390 
reflector here a very concise write up equal to a field modification procedure. 
Exactly detail how to modify the non cap chassis to a cap chassis. Please provide 
a detail list of parts. Please provide mechanical drawings such that the 
mechanical mounting parts can be fabricated from the drawing to provide some of 
the parts to make up the complete parts kit. Please include in the field kit 
installation, a template for drilling the side of the receiver frame. You get the 
parts list and detailed instructions and I know we can find the parts to do 
kits.

I write that prior to 1975 the military looked at the problem a couple times 
and chose not to spend the money on it. Your response is there is room on the 
deck to do it. If that was the only item I am sure the military would have 
done it. Because I said there was not room on the chassis and you think there is 
room every thing else I posted is mostly not credible. You rate eight good 
years of my life as fiction. I try to write this really boring trivia with some 
humor. Some Fellows today wonder what the engineers in the past were thinking 
and why they made the choices that were made. I call these choices compromises. 
I find most are motivated by return on investment. How much bang do we get 
for the buck? There is value to be taken away from these questions and answers. 
>From these questions and answers I take way a lot of humor and get much 
practice with my typing and writeing skills. I am sorry it falls on you to grade my 
work. A boring job but some one has to do it. I do try to keep it on the R390 
subject while varied. While most days I do enjoy taking a cut at providing 
some insight and sharing what I saw go down in my life, I am sorry my post are 
not up to your exacting critical reading expectations. I believe if I had more 
writing skills, I could have been a good author and would not have had to make 
a living prior to my retirement at age 55, assembling auto engines, repairing 
radios, being an electrician, and a computer scientist. I will continue to 
share my response to questions here on the R390 reflector and try not to worry as 
much.

Here's your chance. I bet lots of fellows own R390/A decks without the 
variable caps and would like to have the write up to make the modification. It sure 
would be a very nice addition to the R390 resources. 

I am looking forward to your work and the chance to modify one of my decks 
from your wonderful work. While the military considered and rejected the idea 
having the IF decks field modified, that would not stop some R390/A owners from 
taking on the task and doing it very successfully. Many Fellows have many more 
resources today for doing the task than were available back it the old days.

How about the can on top, Will it need to change size or can we squeeze every 
thing in the original can?

How much improvement will we get in the signal to noise ratio?

How will the band pass be effected? 

What gain will one get for the pain?

Just because one can make the change should we make the change?

Roger