[R-390] Varying gain [WAS: Filters]

[quartz55]

Great.  Well I still can't figure out how to 'search the archives', which 
and where archives, please, link please?  All I see is a list of months and 
years, no search feature that I can see.  All I get is email and the 
R-390 at mailman goes nowhere for me.  I guess I'm missing something or I'm too 
dense.

Never saw the items about the metalized foil vs. the film and foil.  The 
C551 was suggested here as the NTE.  I suppose since I have it, I'll use it, 
they weren't cheap.  I doubt if it will blow up.  So, it looks like the 716P 
orange drop capacitors seem to be film and foil.  I wonder why the metalized 
are suggested for HF filters and are not capable since I don't seem able to 
find the archives?

I really would appreciate some instruction on doing a search in the 
'archive' which seems to be the R390 FAQ place, but I'm not sure.  Even that 
doesn't seem searchable to me.  It's a good resource, but seems I have to 
read through it page by page as a pdf.