[Antennas] Think I've got this figured out, Re: AM Broadcast RX Antenna?

[KD7JYK DM09]

Looking at a couple of schematics, taking everyone's input and recalling 
what I've seen in radios over the years, it seems some added capicitance in 
series with a 102" CB whip will help with reception of an AM broadcast 
station about 1,000 miles out.

When I tested reception the other night, I held the 102" whip against the 
factory antenna which is covered in a thick black paint with no exposed 
metal.  There was an increase in volume and noticeable increase in signal to 
noise ratio.  I'm thinking the capacitance between the antennas, separated 
by the coating, and maybe a bit from my hands made the difference.

Not knowing exactly how much is needed, I'm going to make up a way to put a 
variable capacitor in-line and adjust for best reception, remove it and 
measure it.

I might find a fixed value cap, if not, a variable mica compression type 
should do, this is what most of my radios have, so it must be the way to go.

I spent the day researching parts to make the mount and secondary bracket, 
with a bit of luck I can get to building and installing this on my wife's 
truck within a couple of months.  I'd jump right on this but I'm in the 
process of clearing out the shop to rebuild my RFI locating vehicle which 
has been out of service for a year now due to a rabbit eating the engine 
harness!

Thanks for all the input!!!

Kurt