Topband: Radial directivity

[Dan Zimmerman N3OX]

I added a bunch of new radials to the sides and front of the house,
and found that the signal from my TTL clock crystal transmitter out in
the field away goes DOWN by about 1dB with the new radials attached.
The transmitter is 800 feet away due south.  The radials almost all
run north-northeast.

Antenna is a 40 foot base loaded monopole.  The radial field without
added radials is 27 radials in a yard about 40 feet square.  The added
system extends about 80 feet northward around the house.  I laid down
about 600 more feet of wire.  What I added were fan-tipped radials
because I didn't think I needed a whole lot more in the backyard, so I
ran a couple to the edges of the backyard (two back house corners) and
then fanned out into the side and front yards from there.

What gives?  I still have to A/B the configuration with the little TX
out in other directions, but I'd expect better performance.

I've heard the claim that radial placement doesn't affect far field
directivity, but is that 100% true or just true to within a couple of
dB?  Maybe it's true for skywave but not groundwave?

I'll get back to everyone when I've tried the A/B test to the north
and let you know if I've picked up any directivity.

73,
Dan