On Thu, 12 May 2011 11:38:38 -0700 (PDT), Michael
wrote:

The W8JI web page goes to considerable length to bash the end fed Lazy
H with the twist, but since the real world performance of the center
fed Lazy H is less than stellar I'll have to give it a try.

Hi Michael,

As I offered, feed at the bottom, and observe proper phase
relationships. This page you reference also makes a note of those
relationships being improper will point your radiation straight up,
and straight down. Go figure - this is quickly revealed by EZNEC.

When I applied RF to the center fed
Lazy H four of my outside motion sensor flood lights would come on.

This is 100% rock-solid proof of Common Mode current on your
transmission line. This condition will cause extreme grief in trying
to match your transmitter to. It also skews the radiation/reception
lobes BIG-TIME.

Does this sound familiar?

The problem probably comes from your tuner's BalUn having a connection
to earth ground.

Solution to that (for all "balanced," horizontal antennas):
1. Use Coax.
2. Put a choke style (W2DU) BalUn at the antenna (ask about this).
3. Add a second choke a quarter wave away from the feed point.
OR
1. Fix the ground path inside your tuner (not as simple as it may
seem, unfortunately - in fact it can be an Herculean task - it may not
even be doable).
2. Obtain (purchase or build) the proper tuner.

Your antenna will then tune with vastly more grace, and you may even
find it performs much like common sense would expect. As I said
earlier, there is a world of experiential details that can kill an
EZNEC model's prediction - and it isn't the fault of EZNEC.

73's
Richard Clark, KB7QHC