On Sat, 26 Sep 2020 20:13:15 -0400, Ralph Mowery
wrote:

In article ,
says...
h a spectrum analyzer and an RF sweep generator.

The rotor also has a bypass braid around it which many people
forget.

What is a bypass braid? I've never heard of the term. Neither
has Google search. Do you mean something like quad shielded
RG-6/u?

A large tree is going to hit by lightning first.

Large height or large girth?

Bypass braid for a rotator is for lightning protection.

Methinks it has more to do with discharging a static electricity
buildup (St Elmo's Fire) than protecting against a lightning hit or
lightning induced current.

You put a piece
of wire to the mast above the rotator and then to the mast below the
rotator. That is suppose to make a good connection from the top mast to
the bottom mast.

Well, I've never seen such a thing, never had anyone request it, and
couldn't find with Google any installation instructions recommending
such a practice.

It is not so much the actual gain of the amplifiers, but the noise
figure. If just feeding one or two tv sets all the gain needs to be is
just to make up for the loss of the feedline if the amp is very near the
antenna and a little more depending on the noise figure of the TV set.
If the amp is near the TV, it needs very little gain (maybe 10 db) and
better have a noise figure much lower than the TV tuner.

Agreed. I think I mumbled something about too much gain causing
intermod problems further up this thread. Another problem is loss of
dynamic range when the added gain also raises the noise floor but not
changing the overload point. Way back in the dark ages of TV, the
receivers were stone deaf and any kind of RF preamplifier offered a
performance improvement. These days, with GaAs low noise front ends,
the best that a preamp can offer is to compensate for coax cable
losses.

Hopefully a tall tree will get hit first,but no guarentee.

We don't get much lightning here on the left coast[1]. I live in a
forest full of 100ft and higher trees. I know of three local trees
(out of millions) that were hit by lightning in the past 40 odd years.
Both were in rather odd locations, such as the bottom of a canyon or
surrounded by taller trees. My best guess is the tree holding the
most water has the highest conductivity and therefore gets hit first.


[1] Mother nature delivered our accumulated savings (with interest)
of lightning on Aug 15, 2020, with a really impressive display of
flashing lights, and starting 500+ big fires that are currently trying
to incinerate California, Oregon, and Washington states. 5 million
acres burned and climbing.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558