Agreed with your points. However the statement I originally addressed is;
"the 3rd pin ground is not good lightning protection" or something to that
fact. The 3rd pin system was never intended to be such.
I'll revert to my manual from Motorola, all 513 pages of it, on the topic of
ground system construction and integration. We must all agree that
lightning protection and mitigation and grounding must be constructed as a
system. It is not a thing and it is far from being as simple as a driven
ground rod or rods with a conductor connected to ones radio.
In conclusion the topic is much too broad to be adequately discussed in a
venue such as a product related reflector.
73
Bob, K4TAX
----- Original Message -----
From: "Cecil" <chacuff@cableone.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Friday, May 16, 2014 9:21 AM
Subject: Re: [TenTec] Eagle problem?
I can agree with "All lightning protection must BEGIN outside the
structure."
But the fact is we, by the very nature of building a radio station, have
invited lightning inside by virtue of multiple copper paths. Our various
feedlines, rotor control cables, remote antenna switch cables etc..
We have to build a last line of defense inside the shack to deal with, as
effectively as possible, whatever remaining strike potential makes it
through our outside defenses.
Tying those two protection systems together is not inviting the energy
in...it's extending the protection all the way to the equipment we are
working so hard to protect.
Of course there are two camps..I have a friend that believes don't ground
anything...including the tower....that encourages...invites a lightning
strike to occur.
Everybody knows lightning seeks the best path to ground...
I guess the best course is to do what makes one sleep best at night....
Cecil
K5DL
Sent from my iPad
On May 15, 2014, at 3:49 PM, Robert <rmcgraw@blomand.net> wrote:
All lightning protection must exist outside of the structure.
Do nothing to invite lightning inside unless you desire a lot of damage.
73
Bob K4TAX
Sent from my iPhone
On May 15, 2014, at 3:39 PM, Brian Carling <bcarling@cfl.rr.com> wrote:
AC 3rd pin is not going to be a very effective ground for protection
from lightning damage.
Best regards - Bry Carling AF4K
On May 15, 2014, at 4:17 PM, Robert <rmcgraw@blomand.net> wrote:
Braid is not the best choice for a low inductance RF path. It is
although necessary for flexible applications.
Personally I bond all equipment to the station supply and do not use
anything but the AC 3rd pin for safety reasons.
73
Bob, K4TAX
Sent from my iPhone
On May 15, 2014, at 2:20 PM, Carter <k8vt@ameritech.net> wrote:
On 5/14/2014 5:56 PM, Stuart Rohre wrote:
Some Yaecomwoods do suffer from RF entering the rig.
MOST ANY rig will if you have a bad shield connection on coax jumper,
or have rig too close to the antenna, (second floor shack), and there
are many other rig and feedline issues to rule out in any RFI case.
True, can be many causes, but I am in a basement shack. Also, a few
years ago, I used a Drake TR-7 on SSB with everything else the same
and it worked fine. However, I realize that the TR-7 was not as
"computerized" (dependent on microprocessors) as the Omni VI.
Rule of thumb: Power all equipment from same circuit breaker of the
house. That ensures AC grounds will not be coming from widely
different locations. IF you have to use a long ground wire for
lightning protection ground on the station (like from second floor
shack), consider that it could act as an "antenna" for pick up of RF
from the real antenna. You may need tuned radials, or a radial for
each favorite band.
Good tip and I believe I am on the same breaker for all the ham
equipment. Again, a basement shack and 5 or 6 feet of a single 3/4
inch wide braid from the ground of each piece of equipment to the
ground rod right on the outside of the basement wall.
You could always examine the quality of the grounding of the mike
cable shield. Some older mike cords had just a multi-strand wire
wrapped in one direction and not a hatch pattern wire shield. Some
aluminum foil shields don't make a good low impedance connection by
clamping. (Connections that can't be soldered are suspect).
Should have mentioned this earlier, but back in the day before I used
any computer interface, I had the problem with both a TT 705(?) mic
and a Heil Pro headset. Probably unlikely that both were defective.
73,
Carter K8VT
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
_______________________________________________
TenTec mailing list
TenTec@contesting.com
http://lists.contesting.com/mailman/listinfo/tentec
|