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Penrider
Junior Member
Username: Penrider

Post Number: 10
Registered: 1-2007
Posted on Thursday, January 25, 2007 - 10:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I see that the question of whether or not to ground the actual Radio has been answered....but, what is the best part of the actual radio/amp/meters to hook the ground wire to?...I currently just have the antenna grounded with an inline lightning arrestor on the coax at the antenna end...hook the ground to the so-239's on the radios, or what??
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Tech808
Moderator
Username: Tech808

Post Number: 12849
Registered: 8-2002


Posted on Thursday, January 25, 2007 - 11:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Penrider,

Run an 18 gauge wire with a Hole connector on one end to the CASE SCREW on each Radio, Meter, Amp, Antenna Switches, everything and run them all to a single point ground with your antenna, Poly Phasers, ground rods, tower or pole.

Hope this help's,
Lon
Tech808
CEF#808/HAM#33
CVC#002
N9CEF
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2364
Registered: 9-2004


Posted on Friday, January 26, 2007 - 12:07 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

penrider, any metal case screw on the piece of equipment you are grounding.

as for where to hook all the grounds and such:

first off, get rid of that lightning arrestor.
it will not protect your equipment from a strike, and it wont handle much power either.
if you want to be protected from a strike, tehn you need to get a polyphaser which is about $60.00.

using solid copper wire at least 10ga.; connect one end to the bolts that attatch your antenna to the mast, and the other end to an 8 ft. ground rod pounded all the way into the ground at the base of the mast. connect the bottom of the mast to the ground rod too.
now you will need another 8ft. ground rod pounded in right outside the wall where your equipment sits.
it needs to be close enough so that the total length of wire running from this ground rod to your equipment is less than 7 feet.
run a solid copper wire from the ground rod to a ground bus bar (you can buy these at lowes for a few bucks), and go from the bus bar to the various pieces of radio equipment.
everything in line that has a metal chassis should be connected to the ground bus bar.
remember to keep the total length of wire from your station's ground rod to the equipment to less than 7 feet. (long explanation, just trust me)

now you need to run a wire from the ground rod at the base of your mast to the ground rod you pounded in outside the radio room.
this wire can be any length that it takes to get from one rod to the other, and it can be buried a few inches down to avoid a trip/ mower hazard.

last but certainly not least, you need to run a wire from the electrical box feeding the house to whichever of your ground rods is closer, doesnt matter which since they are all connected.
connect this wire to the metal housing of the box or to the ground wire coming out of the box if it is accessible.

now you have a single point ground and all the wires from your equipment to ground are less than 7 feet long.

good luck,
matt
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Tech237
Moderator
Username: Tech237

Post Number: 690
Registered: 4-2004
Posted on Friday, January 26, 2007 - 9:02 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Whoa! Do NOT remove the lightning protector. Yes it will not help with a direct strike - nothing will - but it does help with close hits and after all it is better to be safe than sorry. THe best thing during a storm is to disconnect the radios and ground the center of the coax.

I have used lightning protectors from cheap generic ones to Polyphasers for over 30 years and have yet to lose a radio to a lightning strike. As Hyperno can attest Australia has some tremendous storms at times. As an example in 88 my parents house was hit by two simultaneous strikes - one to the tv antenna and one to the power line. We lost every light bulb in the house (several now soldered into the sockets), 3 feet of RG-11 coax from the antenna to the coupler, the coupler itself, and my PC. My radios (all with a generic protector in line) were not damaged, and neither was the tv - which had an inbuilt protector.

Yes I agree with Kid in that you should use the best, which Polyphase if, but if that is beyond your budget than use what you can afford and ground the coax during a storm. This way at the worst, you'll lose the coax and not a radio.

Simon
Tech237
KD7IEB

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Tech237
Moderator
Username: Tech237

Post Number: 691
Registered: 4-2004
Posted on Friday, January 26, 2007 - 9:11 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Oh yeah for awhile I ran home made lightning protectors made from spark plugs.

Simon
Tech237
KD7IEB

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Penrider
Junior Member
Username: Penrider

Post Number: 11
Registered: 1-2007
Posted on Saturday, January 27, 2007 - 1:07 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

thanks for the help...that's kinda what I thought to do, but wasn't sure...as far as the 7ft from the ground rod, I can't because my setup is over 10ft from the nearest wall..make it 12ft to where I could drive another rod...will this hurt much?...I think I understand why, the whole closest path to ground theory....btw, spark plug??...never thought of that one..prolly works tho....thanks again
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Slugo4449
Intermediate Member
Username: Slugo4449

Post Number: 158
Registered: 7-2004
Posted on Saturday, January 27, 2007 - 1:40 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I am so glad no one brought up the old wives tale or urban legend that you just have to discommect the coax and put it in a mason jar full of water.

I hear guys locally telling others that is how to protect from a lightening strike.

Can you imagine the damage if you did this and got a full strike?

73, Marty
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Kid_vicious
Senior Member
Username: Kid_vicious

Post Number: 2366
Registered: 9-2004


Posted on Sunday, January 28, 2007 - 11:29 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

oh man, slugo!
dont bring up the mason jar here! LOL
we have many threads discussing the dangers of that old wives tale!

simon,

my reasoning for getting rid of the lightning arrestor is people trust these things and buy them thinking that it will protect them.
they are wrong, and could get killed thinking like that.

you have to remember that the typical setup of a CB'er is one that consists of compromises, and without the knowledge to know which compromises you CAN make and which ones you shouldnt; the typical new radio operator incorrectly assumes that they have found a good deal. (instead of paying for a polyphaser, they only had to spend $5.00)

simon, take a look at SINKER's pictures in the members pic area to see what happens to these things when you try and run a KLV1000 through it.

are you seeing where im coming from yet?
you see, we CB'ers are going to put that cheapie arrestor in line somewhere and forget about it.
then we are going to upgrade our station, get a big amp, and either blow up the amp, the arrestor, or both.
or worse yet, we are going to damage the arrestor to the point where our SWR is now high and we are slowly damaging our equipment.
THAT is why i tell everyone to just get rid of it and be done with it.
(we both know that those "arrestors" were put on the market to make money, not save lives)

do you really think that if his antenna took a direct hit, that the little arrestor that cant handle 1,000 watts is going to protect him?
and if its an indirect hit, then having the whole house and station properly grounded will take care of that.

also remember that the arrestors you can buy today are NOTHING like the ones produced 20 years ago.
they are much more cheaply made and SHOULD NOT be trusted. IMO

slugo, the reasoning behind keeping the ground wires coming from your equipment shorter than 7 feet is because 8.5 feet is 1/4 wavelength at CB freqs. and therefore your ground wire will try to act like an antenna causing all kinds of nasty problems and can even cause you to get shocked by your mic!
maybe time to consider moving the radio shack.
this grounding stuff is a big deal.
matt

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