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Alsworld
| | Posted on Sunday, July 20, 2003 - 2:43 pm: | 
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Tech833,
I just got my IMAX 2000 up yesterday but have more work to do. Here's what's up.
Base of the antenna (feedpoint) is at 55ft, going up to approx 79ft. It is snaked up through a very tall pine tree. The tree still still towers a good 20 ft higher. I dropped it a few times at a different location trying to do things by myself. Trashed my GPK bracket but it's nothing a hammer and vice won't fix. Currently I have no way to get the GPK on unless I can get that high SAFELY. I'll work that issue when I have an option.
My question is grounding the antenna pole. I have the antenna bracket well grounded to the top of the support pole. At the bottom, I have two 8ft copper grounding rods to ground the antenna system. I have plenty of 1/2" tinned braid to ground the pole to one rod, then another. I would like your opinion on how far to space these. Should I bury the grounding braid or does it matter? Should the braid go from the antenna support pole to one grounding rod, then to the other grounding rod, or can they both be connceted with the antenna pole, something like a "V" or triangle?
Thanks.
Alsworld |
Ironmask
| | Posted on Sunday, July 20, 2003 - 8:51 pm: |
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Alsworld,
Because you didn't answer my E-Mail I shouldn't answer your question BUT, being the kind of guy I am.
Based on experience; One ground rod at the base of the tree. Four ground rods equal distance from base rod and apart. Mine are 20' from base. Connect all together [all five]. Run a connector from base rod to shack ground rod. It is also code and better to run a connector to circuit breaker panel ground rod. I ran 4 [0000 solid] copper wire burried 2' below ground level [ wife and kids can't try to mow it]. This set up works for many good reasons. Read your antenna book to find out why. E-Mail me!! Iron Mask |
Bigbob
| | Posted on Monday, July 21, 2003 - 6:21 am: |
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See if you can get a local lumberjack to top that tree for you,he'll have the right equipment,and you'll have lots of campfire wood,nothing like the smell of pine burning in a campfire.Be sure to seal the stub to prevent parasites,then strap on that 2000 and gpk and you're good to go.Don't worry about lightning,with or without the top your antenna system is toast,if direct hit.A man had his in a 130 foot pine with one grnd.rod vertical and 9 horizontal and 3 00 ground wires,the ground system is in perfect shape but the tree is dead and the lightning followed the coax to the house and completely gutted his radio room,oh and the ant. is in a million pieces,so for performance reasons you can't get to much ground,but for lightning,put a baggie on the connector and toss it out the window before storm hits,or carry very good house insurance. |
Alsworld
| | Posted on Monday, July 21, 2003 - 7:43 pm: |
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Darn Ironmask, I'm duck the spears, flames, knuckleballs, arrows and all that you are shooting my way...LOL!  I must have missed the e-mail (I get so much spam I get a little crazy with the delete button), but I'll shoot you one right after this message.
Bigbob, that is my only concern is lightning following the coax back into the shack. I am no longer in a lightning prone area like Florida, but it still occurs. The antenna will never survive a strike being it's a big fiberglass stick, but the shack and all associated equipment (which is worth much more than the antenna) is my concern. I will fully comply on tossing the coax end out the window during any storms. Man I sure don't need any house fires! I love this hobby but it's not worth that for sure.
I'm mainly looking for performance reasons, but will always be cautious concering lightning.
I have a third grounding rod I'll use for the shack equipment. Although I never remember any previous serious lightning storms up this way, if I start to see even one, at least a lightning arrestor will be in order. And I'll still throw the connector out the window!
Thanks for the replies.
Alsworld |
Tech833
| | Posted on Tuesday, July 22, 2003 - 12:45 am: |
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With two rods, the only thing you have to worry about is getting them too close to one-another, so they don't cancel each other out. If you were to bury one rod at the base of the tree and then another about 10 feet away, that would be just fine. Run the ground wire from the antenna down the tree to the first rod, then either across the ground, or under ground to the second rod.
To keep lightning from coming down your coax into the shack, use a Polyphasor. That will stop the lightning cold. |
Twa77
| | Posted on Saturday, July 26, 2003 - 1:23 pm: |
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what is a polyphasor and who has them |
Alsworld
| | Posted on Sunday, July 27, 2003 - 1:13 am: |
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Twa77,
I was able to find the product at http://www.polyphaser.com
It has like 17 pages of different applications for the CB frequencies, although not all fit what we need (covering different freqs). I found what I was looking for on page 7 or 10 I think, but have not contacted them yet for prices.
Neat stuff.
Alsworld
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Kc0gxz
| | Posted on Sunday, July 27, 2003 - 3:00 pm: |
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Alsworld--Bigbob
Just so you know, I am NOT a antenna expert by any stretch of the imagination. But I do know this.
You can ground your masting or tower from here to doomes day and it WILL NOT protect any antenna that is capacitance grounded.
Rarely does a glass antenna take a direct hit from lightning. When a hit does accure, normally it is your tower or the mast directly under the antenna that takes the hit. Any antenna that is capacitance grounded will be history in less than a millisecond after a hit.
Don't misunderstand me. The grounding of your complete station however is something that should definately be done. All I am saying is that no amount of grounding will save a glass antenna.
But grounded or not, EVERYONE should get in the habit of disconnecting their coax when their station is not in use. Replacing an antenna is a whole lot cheaper than replacing a complete station.
Bottom line... Grounding should be considered a must, but NEVER completely rely on grounding to protect you from a lightning hit. Lightning is just too unpredictible.
Big bob. Did you drop out of here for awhile? I didn't see any of your posts for a few days. Or maybe I just missed them.
73s my friends.
Jeff, kc0gxz. |
Alsworld
| | Posted on Monday, July 28, 2003 - 12:17 am: |
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Jeff, good points for sure. Yeah I realize that a fiberglass stick will be history, but at the cost, I am willing to sacrifice it and do whatever it takes to save all the other expensive stuff connected to the other end of the coax (in the shack). I fully concur with you and Bigbob, disconnect always when lightning is around. Take no chances. Same reason I run a surge protector for all the shack equipment, but I still unplug it when disconnecting the coax. I made a habit of that completly isolating my equipment from any electrical surge. Makes good sense.
Good points Jeff. Thanks for your information. And where did Bigbob go? Must have had a good weekend .
Alsworld |
Tech833
| | Posted on Tuesday, July 29, 2003 - 9:10 pm: |
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I am not saying that disconnecting when lightning comes around would be a waste of your time. With that said...
Do you think that radio technicians feverishly scurry up to the mountain tops every time there is a lightning storm and disconnect all the equipment until it is over? Of course not.
How do you think that commercial radio equipment on high level, lightning succeptable sites can take multiple lightning strikes in one night and stay on the air year after year regardless of the severity of the storms? Polyphasor and grounding.
Why is it so hard for some operators to understand? It is not magic. It is technology that has been around and has been proven for over 50 years. A polyphasor isolates the coax center conductor and passes charges to ground. It is the same thing as disconnecting your coax to anything below design frequency (like lightning).
I give up. Do not buy a Polyphasor. Remember to disconnect your radio cables every time there is a lightning storm. Give your neighbors the key top your house so if you are away on vacation and a lightning storm comes in, they can go do it for you. Or, drop 50 bucks on a Polyphasor and do what the commercial radio ops do- forget about it.
If lightning hits your antenna, it may blow up. So what? You want to keep the lightning from coming inside your shack, right? Buy a Polyphasor!
P.S. I had to edit this message to add this- A Polyphasor is NOT the same thing as a 'lightning arrestor'. Lightning arrestors are usually some sort of spark gap unit or similar. A Polyphasor actually breaks the coax center conductor and only allows radio frequencies above X to pass. Big difference.
One last thing- I apologize for the sarcasm in my above post. My frustration is showing. I am going to take a vacation from the forums for a few more days. |
Kc0gxz
| | Posted on Tuesday, July 29, 2003 - 11:30 pm: |
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Tech833
Actually, I didn't take it as sarcasm. I found it quite vigorating. Maybe you should let loose a little more often if that's what it takes to get your point across to some (like me) people.
However, I don't understand how it is that I never heard of a Polyphasor until I read your Tuesday's, July 22 post, unless they were/are only available to the Broadcast and Comercial industry. This is all new to me.
I gotta have a couple of these.
And you think we don't learn anything from Tech833 on the Copper Forum? For shame, for shame!! I have learned a lot of neat things from every one of Copper's Techs. Also from some of these sharp members that are here too.
Don't ever think your time has been wasted with us 833. You're just one of the reasons I stay with Copper's forum.
Jeff, kc0gxz.
PS: I understand your frustration. I apologize 833 if I have been one of the attributing factors.
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Alsworld
| | Posted on Wednesday, July 30, 2003 - 1:23 am: |
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Tech833, I love it man!!! No BS, straight answer with an explaination. You are the expert, so please keep giving us the straight scoop on this. I can understand your frustration, however I am also the one seeking advice (this area is not my expertise so hence, I ask you). I really appreciate your advice, and when we get stupid, keep us in line man!
I realize it takes much of your time, which you do not get paid for, and after your own job and family time to answer our questions. Frustration is to be expected at some of our 'ignorant' statements or questions. Heck, I say take out your frustrations here when things go too far (except I would ask to not be so hard on those newbies that haven't a clue). N/A on this thread.
Keep up the good work Tech833. You are doing your best at teaching us. What else can we ask for???
Thank you.
Alsworld |
Taz
| | Posted on Thursday, July 31, 2003 - 3:43 am: |
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Thats how I like my answers, just how you gave it. Straight up with constructive sarcasm which really isnt sarcasm to me. But more of a form of constructive critisizm. Thanks 833.
Taz |
Tech833
| | Posted on Monday, August 04, 2003 - 11:36 am: |
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Thank you for the support!
The problem rests squarely with me. I am not accustomed to 'dealing with the public'. I am used to dealing with other engineers alone. I do not have time for social activities (having a life) so my only human contact is usually other engineers. If another engineer ever told me to forget about the fancy Polyphasor, just disconnect the coax whenever a lightning storm comes through, I would politely fire them on the spot and make them walk home without water.
When someone on this helpful forum says the same thing, I am not accustomed to reasoning with them using typed words. I usually prefer to simply give up on that thread and move to another area of the forum where I can be of assistance with less frustration. I am not saying that 'it's my way or the highway', I am saying that if someone who is less experienced in an area than myself is telling me I am wrong, since I do not have the time for the resultant back and forth dialogue to prove myself, I simply let them think whatever they wish and remove myself from the thread before I waste even more time for little or no gain.
Then... There are times like this when instead of leaving, I chose to 'fire back'. Unfortunately, I was not really being supportive but only blowing off steam. I'm glad it was taken in the proper context in this case. Usually it is not. Actually, most of the time when I do this, the Forum Master either edits it out or refuses to approve the post. This particular section of the forum does not require my posts to be approved first (they post as soon as I click 'go'), so it got posted as typed.
Sometimes my own frustration guides me in the proper path. Sometimes it does not. This time, I guess I got lucky. |
Kc0gxz
| | Posted on Tuesday, August 05, 2003 - 1:28 am: |
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Tech833
Lol. It could be worse Steve.
If you were our professor in a college, you would probably wanna jap-slap us around until your words finally sink in.
But I can understand. I think what is happening here is that some people will click on to a certain portion of the forum and read maybe the last couple of posts without reading all of them first. And sometimes the "Subject" gets changed midway somewhere along the line. Maybe that's one of the reasons for the "repeated" questions.
You can sometimes find the same question asked in 3 different sections of the forum by 3 different people but worded in 3 different ways.
Oh yeah, I understand your occasional frustration. But feel free to do what you HAVE to do or say to get your point across.
Hang in there Teck833. You're worth your weight in gold around here as far as I'm concerned.
73s.
Jeff. |
Tech833
| | Posted on Tuesday, August 05, 2003 - 9:24 pm: |
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Thanks. By today's prices, I should be worth around $62,202.50 if I adjust for today's closing trend. |
Kc0gxz
| | Posted on Tuesday, August 05, 2003 - 9:48 pm: |
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Tech833
$62,202? Oh Oh. I may have spoken a little hastily there.
$62,202 huh? Hmmmm. Lol. I wonder what that works out to in bronze.
Oh heck. What am I saying? I still couldn't afford you!!!
Jeff.
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Bigbob
| | Posted on Monday, August 11, 2003 - 7:43 pm: |
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DOES ANY ONE HAVE A BALLPARK FIGURE ON A POLYPHAZOR SORRY I'M NOT YELLING JUST TO TIRED TO WORK THIS KEYBOARD,MADE 10 MISTAKES ON THE WORD I'M, COL. |
Tech808
| | Posted on Monday, August 11, 2003 - 7:58 pm: |
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Bigbob,
I think Tech833 told me they were around 50 or 60 dollars.
I am sure he can give you the right price on them.
And, over the weekend the Forummaster and I talked and he is checking on handleing them for the Copper Customers.
Lon
Tech808 |
Tech833
| | Posted on Tuesday, August 12, 2003 - 1:29 am: |
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List price is either $64 or $69 depending on the model.
Ask the Forum Master if Copper is going to carry them. I think they may. |
Alsworld
| | Posted on Monday, August 11, 2003 - 9:14 pm: |
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That would be excellent! Cheap price for a sure fire lightning stopper. They had so many versions, but only a few fit the "typical" CB setup with UHF connectors on either side and covering our frequency range.
I must assume that it is attached or grounded to the stations grounding point (such as a grounding rod)?
Good news Copper is looking into these. Please let us know Forum Master if it looks like a go (or not).
Alsworld |
Taz
| | Posted on Tuesday, August 12, 2003 - 9:30 am: |
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Tech833.
Your telling me that rasio stations rely on a 70 dollar inline coax device to save their equipment from lightning? |
Tech833
| | Posted on Tuesday, August 12, 2003 - 11:15 am: |
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Al,
The Polyphasor is usually located where the coax enters the building and it is also normally mounted to the copper grounding bar at the same location. The grounding bus bar is routed to the main ground system.
Taz. Yes. That's what I have been trying to tell everyone. |
Scrapiron63
| | Posted on Tuesday, August 12, 2003 - 12:34 pm: |
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833, i'm old and slow, but have been reading this quite a bit, and am I right or wrong, when you get a lightning hit, your mostly depending on the grounding system of your antenna and tower to dissipate the charge, but the Polyphasor is the safety net that catches the perchange of the charge not going to ground, and coming thur the coax. If you have a poorly grounded antenna mounted on your roof, like so many do, and lightning hits it, it might knock a hole in your roof, but the polyphasor will save your radio equipment. It's really hard to properly gound an antenna on a roof anyway.
Lightning does some crazy things, a friend called a couple nights ago looking for an amplifier. Last week, Ligntning hit his antenna, he had an A-99 on a pushup, the pushup was pushed into the ground, and he had a ground rod strapped to the pushup. It splintered the A-99, all his eqipment was hooked up at the time, it went in on the coax, burned up his wattmeter, and the next thing in line, which was a Texas Star 350, but from there, didn't hurt his radio or a 50 amp power supply that was hooked to the Texas star. His radio is a mobil, galaxy 88, didn't hurt it or the 12 amp supply hooked to it. He did have everything inside grounded to an outside ground rod. A tech had checked the wattmeter and amp, said they were not worth repairing, now thats odd it didn't get the other equipment.
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Taz
| | Posted on Tuesday, August 12, 2003 - 5:55 pm: |
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Well, I have EVERYTHING in my house grounded radio wise but my meter. Otherwise everything is grounded and it only costed me 3 bucks.
Scrapiron,
Lightning is really weird, it's notorious for those things. |
Tech833
| | Posted on Tuesday, August 12, 2003 - 8:45 pm: |
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Lightning takes the path of least resistance. At that instant, the path of least resistance between the earth and the cloud was through the air,A99, coax, meter, amp, then ground.
The Polyphasor breaks the connection between your coax center conductor. Then, the path of least resistance no longer includes your equipment inside the building.
Commercial radio sites take hits all the time. It is so common that we tend to not think about it much anymore. |
Bigbob
| | Posted on Saturday, August 16, 2003 - 5:57 pm: |
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Is it possible to post a schematic or diagram of the polyphazor,or do you have a cut-away view of it,I hope. |
Taz
| | Posted on Saturday, August 16, 2003 - 6:43 pm: |
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Actually Tech833,
Most things if not everything on this planet takes the path of least resistance.
Just a side note.
Taz |
Crazyfrenchmen
| | Posted on Saturday, August 16, 2003 - 7:24 pm: |
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Ive have alway's used a glass jar when a storm comes around i just unhook the coax from back of radio an set it in the jar.an knock on wood ive never had any problems.any opion on this ideal. Dan |
Tech833
| | Posted on Tuesday, August 19, 2003 - 11:39 am: |
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The guy who runs that DX ring website and has that beacon uses a Polyphasor- http://www.dxring.net/11beacon.htm
It is mounted on a hilltop. Ask him if it works.
Crazyfrenchmen,
I already discussed this. Not everyone is willing to be home, awake, and remember to go disconnect the coax and put the end in a glass jar when a lightning storm comes around. What would happen if you were not home?
I think that post was meant as bait. Just in case it was not, then you have my answer. |
Crazyfrenchmen
| | Posted on Wednesday, August 20, 2003 - 8:48 am: |
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TECH 833,
as far as reading or seeing your post i have never seen it.i have only been on the form just a few month's. so u must had post it before my time. an as far as BAIT iam not sure what u mean about that!! i started useing cb's back in the 70's an i was told about this trick with the jar back then.probly way befor the polyphazor was even thought of.i just cant see spending $60.00 to 70.00 for an item that a $2 jar will do the same thing. but each there own. Dan |
Tech833
| | Posted on Wednesday, August 20, 2003 - 11:52 am: |
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The Polyphasor has been around since the 60's. The concept has been around since the 30's.
Just because one has not 'heard of' a technology does not mean it does not exist.
Professional two way radio technicians would not dream of the glass jar idea. To each his/her own. Most people do not have the time or desire to babysit their coax connectors every minute of their lives. Professionals rely on technology to solve problems. |
Kc0gxz
| | Posted on Wednesday, August 20, 2003 - 6:32 pm: |
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Tech833
I don't think you can make it any clearer than that!! You sure answered any Polyphasor questions I may have had. Hopefully everyone elses too.
Jeff, kc0gxz. |
Tech808
| | Posted on Wednesday, August 20, 2003 - 6:57 pm: |
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Well as soon as the Forummaster can get a deal on the Polypahsor's, and offer them to the member's I will have to order 4 of them.
Gives me time to start saving for them.
2 - for the SE Beams
1 - for the 305
1 - for the NEW ? 
Lon
Tech808 |
Tech833
| | Posted on Wednesday, August 20, 2003 - 11:15 pm: |
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I should point out that putting all four of them inline with the same antenna will not gain added protection.
Look! I made a joke. |
Taz
| | Posted on Wednesday, August 20, 2003 - 9:29 pm: |
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I dont think Lon has made a post without a smiley face.
Do you smile like that all the time? |
Bullet
| | Posted on Wednesday, August 20, 2003 - 11:42 pm: |
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i like the idea of the polyphaser as stated you might not be home for the jar thing!
and i can personaly say this method works fine when your home BUT ive had 3 radios this last year damaged by lightning hits while i was at work.
so fellas thats the next thing going inline here as im down to my last radio now
i do have a question about them though. how many hits will a polyphaser take and would you need to replace one every so many hits? or do they work like a timex and just keep ticking.haha |
Tech808
| | Posted on Thursday, August 21, 2003 - 12:56 am: |
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Taz,
NO!
Actually, I am just like the Bumper Sticker I have on our cars and truck's.
MARINES
YOUR BEST FRIEND!
YOUR WORST ENEMY!
Semper Fi
Lon |
Tech833
| | Posted on Thursday, August 21, 2003 - 5:12 pm: |
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Bullet,
A Polyphasor is not like those gas tube surge supressors which have limited use capability. A Polyphasor should last the rest of your life. If not, they are inexpensive to replace. |
Bullet
| | Posted on Thursday, August 21, 2003 - 9:01 pm: |
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cool thats all i need to know thanks 833 |
Xlaxx
| | Posted on Sunday, August 31, 2003 - 10:44 pm: |
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Tech 833-
Can lightning arc out of a glass pickle jar?
I remembered that Tech 307 made a post on this topic some time ago and suggested the use of a jar. Does the pickle jar actually insulate the lightening from going anywhere inside someone's shack or can it arc out of it?
How is the polyphasor connected to the coax?
I use the pickle jar method and disconnect the coax when going 10-7.
Thanks
XLAXX |
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