RE: [AMRadio] Tower Construction
I see that I left out a sentence. Lay the appropriate length radials in the ground for your RF ground return and bond them to the ring. I was thinking it but failed to type it in. Gary makes some good points about high impedance paths for lightning. I agree that lightning will not make several sharp turns through all the connections I described. Radials will help dissipate lightning and static charges but you can only connect several radials to each ground rod without making somewhat of a mess. The ring affords you a connection path for many more radials which will provide a better RF ground return if that's your goal. Many standard broadcast AM towers have ground radials configured this way. The bottom line is, there's a lot to consider when designing and building a ground system. Do a little research and don't rush into it. Figure out what will best serve you for your installation and do what you can afford. That's all from me for now. Best wishes! Best Regards, Steve White, W5SAW SW Commercial Electronics -Original Message- From: Gary Schafer [mailto:[EMAIL PROTECTED] Sent: Monday, June 12, 2006 9:26 PM To: 'Stevan A. White'; 'Ed Swynar'; 'Discussion of AM Radio' Subject: RE: [AMRadio] Tower Construction This affords you the opportunity to bond the tower, rebar, AND several copper clad ground rods together for the best possible DC ground for your tower. If you want an RF ground return for your installation, install a heavy duty copper ring and bond it to the ground rods. Best Regards, Steve White, W5SAW SW Commercial Electronics A good lightning ground is also a good RF ground. This means several radials should be installed along with the ground rods. A ring connecting ground rods around the tower does nothing for a lightning ground. The lowest impedance is in a straight line out away from the tower. A sharp turn at the junction of the ring to get over to the next ground rod in the ring looks like a high impedance path to the lightning as the sharp turn has considerable inductance. Also the other ground rods in the ring are already at the same potential as they are connected directly to the tower. The lightning will be carried out away from the tower in all directions. There will be no current carried by the ring connection so it is a waste of wire. The ground system would be better served by using that wire for another radial. 73 Gary K4FMX
Re: [Boatanchors] RE: [AMRadio] Tower Construction
I appreciate all the email on this subject. Interestingly, when lightning rods were placed on barns all over this country, I cannot recall any barn in our region ever catching on fire because of a lightning strike. I am sure that it did happen in other regions, particularly, in the Midwest/ The installation was to run a very large conductor cable from the lightning rod to the ground. There were generally two rods on either end of the roof. I would theorize that a lightning strike should be directed to a ground rod placed a few feet from the tower rather than to travel under the base of the tower as some have suggested. I am going to ground the tower at the three legs with a copper strap and then to a ground rod about 3 feet from the tower. Also, the Empire State Building and other skyscrapers get struck many times during a thunder storm and I wonder if anyone knows if the lightning travels through the superstructure or through cables/straps to the base of the building and through ground rods. Thanks Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com - the CRA Website Now with PayPal CRA Nets: 3805 Khz every Monday at 8 PM EST and 14255 every Saturday at 12 Noon EST - Original Message - From: Gary Schafer [EMAIL PROTECTED] To: 'Stevan A. White' [EMAIL PROTECTED]; 'Discussion of AM Radio' amradio@mailman.qth.net; [EMAIL PROTECTED] Sent: Monday, June 12, 2006 10:10 PM Subject: [Boatanchors] RE: [AMRadio] Tower Construction Be careful when giving this advice. A UFER ground is a good SUPLEMENTAL ground in a tower base but it should not be the only ground. A large area like a floor of a building provides more surface for the lightning to dissipate. A tower concrete foundation may not be large enough by itself and there is the possibility of poor connections inside so that the concrete crack from a lightning strike if it is the only ground connection. It is always recommended that ground rods be attached to each tower leg in addition. 73 Gary K4FMX DO RUN THE GROUND THROUGH THE CONCRETE! Take a look at the information on this site first though. You may be glad you did. http://www.scott-inc.com/html/ufer.htm Best Regards, Steve White, W5SAW SW Commercial Electronics -Original Message- From: Ed Swynar [mailto:[EMAIL PROTECTED] Sent: Saturday, June 10, 2006 2:16 PM To: Discussion of AM Radio; [EMAIL PROTECTED] Subject: Re: [AMRadio] Tower Construction Hi Dave, I have a 48' tall, tapered, self-supporting Delhi-brand tower --- 6 sections at 8' long each. The prescribed / manufacturer's recommendation is to bolt a 3' straight formed extention at the base of each leg (total of 3), to suspend these (a temporary wooden cradle will do admirably, as the cement sets) in a hole dug 4' square, 4-1/2' deep --- the cement is to come but a few inches below the bottom legs of the actual tower section. Oh yes --- the bottom 1' of the square hole is to be belled outward a foot, or so. The documentation says this is good for heights of up to 64', or so...I've never gone beyond 48', have never, EVER had an ounce of trouble in the two locations that I've had my tower up. BTW, the top of the tower as an old Cornell-Dubelier AR-44 rotator, a 3-element Hy-Gain TH3 MkIII triband yagi... Use industrial-grade coarse cement, do NOT run any ground leads through the block itself! ~73~ Eddy VE3CUI - VE3XZ ___ Boatanchors mailing list [EMAIL PROTECTED] http://mailman.qth.net/mailman/listinfo/boatanchors ** List Administrator - Duane Fischer, W8DBF/W9WZE ** ** For Assistance: [EMAIL PROTECTED] ** $$ For vintage radio info, see the HCI web site $$ http://www.w9wze.org
RE: [AMRadio] Tower Construction
I had lightning rods installed on my house, and has been a very good investment. Guy from Indiana comes down here in winter/early spring and installs them here in southern TN. Joe W4AAB - Original Message - From: david knepper [EMAIL PROTECTED] To: Gary Schafer [EMAIL PROTECTED]; 'Stevan A. White' [EMAIL PROTECTED]; 'Discussion of AM Radio' amradio@mailman.qth.net; [EMAIL PROTECTED] Sent: Tuesday, June 13, 2006 6:33 AM Subject: Re: [Boatanchors] RE: [AMRadio] Tower Construction I appreciate all the email on this subject. Interestingly, when lightning rods were placed on barns all over this country, I cannot recall any barn in our region ever catching on fire because of a lightning strike. I am sure that it did happen in other regions, particularly, in the Midwest/ The installation was to run a very large conductor cable from the lightning rod to the ground. There were generally two rods on either end of the roof. I would theorize that a lightning strike should be directed to a ground rod placed a few feet from the tower rather than to travel under the base of the tower as some have suggested. I am going to ground the tower at the three legs with a copper strap and then to a ground rod about 3 feet from the tower. Also, the Empire State Building and other skyscrapers get struck many times during a thunder storm and I wonder if anyone knows if the lightning travels through the superstructure or through cables/straps to the base of the building and through ground rods. Thanks Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com - the CRA Website Now with PayPal CRA Nets: 3805 Khz every Monday at 8 PM EST and 14255 every Saturday at 12 Noon EST - Original Message - From: Gary Schafer [EMAIL PROTECTED] To: 'Stevan A. White' [EMAIL PROTECTED]; 'Discussion of AM Radio' amradio@mailman.qth.net; [EMAIL PROTECTED] Sent: Monday, June 12, 2006 10:10 PM Subject: [Boatanchors] RE: [AMRadio] Tower Construction Be careful when giving this advice. A UFER ground is a good SUPLEMENTAL ground in a tower base but it should not be the only ground. A large area like a floor of a building provides more surface for the lightning to dissipate. A tower concrete foundation may not be large enough by itself and there is the possibility of poor connections inside so that the concrete crack from a lightning strike if it is the only ground connection. It is always recommended that ground rods be attached to each tower leg in addition. 73 Gary K4FMX DO RUN THE GROUND THROUGH THE CONCRETE! Take a look at the information on this site first though. You may be glad you did. http://www.scott-inc.com/html/ufer.htm Best Regards, Steve White, W5SAW SW Commercial Electronics -Original Message- From: Ed Swynar [mailto:[EMAIL PROTECTED] Sent: Saturday, June 10, 2006 2:16 PM To: Discussion of AM Radio; [EMAIL PROTECTED] Subject: Re: [AMRadio] Tower Construction Hi Dave, I have a 48' tall, tapered, self-supporting Delhi-brand tower --- 6 sections at 8' long each. The prescribed / manufacturer's recommendation is to bolt a 3' straight formed extention at the base of each leg (total of 3), to suspend these (a temporary wooden cradle will do admirably, as the cement sets) in a hole dug 4' square, 4-1/2' deep --- the cement is to come but a few inches below the bottom legs of the actual tower section. Oh yes --- the bottom 1' of the square hole is to be belled outward a foot, or so. The documentation says this is good for heights of up to 64', or so...I've never gone beyond 48', have never, EVER had an ounce of trouble in the two locations that I've had my tower up. BTW, the top of the tower as an old Cornell-Dubelier AR-44 rotator, a 3-element Hy-Gain TH3 MkIII triband yagi... Use industrial-grade coarse cement, do NOT run any ground leads through the block itself! ~73~ Eddy VE3CUI - VE3XZ ___ Boatanchors mailing list [EMAIL PROTECTED] http://mailman.qth.net/mailman/listinfo/boatanchors ** List Administrator - Duane Fischer, W8DBF/W9WZE ** ** For Assistance: [EMAIL PROTECTED] ** $$ For vintage radio info, see the HCI web site $$ http://www.w9wze.org __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
Re: [AMRadio] Tower Construction
Hi Steve, By running the ground through the concrete itself, do you not risk the potential of the block being damaged, should your tower suffer from a direct lightning strike...? Or is this merely another ...urban legend I've heard about tower installation, that has clung to the grey cells lo these many years...? Hi Hi ~73~ Eddy VE3CUI - VE3XZ - Original Message - From: Stevan A. White [EMAIL PROTECTED] To: 'Discussion of AM Radio' amradio@mailman.qth.net; [EMAIL PROTECTED] Sent: Sunday, June 11, 2006 11:32 PM Subject: RE: [AMRadio] Tower Construction DO RUN THE GROUND THROUGH THE CONCRETE! Take a look at the information on this site first though. You may be glad you did. http://www.scott-inc.com/html/ufer.htm Best Regards, Steve White, W5SAW SW Commercial Electronics -Original Message- From: Ed Swynar [mailto:[EMAIL PROTECTED] Sent: Saturday, June 10, 2006 2:16 PM To: Discussion of AM Radio; [EMAIL PROTECTED] Subject: Re: [AMRadio] Tower Construction Hi Dave, I have a 48' tall, tapered, self-supporting Delhi-brand tower --- 6 sections at 8' long each. The prescribed / manufacturer's recommendation is to bolt a 3' straight formed extention at the base of each leg (total of 3), to suspend these (a temporary wooden cradle will do admirably, as the cement sets) in a hole dug 4' square, 4-1/2' deep --- the cement is to come but a few inches below the bottom legs of the actual tower section. Oh yes --- the bottom 1' of the square hole is to be belled outward a foot, or so. The documentation says this is good for heights of up to 64', or so...I've never gone beyond 48', have never, EVER had an ounce of trouble in the two locations that I've had my tower up. BTW, the top of the tower as an old Cornell-Dubelier AR-44 rotator, a 3-element Hy-Gain TH3 MkIII triband yagi... Use industrial-grade coarse cement, do NOT run any ground leads through the block itself! ~73~ Eddy VE3CUI - VE3XZ - Original Message - From: david knepper [EMAIL PROTECTED] To: AMradio@mailman.qth.net; [EMAIL PROTECTED] Sent: Saturday, June 10, 2006 12:44 PM Subject: [AMRadio] Tower Construction I am thinking about buying a stick of Rohn 55G in cement with about 3 or 4 feet sticking out of the ground. I wonder how many sections of 55G I could mount without guys. I do have a strong base plate for the 55G but cementing a section seems to be sturdier. Any thoughts? Thanks Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com - the CRA Website Now with PayPal CRA Nets: 3805 Khz every Monday at 8 PM EST and 14255 every Saturday at 12 Noon EST __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
RE: [AMRadio] Tower Construction
Ed (and all), This may stir up a hornet's nest but the answer to your question is yes, if a ground wire is run from the leg of the tower through the concrete pad to a separate ground rod several feet away, that can be a problem. But the answer is also no, IF you use the Ufer method of grounding everything. If the rebar is tightly double wrapped, or tack welded (if you have the time and ability) and adequately bonded to the rest of the ground system, you won't have any problems. If the installation is sloppy and not enough attention is given to the bonding of the rebar inside the base pier, the spark gaps will light up and the intense discharges will indeed cause damage -- perhaps a few cracks, perhaps blow the thing completely apart. But when the system is installed properly, the concrete becomes part of the ground system. The following is a clip from http://www.scott-inc.com/html/ufer.htm: During World War II, a retired Vice President of Underwriters Laboratories, Herbert G. Ufer, developed it [the Ufer Grounding System] for the U.S. Army. Igloo shaped bomb storage vaults were being built, and possible static and lightning induced detonation problems were of concern. Ground conductivity was poor, and to be effective enough, ground rods would have to be driven several hundred feet. After much research and testing Mr. Ufer advised the Army to make connection to the steel bar that would internally reinforce the concrete foundation. He had determined that concrete was more conductive than all but the best soil, and that this improved semiconducting characteristic would enhance surface area contact with the surrounding soil. The wire ties normally used would be extra secure, and attention would be given to bonding or welding the lattice-type network together. The Army adopted the idea, and built the vaults as specified. After construction, ground resistance tests were made. No measurement exceeded five ohms. This value was considered extremely low for the local soil conductivity. Later tests confirmed stability. Mr. Ufer went on to develop the concept of concrete encased grounding electrodes. Many of his findings are detailed in IEEE Transactions paper # 63-1505. His system has since been used by the military, utility companies, Lake Tahoe lifts, and industry throughout the country. This site is only a brief introduction the concept. Google (or your favorite search engine) UFER and you'll come up with a whole lot more on it. I can almost guarantee that, if you read and understand about it, the next time you install a tower you'll want to do this. I installed an STL (Studio Transmitter Link) tower this way for a radio station I used to work for. I was the chief engineer for KGNC when the AM array had to be rebuilt and the STL tower got redone at the same time. I had never been too keen on wasting a section of tower by setting it into the ground. After all, that's what base plates were for. All to say, I learned that some tower installations are better served by a means for the tower to move and others not necessarily so. Short towers, a relative description I suppose, such as for most ham uses, are well served by the rigidity afforded by incorporating a section of the tower into the base support structure and some taut guy wires. This affords you the opportunity to bond the tower, rebar, AND several copper clad ground rods together for the best possible DC ground for your tower. If you want an RF ground return for your installation, install a heavy duty copper ring and bond it to the ground rods. Back to my STL tower; I never had another lightning or static discharge problem after putting up the 70' Rohn 25 tower this way. To address the original question posed I offer the same advice that Rohn used to publish in all their catalogs and literature. No tower is self-supporting at any height. (Unless it is manufactured to be a self-supporting tower.) Carefully consider how high you want to go, how much antenna will be catching the wind, and, can you sustain the loss if it was to occur? Thanks to those who stayed with me all the way through the explanation. I usually try to be more brief. (Hi Bob, you knew it was just a matter of time before I joined this list!) Best Regards, Steve White, W5SAW SW Commercial Electronics -Original Message- From: Ed Swynar [mailto:[EMAIL PROTECTED] Sent: Monday, June 12, 2006 6:14 AM To: Stevan A. White; 'Discussion of AM Radio'; [EMAIL PROTECTED] Subject: Re: [AMRadio] Tower Construction Hi Steve, By running the ground through the concrete itself, do you not risk the potential of the block being damaged, should your tower suffer from a direct lightning strike...? Or is this merely another ...urban legend I've heard about tower installation, that has clung to the grey cells lo these many years...? Hi Hi ~73~ Eddy VE3CUI - VE3XZ - Original Message - From: Stevan A. White [EMAIL PROTECTED] To: 'Discussion of AM Radio' amradio
RE: [AMRadio] Tower Construction
Be careful when giving this advice. A UFER ground is a good SUPLEMENTAL ground in a tower base but it should not be the only ground. A large area like a floor of a building provides more surface for the lightning to dissipate. A tower concrete foundation may not be large enough by itself and there is the possibility of poor connections inside so that the concrete crack from a lightning strike if it is the only ground connection. It is always recommended that ground rods be attached to each tower leg in addition. 73 Gary K4FMX DO RUN THE GROUND THROUGH THE CONCRETE! Take a look at the information on this site first though. You may be glad you did. http://www.scott-inc.com/html/ufer.htm Best Regards, Steve White, W5SAW SW Commercial Electronics -Original Message- From: Ed Swynar [mailto:[EMAIL PROTECTED] Sent: Saturday, June 10, 2006 2:16 PM To: Discussion of AM Radio; [EMAIL PROTECTED] Subject: Re: [AMRadio] Tower Construction Hi Dave, I have a 48' tall, tapered, self-supporting Delhi-brand tower --- 6 sections at 8' long each. The prescribed / manufacturer's recommendation is to bolt a 3' straight formed extention at the base of each leg (total of 3), to suspend these (a temporary wooden cradle will do admirably, as the cement sets) in a hole dug 4' square, 4-1/2' deep --- the cement is to come but a few inches below the bottom legs of the actual tower section. Oh yes --- the bottom 1' of the square hole is to be belled outward a foot, or so. The documentation says this is good for heights of up to 64', or so...I've never gone beyond 48', have never, EVER had an ounce of trouble in the two locations that I've had my tower up. BTW, the top of the tower as an old Cornell-Dubelier AR-44 rotator, a 3-element Hy-Gain TH3 MkIII triband yagi... Use industrial-grade coarse cement, do NOT run any ground leads through the block itself! ~73~ Eddy VE3CUI - VE3XZ
RE: [AMRadio] Tower Construction
This affords you the opportunity to bond the tower, rebar, AND several copper clad ground rods together for the best possible DC ground for your tower. If you want an RF ground return for your installation, install a heavy duty copper ring and bond it to the ground rods. Best Regards, Steve White, W5SAW SW Commercial Electronics A good lightning ground is also a good RF ground. This means several radials should be installed along with the ground rods. A ring connecting ground rods around the tower does nothing for a lightning ground. The lowest impedance is in a straight line out away from the tower. A sharp turn at the junction of the ring to get over to the next ground rod in the ring looks like a high impedance path to the lightning as the sharp turn has considerable inductance. Also the other ground rods in the ring are already at the same potential as they are connected directly to the tower. The lightning will be carried out away from the tower in all directions. There will be no current carried by the ring connection so it is a waste of wire. The ground system would be better served by using that wire for another radial. 73 Gary K4FMX
RE: [AMRadio] Tower Construction
From: david knepper [EMAIL PROTECTED] I am thinking about buying a stick of Rohn 55G in cement with about 3 or 4 feet sticking out of the ground. I wonder how many sections of 55G I could mount without guys. I do have a strong base plate for the 55G but cementing a section seems to be sturdier. If you are not going to use guys, you need to bury the base section. But if you do use guys, it would be sturdier to use the base plate, to allow the tower to sway and twist at the base during strong windstorms. That would relieve stress on the tower structure that would otherwise result from a base section rigidly mounted in concrete. That's why most large guyed towers use a base plate and pier pin. Don k4kyv
Re: [AMRadio] Tower Construction
Hi Dave, I have a 48' tall, tapered, self-supporting Delhi-brand tower --- 6 sections at 8' long each. The prescribed / manufacturer's recommendation is to bolt a 3' straight formed extention at the base of each leg (total of 3), to suspend these (a temporary wooden cradle will do admirably, as the cement sets) in a hole dug 4' square, 4-1/2' deep --- the cement is to come but a few inches below the bottom legs of the actual tower section. Oh yes --- the bottom 1' of the square hole is to be belled outward a foot, or so. The documentation says this is good for heights of up to 64', or so...I've never gone beyond 48', have never, EVER had an ounce of trouble in the two locations that I've had my tower up. BTW, the top of the tower as an old Cornell-Dubelier AR-44 rotator, a 3-element Hy-Gain TH3 MkIII triband yagi... Use industrial-grade coarse cement, do NOT run any ground leads through the block itself! ~73~ Eddy VE3CUI - VE3XZ - Original Message - From: david knepper [EMAIL PROTECTED] To: AMradio@mailman.qth.net; [EMAIL PROTECTED] Sent: Saturday, June 10, 2006 12:44 PM Subject: [AMRadio] Tower Construction I am thinking about buying a stick of Rohn 55G in cement with about 3 or 4 feet sticking out of the ground. I wonder how many sections of 55G I could mount without guys. I do have a strong base plate for the 55G but cementing a section seems to be sturdier. Any thoughts? Thanks Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com - the CRA Website Now with PayPal CRA Nets: 3805 Khz every Monday at 8 PM EST and 14255 every Saturday at 12 Noon EST __ AMRadio mailing list Home: http://mailman.qth.net/mailman/listinfo/amradio Help: http://mailman.qth.net/mmfaq.html Post: mailto:AMRadio@mailman.qth.net AMfone Website: http://www.amfone.net AM List Admin: Brian Sherrod/w5ami, Paul Courson/wa3vjb
Re: [AMRadio] Tower Construction
Dave: The G series towers weren't designed for self supporting installations. I looked at the Rohn site and it does not mention that parameter. http://www.rohnnet.net/rohnnet2004/html2004/index.html If you need a self supporting installation, might I suggest an HBX or HDBX. Rohn sold the H series towers to another company and I think this is it. http://www.trylon.com/home2.asp They are very sturdy and in all my years in commercial radio never saw one come down under design load conditions. At this next site is a bit of advertising showing the tower but it says Rohn still makes it. http://www.gsantenna.com/tower.htm , which I know is not correct. If nothing else, call Rohn and they will direct you to the manufacturer. I see used HBX at hamfests all the time for very reasonable prices, in fact one sold at Belton recently for about 100 dollars. It was the 40 ft. version, but one can buy additional sections to extend if needed. Most people do not know how good they are, therefore do not buy them. 73 Jim de W5JO - Original Message - From: David Knepper [EMAIL PROTECTED] To: Discussion of AM Radio amradio@mailman.qth.net; [EMAIL PROTECTED]; [EMAIL PROTECTED] Sent: Sunday, June 13, 2004 2:47 PM Subject: [AMRadio] Tower Construction I am contemplating placing a 10 foot section of Rohn 55G halfway in a cement base. Could someone suggest how many section could I add if the tower were self-supporting. Any suggestions would be appreciated. Thank you Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com ___ AMRadio mailing list AMRadio@mailman.qth.net http://mailman.qth.net/mailman/listinfo/amradio
Re: [AMRadio] Tower Construction
I know that with the Rohn 25G they recommend no more than three sections without guys. Not sure on the 55G, but it might be on someone's web site. I heard Rohn went out of business which is a D*n shame, in my opinion. They were a great company that has supplied great products for decades. Someone is probably now selling a cheap Chinese imitation made out of recycled pot metal and retailing for 90% of the Rohn price! On 13 Jun 2004 at 16:47, David Knepper wrote: I am contemplating placing a 10 foot section of Rohn 55G halfway in a cement base. Could someone suggest how many section could I add if the tower were self-supporting. Any suggestions would be appreciated. Thank you Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com ___ AMRadio mailing list AMRadio@mailman.qth.net http://mailman.qth.net/mailman/listinfo/amradio
Re: [AMRadio] Tower Construction
Don't know what book says. Been under impression for 40 years or more they were free standing (25G) up to 60 feet especially with a house bracket. I put one up at 55 ft in 1981, self supported with tri-bander, it is still here! and we have had several really high wind attacks, a nasty ice storm.. My book says no more than 60 feet without guys while constructing. The 135 footer I put up in 1965 had guys 60, 90, 120 feet.. it is still there! Don't know.. go figure! Mike K4XM I am contemplating placing a 10 foot section of Rohn 55G halfway in a cement base. Could someone suggest how many section could I add if the tower were self-supporting. Any suggestions would be appreciated. Thank you Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association --- Outgoing mail is certified Virus Free. Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.705 / Virus Database: 461 - Release Date: 6/12/2004
Re: [AMRadio] Tower Construction
Hi Brian, I am happy to report that Rohn and their products are not dead. A company called Radian bought out Rohn. See: http://www.rohnnet.com/ for more information. The best news is they are restarting the old Rohn manufacturing plant in the Peoria, Il. area. If I remember correctly someone else bought out Rohn's galvanizing facility here in the Peoria area. (I believe it was someone from the Chicago area but could stand to be corrected) So Radian is having this company do their galvanizing. (again this could stand to be corrected) This link will take you to the original Rohn catalog: http://www.rohnnet.net/rohnnet2004/html2004/index.html Hope this helps. How many of you remember that Rohn made a crank up tower?? I was interested in buying one a few years ago but when I called Rohn they would not admit having built one. I finally got some documentation on the one I was interested in. It was not rated very high for windload for it's size so I passed on it. Later I acquired a number of old QST's that had a number of ads in them for Rohn crank ups. They must have had some serious issues with them. 73 Larry WA9VRH - Original Message - From: Brian Carling [EMAIL PROTECTED] To: Discussion of AM Radio amradio@mailman.qth.net Sent: Sunday, June 13, 2004 5:11 PM Subject: Re: [AMRadio] Tower Construction I know that with the Rohn 25G they recommend no more than three sections without guys. Not sure on the 55G, but it might be on someone's web site. I heard Rohn went out of business which is a D*n shame, in my opinion. They were a great company that has supplied great products for decades. Someone is probably now selling a cheap Chinese imitation made out of recycled pot metal and retailing for 90% of the Rohn price! snip
Re: [AMRadio] Tower Construction
Thanks, Jim, for this information. Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com - Original Message - From: Jim Wilhite [EMAIL PROTECTED] To: Discussion of AM Radio amradio@mailman.qth.net Sent: Sunday, June 13, 2004 6:56 PM Subject: Re: [AMRadio] Tower Construction Dave: The G series towers weren't designed for self supporting installations. I looked at the Rohn site and it does not mention that parameter. http://www.rohnnet.net/rohnnet2004/html2004/index.html If you need a self supporting installation, might I suggest an HBX or HDBX. Rohn sold the H series towers to another company and I think this is it. http://www.trylon.com/home2.asp They are very sturdy and in all my years in commercial radio never saw one come down under design load conditions. At this next site is a bit of advertising showing the tower but it says Rohn still makes it. http://www.gsantenna.com/tower.htm , which I know is not correct. If nothing else, call Rohn and they will direct you to the manufacturer. I see used HBX at hamfests all the time for very reasonable prices, in fact one sold at Belton recently for about 100 dollars. It was the 40 ft. version, but one can buy additional sections to extend if needed. Most people do not know how good they are, therefore do not buy them. 73 Jim de W5JO - Original Message - From: David Knepper [EMAIL PROTECTED] To: Discussion of AM Radio amradio@mailman.qth.net; [EMAIL PROTECTED]; [EMAIL PROTECTED] Sent: Sunday, June 13, 2004 2:47 PM Subject: [AMRadio] Tower Construction I am contemplating placing a 10 foot section of Rohn 55G halfway in a cement base. Could someone suggest how many section could I add if the tower were self-supporting. Any suggestions would be appreciated. Thank you Dave, W3ST Publisher of the Collins Journal Secretary to the Collins Radio Association www.collinsra.com ___ AMRadio mailing list AMRadio@mailman.qth.net http://mailman.qth.net/mailman/listinfo/amradio ___ AMRadio mailing list AMRadio@mailman.qth.net http://mailman.qth.net/mailman/listinfo/amradio
Re: [AMRadio] Tower Construction
Larry: That is good news about Rohn. They have always made a quality product. The 25 series had the fold over option, of course, but the HB series could be cranked over. One would have to have a support pole with a winch and it hinged on two of the legs to lower it. The lowering was horizontal not vertical. I had my set up this way and it worked just fine. The legs were fitted with thick walled pipe and one removed the bolts on one of the legs, then one of the bolts on the other two legs. With proper cable and a winch, you could lower the tower. I hope to have mine back in operation soon. I have a Mosley TA-53M on top with a Hygain 400 rotor. The rotor plate was, of course, and option and bottom mounted. They had that plate back when the rotor was manufactured by Hygain. Sure has been through a lot of storms and both have survived. I have the HBDX 40 and would like to add the next section, but that would require changing the leg supports and saddles for the fold over. If I remember right, the 25 series catalog recommended only about 25 ft. above a house bracketed with about 6-8 sq. ft. of antenna maximum, but that is poor memory talking. As Brian mentioned they can be loaded much more than that and survive. Glad they are back. 73 Jim de W5JO - Original Message - From: Larry Saletzki [EMAIL PROTECTED] To: [EMAIL PROTECTED]; Discussion of AM Radio amradio@mailman.qth.net Sent: Sunday, June 13, 2004 7:28 PM Subject: Re: [AMRadio] Tower Construction Hi Brian, I am happy to report that Rohn and their products are not dead. A company called Radian bought out Rohn. See: http://www.rohnnet.com/ for more information. The best news is they are restarting the old Rohn manufacturing plant in the Peoria, Il. area. If I remember correctly someone else bought out Rohn's galvanizing facility here in the Peoria area. (I believe it was someone from the Chicago area but could stand to be corrected) So Radian is having this company do their galvanizing. (again this could stand to be corrected) This link will take you to the original Rohn catalog: http://www.rohnnet.net/rohnnet2004/html2004/index.html Hope this helps. How many of you remember that Rohn made a crank up tower?? I was interested in buying one a few years ago but when I called Rohn they would not admit having built one. I finally got some documentation on the one I was interested in. It was not rated very high for windload for it's size so I passed on it. Later I acquired a number of old QST's that had a number of ads in them for Rohn crank ups. They must have had some serious issues with them. 73 Larry WA9VRH - Original Message - From: Brian Carling [EMAIL PROTECTED] To: Discussion of AM Radio amradio@mailman.qth.net Sent: Sunday, June 13, 2004 5:11 PM Subject: Re: [AMRadio] Tower Construction I know that with the Rohn 25G they recommend no more than three sections without guys. Not sure on the 55G, but it might be on someone's web site. I heard Rohn went out of business which is a D*n shame, in my opinion. They were a great company that has supplied great products for decades. Someone is probably now selling a cheap Chinese imitation made out of recycled pot metal and retailing for 90% of the Rohn price! snip ___ AMRadio mailing list AMRadio@mailman.qth.net http://mailman.qth.net/mailman/listinfo/amradio
Re: [AMRadio] Tower Construction
Yep, so I've heard. Making crankups must be like making ladders, half the cost is insurance. The one I have is about 40 ft. and is 3 sections of aluminum tower with steel shit in between for the pulleys. Most of them were rusted and it cost me a fortune to have new ones welded up. Still a cheap tower compared with new. My main tower is 55' Rohn 25 with the tilt-over in the middle. Chickenshits like me don't climb! But Rohn finally quit making these cuz too many dumbshits didn't follow instructions and den dey fall down go boom. Bob - Original Message - From: Larry Saletzki [EMAIL PROTECTED] To: [EMAIL PROTECTED]; Discussion of AM Radio amradio@mailman.qth.net Sent: Sunday, June 13, 2004 7:28 PM Subject: Re: [AMRadio] Tower Construction Hi Brian, I am happy to report that Rohn and their products are not dead. A company called Radian bought out Rohn. See: http://www.rohnnet.com/ for more information. The best news is they are restarting the old Rohn manufacturing plant in the Peoria, Il. area. If I remember correctly someone else bought out Rohn's galvanizing facility here in the Peoria area. (I believe it was someone from the Chicago area but could stand to be corrected) So Radian is having this company do their galvanizing. (again this could stand to be corrected) This link will take you to the original Rohn catalog: http://www.rohnnet.net/rohnnet2004/html2004/index.html Hope this helps. How many of you remember that Rohn made a crank up tower?? I was interested in buying one a few years ago but when I called Rohn they would not admit having built one. I finally got some documentation on the one I was interested in. It was not rated very high for windload for it's size so I passed on it. Later I acquired a number of old QST's that had a number of ads in them for Rohn crank ups. They must have had some serious issues with them. 73 Larry WA9VRH - Original Message - From: Brian Carling [EMAIL PROTECTED] To: Discussion of AM Radio amradio@mailman.qth.net Sent: Sunday, June 13, 2004 5:11 PM Subject: Re: [AMRadio] Tower Construction I know that with the Rohn 25G they recommend no more than three sections without guys. Not sure on the 55G, but it might be on someone's web site. I heard Rohn went out of business which is a D*n shame, in my opinion. They were a great company that has supplied great products for decades. Someone is probably now selling a cheap Chinese imitation made out of recycled pot metal and retailing for 90% of the Rohn price! snip ___ AMRadio mailing list AMRadio@mailman.qth.net http://mailman.qth.net/mailman/listinfo/amradio
