Re: [Repeater-Builder] crackle in a repeater tower
Short of tightening all the leg joints, I don't know about finding the source of this type problem, but I have seen AM broadcast towers with copper jumpers wired across the leg joints to help prevent the same type of problem. The jumpers were connected with ring terminals soldered to copper braid, and the ring terminals were screwed to the legs with stainless steel sheet metal screws. The jumpers weren't weather proofed, oddly enough. I don't know if the jumpers were installed with the tower or if they were a cure for a problem that occurred after installation. At 01:12 AM 3/22/2006, you wrote: Hi guys .Is there a way that you can locate loose bolts or fittings in a tower by having a transmitter txing on the tower and checking the tower with a spectrum anayzler with a beam for interference on other frequencies .I have a tower that crackles through VHF repeaters that are operating on the site and sometimes it affects uhf repeaters on site as well but i still havent found where it is coming from .It has to be something loose as it is worst on windy days any sugestions would be great Thank You, Ian Wells, Kerinvale Comaudio, http://www.kerinvalecomaudio.com.au/www.kerinvalecomaudio.com.au Thanks, Robin Midgett K4IDC VHF+ Glutton EM66se Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * To unsubscribe from this group, send an email to: [EMAIL PROTECTED] * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] crackle in a repeater tower
I am observing the same phenomenon on a 2 meter repeater in my area. You'll find it interesting that the BD-224 was just replaced, however on "windy days" the repeater sensitivity gives way to that crackling noise that you referred to. My theory, which will be tested soon, is that due to poor grounding static charges build up in the antenna due to the effects of high velocity wind. Our plan is to install grounding kits on the coax at the antenna and on the ground near the gas tube. All grounds will be at the same point as much as is possible. Stay in touch with me for the result of this experiment. YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
Hi Ian, Have you tried a different antenna. Verticals get that way as they get older due to cracked solder joints. Al Romeo, Michigan - Original Message - From: Ian Wells To: Repeater-Builder@yahoogroups.com Sent: Wednesday, March 22, 2006 2:12 AM Subject: [Repeater-Builder] crackle in a repeater tower Hi guys .Is there a way that you can locate loose bolts or fittings in a tower by having a transmitter txing on the tower and checking the tower with a spectrum anayzler with a beam for interference on other frequencies .I have a tower that crackles through VHF repeaters that are operating on the site and sometimes it affects uhf repeaters on site as well but i still havent found where it is coming from .It has to be something loose as it is worst on windy days any sugestions would be great Thank You, Ian Wells, Kerinvale Comaudio, www.kerinvalecomaudio.com.au YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
Did I say BD-224? I think everyone knows what I mean. YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
KE4ADV What you propose should be practice and not an experiment. It is just good practice to ground the antenna mast, coax and equipment to a common ground. Otherwise where I am located in West Florida the setup might last a month due to lightning. You should also use double shielded coax or hardline for your coax run and in your equipment. 73's de Tom Manning, AF4UG - Original Message - From: [EMAIL PROTECTED] To: Repeater-Builder@yahoogroups.com Sent: Wednesday, March 22, 2006 8:33 AM Subject: Re: [Repeater-Builder] crackle in a repeater tower I am observing the same phenomenon on a 2 meter repeater in my area. You'll find it interesting that the BD-224 was just replaced, however on "windy days" the repeater sensitivity gives way to that crackling noise that you referred to.My theory, which will be tested soon, is that due to poor grounding static charges build up in the antenna due to the effects of high velocity wind. Our plan is to install grounding kits on the coax at the antenna and on the ground near the gas tube. All grounds will be at the same point as much as is possible.Stay in touch with me for the result of this experiment. YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
Of, you are correct Tom. But when one is a guest on a tower one does not always have the luxury of demanding certain specifications. We do what we have to do to demonstrate our gratitude. Now back to the issue being discussed. It might even be argued that if "cracking" is observed, something somewhere may not be as resilient to the effects of lightning as it should be. YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
Thanks guys for the returns .With earthing the coaxes does it help eliminate the static from the tower Thank You, Ian Wells, Kerinvale Comaudio, www.kerinvalecomaudio.com.au YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
I will not declare for a matter of fact that this will solve your problem, but it cannot hurt. Each section of the tower and any antennas should all be tied into the site grounding system. If EVERYTHING at the site is at the same ground potential, preferably a buried grid, resilience to lightning is dramatically improved. Even fences and propane tanks should be considered in your grounding system. Sometimes it's all in the details. YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
Thanks I will look into it Thank You, Ian Wells, Kerinvale Comaudio, www.kerinvalecomaudio.com.au ---Original Message--- From: [EMAIL PROTECTED] Date: 03/23/06 02:19:58 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] crackle in a repeater tower I will not declare for a matter of fact that this will solve your problem, but it cannot hurt. Each section of the tower and any antennas should all be tied into the site grounding system. If EVERYTHING at the site is at the same ground potential, preferably a buried grid, resilience to lightning is dramatically improved. Even fences and propane tanks should be considered in your grounding system. Sometimes it's all in the details. YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
We are using rg223 as fly leads and heliax up to the antennas .I feel it is a loose bolt in the tower and it moves when the tower twists .apart from checking each bolt .What I was wondering with earthing the coax at the top and bottom of the tower was if it tends to improve the shielding of the heliax so it ignores Any static on the way up the tower .One other thing I might be overlooking is one repeater on site had its ant damaged due to lightning and it could be the cause of the static but the users of that repeater don't find any problems with their reception at all .Its affecting everyone else though which is strange . Thank You, Ian Wells, Kerinvale Comaudio, www.kerinvalecomaudio.com.au ---Original Message--- From: Tom Manning Date: 03/23/06 00:51:53 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] crackle in a repeater tower KE4ADV What you propose should be practice and not an experiment. It is just good practice to ground the antenna mast, coax and equipment to a common ground. Otherwise where I am located in West Florida the setup might last a month due to lightning. You should also use double shielded coax or hardline for your coax run and in your equipment. 73's de Tom Manning, AF4UG YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
At 01:57 PM 03/22/06, you wrote: We are using rg223 as fly leads and heliax up to the antennas .I feel it is a loose bolt in the tower and it moves when the tower twists .apart from checking each bolt .What I was wondering with earthing the coax at the top and bottom of the tower was if it tends to improve the shielding of the heliax so it ignores Any static on the way up the tower .One other thing I might be overlooking is one repeater on site had its ant damaged due to lightning and it could be the cause of the static but the users of that repeater don't find any problems with their reception at all .Its affecting everyone else though which is strange. This article may be of interest: http://www.repeater-builder.com/antenna/cracking.html Is that lightning-damaged antenna used in a duplex situation? If not, then the users of it won't see a problem. Some local sites use a shared receive antenna and separate transmit antennas. Our prime UHF system uses a single 406-512MHz antenna at 120' feeding a Sinclair window filter - 5 or 6 separate passbands that feed different repeaters, 440-446MHz for amateur receive, the rest in commercial bands all the way up to 507mhz. The commercial repeater transmitters are combined, 5 to each antenna. Some of the amateur repeater transmitters are combined, some are on their own antennas. A while back one of the commercial combined antennas developed an intermittent crack and it was a real pain to find... Thank You, Ian Wells, Kerinvale Comaudio, www.kerinvalecomaudio.com.au No problem, Ian. Please let us know what you find... Mike Morris WA6ILQ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
Re: [Repeater-Builder] crackle in a repeater tower
Yesthere is3 VHF 70mhz duplex repeaters and 2 470mhz duplex repeaters on the site. 2 of the VHF repeaters have a problem with the crackles and the repeater with the damaged ant doesn't have any where near the problem however their coverage range isn't as good as the other two (good ants )so maybe that's why it doesn't get affected as much .If I replace this ant with a new one they will proberly get the same problem . Thank You, Ian Wells, Kerinvale Comaudio, www.kerinvalecomaudio.com.au ---Original Message--- From: Mike Morris WA6ILQ Date: 03/23/06 09:46:47 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] crackle in a repeater tower At 01:57 PM 03/22/06, you wrote: We are using rg223 as fly leads and heliax up to the antennas .I feel it is a loose bolt in the tower and it moves when the tower twists .apart from checking each bolt .What I was wondering with earthing the coax at the top and bottom of the tower was if it tends to improve the shielding of the heliax so it ignores Any static on the way up the tower .One other thing I might be overlooking is one repeater on site had its ant damaged due to lightning and it could be the cause of the static but the users of that repeater don't find any problems with their reception at all .Its affecting everyone else though which is strange.This article may be of interest: http://www.repeater-builder.com/antenna/cracking.htmlIs that lightning-damaged antenna used in a duplex situation? If not, then the users of it won't see a problem.Some local sites use a shared receive antenna and separate transmit antennas.Our prime UHF system uses a single 406-512MHz antenna at 120' feeding a Sinclair window filter - 5 or 6 separate passbands that feed different repeaters, 440-446MHz for amateur receive, the rest in commercial bands all the way up to 507mhz. The commercial repeater transmitters are combined, 5 to each antenna. Some of the amateur repeater transmitters are combined, some are on their own antennas. A while back one of the commercial combined antennas developed an intermittent crack and it was a real pain to find... Thank You,Ian Wells,Kerinvale Comaudio,www.kerinvalecomaudio.com.auNo problem, Ian. Please let us know what you find...Mike Morris WA6ILQ YAHOO! GROUPS LINKS Visit your group "Repeater-Builder" on the web. To unsubscribe from this group, send an email to:[EMAIL PROTECTED] Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.
