[Repeater-Builder] Re: follow up on lightening strike last spring response
Rich, it sounds like an antenna, feedline, or tower/site issue. The easiest way to find out would be a dummy load connected in place of your antenna. Operate into the repeater locally with an ht and listen for any noise. What you're describing is a fairly common problem with repeaters that share an antenna for tx/rx. How was the antenna Tested? A simple vswr test usually won't reveal this sort of problem. Its usually caused by loose metal-metal contact in close proximity of the antenna. However anything's possible :) 73 and good luck. Dan K8PLW Livonia, MI --- In Repeater-Builder@yahoogroups.com, Richard rra...@... wrote: Sorry if I've been late in posting. First, the antenna and hard line is ok. We've tested that part out and its working. We think ( I ) that we got zapped through a unused phone line which is mounted behind the repeater rack. Yes, we have tested the can's using both a IRL (?sp) and a General Dynamics service monitor. They were taken apart and cleaned and retuned. Everything indicated they were functioning normally. Till we put them back in service. I don't know if they were tested with a dummy load. The technicians made many trips to the site: the technicians worked for the company that we rent the site from. We replaced all of the connectors and only found one that had scorched indications on it, but that was all. I asked if any of you knew how to find out if a can was operational, because all the test equipment that was used indicated they were ok. We finally found a workable solution. We added a fifth can, tuned to the transmit freq. That stoped the crackling noise. Now we're going to replace the can's, and go with a 6 can configuration. this is what was reconmended by the technician. Rich K8JX www.w8usa.org
[Repeater-Builder] Re: follow up on lightening strike last spring response
Most duplexers are passive, mechanical devices. You did say the cavities had been visually inspected and cleaned so we can assume the cans themselves are fine. In my opinion the single component on a duplexer that's most likely to fail would be the cable harness and its associated connectors/adaptors. Is this a vhf repeater? What is the power output? Dan K8PLW Livonia, MI --- In Repeater-Builder@yahoogroups.com, Richard rra...@... wrote: Sorry if I've been late in posting. First, the antenna and hard line is ok. We've tested that part out and its working. We think ( I ) that we got zapped through a unused phone line which is mounted behind the repeater rack. Yes, we have tested the can's using both a IRL (?sp) and a General Dynamics service monitor. They were taken apart and cleaned and retuned. Everything indicated they were functioning normally. Till we put them back in service. I don't know if they were tested with a dummy load. The technicians made many trips to the site: the technicians worked for the company that we rent the site from. We replaced all of the connectors and only found one that had scorched indications on it, but that was all. I asked if any of you knew how to find out if a can was operational, because all the test equipment that was used indicated they were ok. We finally found a workable solution. We added a fifth can, tuned to the transmit freq. That stoped the crackling noise. Now we're going to replace the can's, and go with a 6 can configuration. this is what was reconmended by the technician. Rich K8JX www.w8usa.org
[Repeater-Builder] RE: follow up on lightening strike last spring response
Sorry if I've been late in posting. First, the antenna and hard line is ok. We've tested that part out and its working. We think ( I ) that we got zapped through a unused phone line which is mounted behind the repeater rack. Yes, we have tested the can's using both a IRL (?sp) and a General Dynamics service monitor. They were taken apart and cleaned and retuned. Everything indicated they were functioning normally. Till we put them back in service. I don't know if they were tested with a dummy load. The technicians made many trips to the site: the technicians worked for the company that we rent the site from. We replaced all of the connectors and only found one that had scorched indications on it, but that was all. I asked if any of you knew how to find out if a can was operational, because all the test equipment that was used indicated they were ok. We finally found a workable solution. We added a fifth can, tuned to the transmit freq. That stoped the crackling noise. Now we're going to replace the can's, and go with a 6 can configuration. this is what was reconmended by the technician. Rich K8JX www.w8usa.org
Re: [Repeater-Builder] RE: follow up on lightening strike last spring response
Richard (and everyone else), I just uploaded a file called antenna_pix.pdf to the group. Our local group had an antenna that was real noisy when duplexed but worked great otherwise. We spent months trying to fix the issue then decided to replace the antenna. Just goes to show noise issues could be anywhere. I hate tower rats! Jim WA2RJP - Original Message - From: Richard To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 17, 2010 13:47 Subject: [Repeater-Builder] RE: follow up on lightening strike last spring response Sorry if I've been late in posting. First, the antenna and hard line is ok. We've tested that part out and its working. We think ( I ) that we got zapped through a unused phone line which is mounted behind the repeater rack. Yes, we have tested the can's using both a IRL (?sp) and a General Dynamics service monitor. They were taken apart and cleaned and retuned. Everything indicated they were functioning normally. Till we put them back in service. I don't know if they were tested with a dummy load. The technicians made many trips to the site: the technicians worked for the company that we rent the site from. We replaced all of the connectors and only found one that had scorched indications on it, but that was all. I asked if any of you knew how to find out if a can was operational, because all the test equipment that was used indicated they were ok. We finally found a workable solution. We added a fifth can, tuned to the transmit freq. That stoped the crackling noise. Now we're going to replace the can's, and go with a 6 can configuration. this is what was reconmended by the technician. Rich K8JX www.w8usa.org
Re: [Repeater-Builder] RE: follow up on lightening strike last spring response
Something from left field: Does the nose have any pattern to it? My UHF seems to have site noise that is possibly generated by a 2.4g digital spread spectrum controller. At first, it seemed like it was regular but I found that a TV stationg jput this system in at the same time I changed to a new repeater package and 2 bay half wave spaced UHF Comprod commercial dipole. Frustrating to say the least but just a thought. Brian - Original Message - From: Richard To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 17, 2010 10:47 AM Subject: [Repeater-Builder] RE: follow up on lightening strike last spring response Sorry if I've been late in posting. First, the antenna and hard line is ok. We've tested that part out and its working. We think ( I ) that we got zapped through a unused phone line which is mounted behind the repeater rack. Yes, we have tested the can's using both a IRL (?sp) and a General Dynamics service monitor. They were taken apart and cleaned and retuned. Everything indicated they were functioning normally. Till we put them back in service. I don't know if they were tested with a dummy load. The technicians made many trips to the site: the technicians worked for the company that we rent the site from. We replaced all of the connectors and only found one that had scorched indications on it, but that was all. I asked if any of you knew how to find out if a can was operational, because all the test equipment that was used indicated they were ok. We finally found a workable solution. We added a fifth can, tuned to the transmit freq. That stoped the crackling noise. Now we're going to replace the can's, and go with a 6 can configuration. this is what was recommended by the technician. Rich K8JX www.w8usa.org
[Repeater-Builder] RE: follow up on lightening strike last spring
I know its been a long time since I first posed the question on what might be causing the noise we were experiencing after being hit by lightening. After many trips to the Technical shop for testing, we replaced the repeater ( was a vertex 5000, now a Icom ur2000) and are in process of checking out controllers. The duplexers were my big worry. And yes, it would seem that concern wasn't unfounded. We started experiencing a degradation on the receive side of the repeater and then, a leakage from the cans. We had the duplexers checked out with two different service monitors and found nothing! The technician who works on duplexers took ours apart and found only a little bit of carbon, but that was it. they checked out ok. We put them back into service and the noise was there making communications impossible. We are now going to replace them with a 6 configuration instead of the four we have been using. My question to the list is, besides the noise factor and crackling noise, is there any other methode of discovering if the can's are bad or not? Yes, I did and have been losing sleep over this one. I also wish to thank Kevin and the group for all their feedback on my question I put in last summer. You helped more than you know. Rich Ranta K8JX www.w8usa.org
Re: [Repeater-Builder] RE: follow up on lightening strike last spring
Rich, you didn't mention the antenna, cable and jumpers. What did you do there? JIM On Sat, Jan 16, 2010 at 6:12 PM, Richard rra...@sbcglobal.net wrote: I know its been a long time since I first posed the question on what might be causing the noise we were experiencing after being hit by lightening. After many trips to the Technical shop for testing, we replaced the repeater ( was a vertex 5000, now a Icom ur2000) and are in process of checking out controllers. The duplexers were my big worry. And yes, it would seem that concern wasn't unfounded. We started experiencing a degradation on the receive side of the repeater and then, a leakage from the cans. We had the duplexers checked out with two different service monitors and found nothing! The technician who works on duplexers took ours apart and found only a little bit of carbon, but that was it. they checked out ok. We put them back into service and the noise was there making communications impossible. We are now going to replace them with a 6 configuration instead of the four we have been using. My question to the list is, besides the noise factor and crackling noise, is there any other methode of discovering if the can's are bad or not? Yes, I did and have been losing sleep over this one. I also wish to thank Kevin and the group for all their feedback on my question I put in last summer. You helped more than you know. Rich Ranta K8JX www.w8usa.org -- Jim Cicirello 181 Stevens Street Wellsville, N.Y. 14895 (585)593-4655
Re: [Repeater-Builder] RE: follow up on lightening strike last spring
Are these pass-reject cans with capacitors that might have been damaged? Matthew Kaufman
Re: [Repeater-Builder] RE: follow up on lightening strike last spring
I bought a set of cans that took a lightning hit years ago on my 2 meter repeater. They are older Phelps Dodge cans. The finger stock was OK, but the tuning rod had arched. I retuned the low pass cans to high pass and vice versa. They have worked fine ever since, but I do run them at low power, 50 watts. You might try the same thing. 73, Joe, K1ike Richard wrote: My question to the list is, besides the noise factor and crackling noise, is there any other methode of discovering if the can's are bad or not? Yes, I did and have been losing sleep over this one.
Re: [Repeater-Builder] RE: follow up on lightening strike last spring
Since your chief complaint is noise, you need to define the noise. Noise in repeaters can be from MANY other sources besides duplexers. Sure your cans *might* be at fault, but if you're not having desense issues, I would not suspect them right off. Is there anything loose on the tower? What kind of antenna are you using? Is it broke inside? Is anyone else at the site having noise issues, or just you? Is there anything loose on the tower as a result of the lightning? (burnt off grounds, etc.) Is there a PolyPhaser or similar device in the line that might be causing trouble? Will the repeater duplex into a dummy load with no noise? If so, your problem is not in the repeater, interconnect cables, or duplexer. It's in your feedline or antenna. Lightning can do funny things to antennas and feedline that are not readily visible to the eye without disassembly. Busted antennas can cause noise VERY easily. (for obvious reasons) If it *will* duplex into a dummy load without noise, take a dummy load to the top of the tower and see if it duplexes OK in that configuration. If it works with the load in place, your looking at a busted antenna or loose, broken, cracked tower hardware or grounds. Good luck, Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531 Richard wrote: I know its been a long time since I first posed the question on what might be causing the noise we were experiencing after being hit by lightening. After many trips to the Technical shop for testing, we replaced the repeater ( was a vertex 5000, now a Icom ur2000) and are in process of checking out controllers. The duplexers were my big worry. And yes, it would seem that concern wasn't unfounded. We started experiencing a degradation on the receive side of the repeater and then, a leakage from the cans. We had the duplexers checked out with two different service monitors and found nothing! The technician who works on duplexers took ours apart and found only a little bit of carbon, but that was it. they checked out ok. We put them back into service and the noise was there making communications impossible. We are now going to replace them with a 6 configuration instead of the four we have been using. My question to the list is, besides the noise factor and crackling noise, is there any other methode of discovering if the can's are bad or not? Yes, I did and have been losing sleep over this one. I also wish to thank Kevin and the group for all their feedback on my question I put in last summer. You helped more than you know. Rich Ranta K8JX www.w8usa.org Yahoo! Groups Links No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.432 / Virus Database: 270.14.146/2627 - Release Date: 01/16/10 19:35:00
Re: [Repeater-Builder] RE: follow up on lightening strike last spring
Do you get the same crackling noise with the duplexer attached to a dummy load? a ground mounted antenna with different feedline? 73 Glenn WB4UIV At 06:12 PM 1/16/2010, you wrote: I know its been a long time since I first posed the question on what might be causing the noise we were experiencing after being hit by lightening. After many trips to the Technical shop for testing, we replaced the repeater ( was a vertex 5000, now a Icom ur2000) and are in process of checking out controllers. The duplexers were my big worry. And yes, it would seem that concern wasn't unfounded. We started experiencing a degradation on the receive side of the repeater and then, a leakage from the cans. We had the duplexers checked out with two different service monitors and found nothing! The technician who works on duplexers took ours apart and found only a little bit of carbon, but that was it. they checked out ok. We put them back into service and the noise was there making communications impossible. We are now going to replace them with a 6 configuration instead of the four we have been using. My question to the list is, besides the noise factor and crackling noise, is there any other methode of discovering if the can's are bad or not? Yes, I did and have been losing sleep over this one. I also wish to thank Kevin and the group for all their feedback on my question I put in last summer. You helped more than you know. Rich Ranta K8JX www.w8usa.org Yahoo! Groups Links
Re: [Repeater-Builder] RE: follow up on lightening strike last spring
At 1/16/2010 15:12, you wrote: I know its been a long time since I first posed the question on what might be causing the noise we were experiencing after being hit by lightening. After many trips to the Technical shop for testing, we replaced the repeater ( was a vertex 5000, now a Icom ur2000) and are in process of checking out controllers. The duplexers were my big worry. And yes, it would seem that concern wasn't unfounded. We started experiencing a degradation on the receive side of the repeater and then, a leakage from the cans. We had the duplexers checked out with two different service monitors and found nothing! The technician who works on duplexers took ours apart and found only a little bit of carbon, but that was it. they checked out ok. We put them back into service and the noise was there making communications impossible. We are now going to replace them with a 6 configuration instead of the four we have been using. My question to the list is, besides the noise factor and crackling noise, is there any other methode of discovering if the can's are bad or not? Yes, I did and have been losing sleep over this one. We don't get much lightning out here in SoCal (now having said that we're due for a week of very nasty weather, so maybe time to catch up?), but of the few incidents I'm aware of, the lightning damaged either the antenna or feedline in such a way that the antenna system continued to perform well w.r.t. VSWR gain, but considerable noise was generated whenever the antenna system was driven with RF. My advise is to try a different antenna/feedline at the site see if your desense goes away. Bob NO6B
