Re: 80m KPA1500 High reflected power problems **SOLVED!**
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Re: 80m KPA1500 High reflected power problems **SOLVED!**
 
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Hi folks,
FOUND THE PROBLEM....Maybe?? I have a 30 foot vertical ground-plane style antenna that I use for diversity RX on 40 and 80, which was connected to the AUX antenna port. This was being overloaded by the QRO power from the TX antenna feedpoints just a few feet laterally and 40-50' higher vertically. As soon as I disconnected this antenna the problem went away. NOTE that the problem only occurred on the lower CW portions of both 80 *and 40*, as I found out tonight. In the SSB sections, even on CW transmit, there were no problems. But as I said, disconnecting the diversity AUX antenna solved the High SWR amp fault. So now, the big question, is there some form of filtering within the K3s to disable receive on the AUX line during transmit, or do I have to look into a second "front end protector" device as I have on my K9AY loop connected to the RX IN port. Or perhaps some other valid solution? At least I'm glad I finally have full operation back on 40 and 80! - pjd ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Lovin' my K3S (S/N 10023)
73, Peter W2IRT |
Re: 80m KPA1500 High reflected power problems **SOLVED!**
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Well, there's one final, further item to add to this. I've almost certainly destroyed my sub receiver. It's not completely deaf, but very, very, very close to it. Signals that are in the noise on VFO-B are S9 on VFO-A on the same frequency.
Anything I can do to test this out? With Bouvet coming soon (hopefully) I'm really hoping to have a working radio to work this ultra rare one. The risk of another 4 or 5 weeks of down time is very depressing at this stage. - pjd -----Original Message----- From: Peter Dougherty <[hidden email]> Sent: Monday, March 11, 2019 1:33 AM To: '[hidden email]' <[hidden email]> Subject: RE: [Elecraft] 80m KPA1500 High reflected power problems **SOLVED!** Hi folks, FOUND THE PROBLEM....Maybe?? I have a 30 foot vertical ground-plane style antenna that I use for diversity RX on 40 and 80, which was connected to the AUX antenna port. This was being overloaded by the QRO power from the TX antenna feedpoints just a few feet laterally and 40-50' higher vertically. As soon as I disconnected this antenna the problem went away. NOTE that the problem only occurred on the lower CW portions of both 80 *and 40*, as I found out tonight. In the SSB sections, even on CW transmit, there were no problems. But as I said, disconnecting the diversity AUX antenna solved the High SWR amp fault. So now, the big question, is there some form of filtering within the K3s to disable receive on the AUX line during transmit, or do I have to look into a second "front end protector" device as I have on my K9AY loop connected to the RX IN port. Or perhaps some other valid solution? At least I'm glad I finally have full operation back on 40 and 80! - pjd ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Lovin' my K3S (S/N 10023)
73, Peter W2IRT |
Re: 80m KPA1500 High reflected power problems **SOLVED!**
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In reply to this post by Peter W2IRT
I am not sure how a second antenna effects the amplifier, I believe that
the K3(S) has a safeguard from some overload conditions. If your RX antenna is close to your TX and you run HP, I would protect your transceiver from overload by either shorting the RX feedline during TX or with a protector such as this one: https://www.dxengineering.com/parts/dxe-rg-5000 John KK9A PETER DOUGHERTY W2IRT wrote: ------------------------- Hi folks, FOUND THE PROBLEM....Maybe?? I have a 30 foot vertical ground-plane style antenna that I use for diversity RX on 40 and 80, which was connected to the AUX antenna port. This was being overloaded by the QRO power from the TX antenna feedpoints just a few feet laterally and 40-50' higher vertically. As soon as I disconnected this antenna the problem went away. NOTE that the problem only occurred on the lower CW portions of both 80 *and 40*, as I found out tonight. In the SSB sections, even on CW transmit, there were no problems. But as I said, disconnecting the diversity AUX antenna solved the High SWR amp fault. So now, the big question, is there some form of filtering within the K3s to disable receive on the AUX line during transmit, or do I have to look into a second "front end protector" device as I have on my K9AY loop connected to the RX IN port. Or perhaps some other valid solution? At least I'm glad I finally have full operation back on 40 and 80! ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: 80m KPA1500 High reflected power problems **SOLVED!**
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In reply to this post by Peter W2IRT
On 3/10/2019 10:33 PM, Peter Dougherty wrote:
> I have a 30 foot vertical ground-plane style antenna that I use for diversity RX on 40 and 80, which was connected to the AUX antenna port. This was being overloaded by the QRO power from the TX antenna feedpoints just a few feet laterally and 40-50' higher vertically. As soon as I disconnected this antenna the problem went away. Hi Peter, It sounds to me like your station (and maybe your home) is not properly bonded. All of your feedlines SHOULD be bonded to a common ground at lightning arrestors where they enter your shack, all the equipment in your shack SHOULD be bonded together and to all of the grounds in your home including that one, power, telco, CATV, and satellite. If you've done this, disconnecting one of the antennas from your rig should not change anything on the transmit side -- the only change should be overload of the second RX by that antenna. Two good references on grounding and bonding. One is N0AX's recent ARRL book on the topic. The second is the set of slides for talks I've done at Pacificon and Visalia on the topic. http://k9yc.com/GroundingAndAudio.pdf 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: 80m KPA1500 High reflected power problems **SOLVED!**
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In reply to this post by john@kk9a.com
I have that exact front-end protector on the main RX line from the K9AY, but
I didn't have it on the AUX antenna. I will now, obviously. - pjd -----Original Message----- From: [hidden email] <[hidden email]> On Behalf Of [hidden email] Sent: Monday, March 11, 2019 1:58 PM To: [hidden email] Subject: Re: [Elecraft] 80m KPA1500 High reflected power problems **SOLVED!** I am not sure how a second antenna effects the amplifier, I believe that the K3(S) has a safeguard from some overload conditions. If your RX antenna is close to your TX and you run HP, I would protect your transceiver from overload by either shorting the RX feedline during TX or with a protector such as this one: https://www.dxengineering.com/parts/dxe-rg-5000 John KK9A PETER DOUGHERTY W2IRT wrote: ------------------------- Hi folks, FOUND THE PROBLEM....Maybe?? I have a 30 foot vertical ground-plane style antenna that I use for diversity RX on 40 and 80, which was connected to the AUX antenna port. This was being overloaded by the QRO power from the TX antenna feedpoints just a few feet laterally and 40-50' higher vertically. As soon as I disconnected this antenna the problem went away. NOTE that the problem only occurred on the lower CW portions of both 80 *and 40*, as I found out tonight. In the SSB sections, even on CW transmit, there were no problems. But as I said, disconnecting the diversity AUX antenna solved the High SWR amp fault. So now, the big question, is there some form of filtering within the K3s to disable receive on the AUX line during transmit, or do I have to look into a second "front end protector" device as I have on my K9AY loop connected to the RX IN port. Or perhaps some other valid solution? At least I'm glad I finally have full operation back on 40 and 80! ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Lovin' my K3S (S/N 10023)
73, Peter W2IRT |
Re: 80m KPA1500 High reflected power problems **SOLVED!**
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In reply to this post by Jim Brown-10
I've got my bonding about as good as I can get it for the moment, although
I'm probably going to do some improvements this year. The lightning arrestors are built in to the RCS-12 antenna switchbox (RCS-12L with the gas discharge tubes), and everything's bonded at the base of the tower. There's a single feedline coming inside from that tower-mounted switchbox. Each piece of radio gear and the computer inside is bonded by 1" braid going to a copper bus. LAN and voice line comms are not, however the connection from the pole is fiber, not copper so that's not likely a problem. The copper bus inside is bonded to a ground rod outside the shack, which in turn is bonded to the tower ground system. The deficiency is that the copper bus is not grounded to the same point as the tower, since the tower is about 50 feet away from the shack. I guess I could run a 50 or 60' run of 2" strapping from the desk, through the floor, across the crawlspace, and out the conduit to the tower, but I suspect that might be more a hindrance than a help, quite honestly. - pjd -----Original Message----- From: [hidden email] <[hidden email]> On Behalf Of Jim Brown Sent: Monday, March 11, 2019 2:18 PM To: [hidden email] Subject: Re: [Elecraft] 80m KPA1500 High reflected power problems **SOLVED!** On 3/10/2019 10:33 PM, Peter Dougherty wrote: > I have a 30 foot vertical ground-plane style antenna that I use for diversity RX on 40 and 80, which was connected to the AUX antenna port. This was being overloaded by the QRO power from the TX antenna feedpoints just a few feet laterally and 40-50' higher vertically. As soon as I disconnected this antenna the problem went away. Hi Peter, It sounds to me like your station (and maybe your home) is not properly bonded. All of your feedlines SHOULD be bonded to a common ground at lightning arrestors where they enter your shack, all the equipment in your shack SHOULD be bonded together and to all of the grounds in your home including that one, power, telco, CATV, and satellite. If you've done this, disconnecting one of the antennas from your rig should not change anything on the transmit side -- the only change should be overload of the second RX by that antenna. Two good references on grounding and bonding. One is N0AX's recent ARRL book on the topic. The second is the set of slides for talks I've done at Pacificon and Visalia on the topic. http://k9yc.com/GroundingAndAudio.pdf 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Lovin' my K3S (S/N 10023)
73, Peter W2IRT |
Re: 80m KPA1500 High reflected power problems **SOLVED!**
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On 3/11/2019 1:40 PM, Peter Dougherty wrote:
> I've got my bonding about as good as I can get it for the moment, although > I'm probably going to do some improvements this year. The lightning > arrestors are built in to the RCS-12 antenna switchbox (RCS-12L with the gas > discharge tubes), and everything's bonded at the base of the tower. The function of GDTs is to offer some protection of equipment in the event of a strike. To do that, they must be close to the equipment, not at the tower. Lightning can induce a lot of current on the coax between the tower and the shack. I suggest that you add arrestors (including that vertical you use for RX) where all of your coax enters the shack, bond them to your rod(s), and to the shack bonding. That's probably the missing bonding that I suspected! Also, what about bonding to the power entry panel? > There's > a single feedline coming inside from that tower-mounted switchbox. Each > piece of radio gear and the computer inside is bonded by 1" braid going to a > copper bus. LAN and voice line comms are not, however the connection from > the pole is fiber, not copper so that's not likely a problem. Agreed. > The copper bus > inside is bonded to a ground rod outside the shack, which in turn is bonded > to the tower ground system. > > The deficiency is that the copper bus is not grounded to the same point as > the tower, since the tower is about 50 feet away from the shack. This distance is borderline for bonding to the house. > I guess I > could run a 50 or 60' run of 2" strapping from the desk, through the floor, > across the crawlspace, and out the conduit to the tower, but I suspect that > might be more a hindrance than a help, quite honestly. Agreed. My shack is in what used to be a "mother-in-law" apartment of a detached garage. I have a rod where power enters that building (fed from the house), a half-perimeter #6 running around the building to the shack, where there are five driven rods, all exposed to rainfall, and three rods along that perimeter ground. The coax entry panels (added a second one when the first filled up) on the wall of the shack are bonded down to the rods and up to the ground bus for the equipment. They're also bonded to steel conduit that runs back to the entry panel. 73, Jim K9YC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
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Pete,
I had a similar problemon lower end of 80 meters. Fix for me was to ground outer jacket of all antenna cables where they enter the house. This eliminated common mode current coming into the shack on a second coax. Check your RX antenna cable, which does not go through the RCS-12. Dave wo2x Sent from my iPad > On Mar 11, 2019, at 6:13 PM, Jim Brown <[hidden email]> wrote: > >> On 3/11/2019 1:40 PM, Peter Dougherty wrote: >> I've got my bonding about as good as I can get it for the moment, although >> I'm probably going to do some improvements this year. The lightning >> arrestors are built in to the RCS-12 antenna switchbox (RCS-12L with the gas >> discharge tubes), and everything's bonded at the base of the tower. > The function of GDTs is to offer some protection of equipment in the event of a strike. To do that, they must be close to the equipment, not at the tower. Lightning can induce a lot of current on the coax between the tower and the shack. I suggest that you add arrestors (including that vertical you use for RX) where all of your coax enters the shack, bond them to your rod(s), and to the shack bonding. That's probably the missing bonding that I suspected! Also, what about bonding to the power entry panel? >> There's >> a single feedline coming inside from that tower-mounted switchbox. Each >> piece of radio gear and the computer inside is bonded by 1" braid going to a >> copper bus. LAN and voice line comms are not, however the connection from >> the pole is fiber, not copper so that's not likely a problem. > Agreed. >> The copper bus >> inside is bonded to a ground rod outside the shack, which in turn is bonded >> to the tower ground system. >> >> The deficiency is that the copper bus is not grounded to the same point as >> the tower, since the tower is about 50 feet away from the shack. > This distance is borderline for bonding to the house. >> I guess I >> could run a 50 or 60' run of 2" strapping from the desk, through the floor, >> across the crawlspace, and out the conduit to the tower, but I suspect that >> might be more a hindrance than a help, quite honestly. > > Agreed. > > My shack is in what used to be a "mother-in-law" apartment of a detached garage. I have a rod where power enters that building (fed from the house), a half-perimeter #6 running around the building to the shack, where there are five driven rods, all exposed to rainfall, and three rods along that perimeter ground. The coax entry panels (added a second one when the first filled up) on the wall of the shack are bonded down to the rods and up to the ground bus for the equipment. They're also bonded to steel conduit that runs back to the entry panel. > > 73, Jim K9YC > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html |
Re: 80m KPA1500 High reflected power problems **SOLVED!**
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This summer I intend to get an entry panel from KF7P, along with a ton of
arrestors inside for everything. The real difficult part will be getting all the cables that now enter the house at base of the tower and across the crawl space to instead run under the deck. I'm to tall, too fat, and too creaky to slither under there over rocks and gravel to run a half-dozen or more cables. I should consider hiring someone to attach some 4" conduit with sweeps under there. It would make the problem go away quickly. - pjd -----Original Message----- From: [hidden email] <[hidden email]> On Behalf Of Dave Sent: Monday, March 11, 2019 8:52 PM Cc: Reflector Elecraft <[hidden email]> Subject: Re: [Elecraft] 80m KPA1500 High reflected power problems **SOLVED!** Pete, I had a similar problemon lower end of 80 meters. Fix for me was to ground outer jacket of all antenna cables where they enter the house. This eliminated common mode current coming into the shack on a second coax. Check your RX antenna cable, which does not go through the RCS-12. Dave wo2x Sent from my iPad > On Mar 11, 2019, at 6:13 PM, Jim Brown <[hidden email]> wrote: > >> On 3/11/2019 1:40 PM, Peter Dougherty wrote: >> I've got my bonding about as good as I can get it for the moment, >> although I'm probably going to do some improvements this year. The >> lightning arrestors are built in to the RCS-12 antenna switchbox >> (RCS-12L with the gas discharge tubes), and everything's bonded at the base of the tower. > The function of GDTs is to offer some protection of equipment in the event of a strike. To do that, they must be close to the equipment, not at the tower. Lightning can induce a lot of current on the coax between the tower and the shack. I suggest that you add arrestors (including that vertical you use for RX) where all of your coax enters the shack, bond them to your rod(s), and to the shack bonding. That's probably the missing bonding that I suspected! Also, what about bonding to the power entry panel? >> There's >> a single feedline coming inside from that tower-mounted switchbox. >> Each piece of radio gear and the computer inside is bonded by 1" >> braid going to a copper bus. LAN and voice line comms are not, >> however the connection from the pole is fiber, not copper so that's not likely a problem. > Agreed. >> The copper bus >> inside is bonded to a ground rod outside the shack, which in turn is >> bonded to the tower ground system. >> >> The deficiency is that the copper bus is not grounded to the same >> point as the tower, since the tower is about 50 feet away from the shack. > This distance is borderline for bonding to the house. >> I guess I >> could run a 50 or 60' run of 2" strapping from the desk, through the >> floor, across the crawlspace, and out the conduit to the tower, but I >> suspect that might be more a hindrance than a help, quite honestly. > > Agreed. > > My shack is in what used to be a "mother-in-law" apartment of a detached a half-perimeter #6 running around the building to the shack, where there are five driven rods, all exposed to rainfall, and three rods along that perimeter ground. The coax entry panels (added a second one when the first filled up) on the wall of the shack are bonded down to the rods and up to the ground bus for the equipment. They're also bonded to steel conduit that runs back to the entry panel. > > 73, Jim K9YC > > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[hidden email] > > This list hosted by: http://www.qsl.net Please help support this email > list: http://www.qsl.net/donate.html Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[hidden email] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Lovin' my K3S (S/N 10023)
73, Peter W2IRT |
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