Re: Topband: earth tester
What do you want to measure? These testers, as well as the fall of potential method, measure the impedance to earth at dc and low audio frequencies. It's important to remember that a connection to earth is for lightning protection, and does not make a TX antenna work better. If you want to measure your soil conditions, N6LF shows a method on his website. It uses a driven rod that passes through an opening in a wire screen. Z between the rod and the screen is measured using a vector impedance analyzer, first before the rod is driven, and again after being driven to its full length, and soil parameters are computed from the two measurements. I've thought about doing this, but never got around to it. This measurement yields the data on the soil conditions that affect the performance of vertical antennas. 73, Jim K9YC On Wed,4/22/2015 6:00 AM, Paul Christensen wrote: Do you use a earth tester? Which brand do you know is very good and accurate to consider? Jorge, If you can, try and find a clamp-on earth tester rather than the type that relies on the fall-of-potential method with electrodes. There are several good clamp-on units by Megger, Fluke and AEMC. I recently acquired an AEMC model 3711. It wasn't supplied with a calibration loop, but I found one from Fluke that quickly checks calibration at 100, 50, 12.5, and 0.5 ohms. You'll want that calibration loop to validate the accuracy of the clamp tester, especially if you use an off-brand model from Asia. N4CC and I recently installed a large grounding field, with some ground rods driven down to a depth of 24 ft. The clamp-on device was useful for quick validation. Had we used a unit with electrodes, it would have taken us much longer to perform our tests. By the way, in sandy/clay type soil here in north FL, we found that connecting 8 ft. rods end-to-end to form a 24 ft rod substantially lowered earth resistance by a factor of 10x. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: earth tester
Thanks information Paul. Many believe all the conductivity is in the first three or four feet from the surface. There are many variations around the globe. Surface sand, desert, and California parched soil can be close to an insulator. Other may have conductive minerals at some depth. I like long grounds. Impact drivers/drills can be an assistance getting to the depth wanted. 73 Bruce-K1FZ www.qsl.net/k1fz/beverage_antenna.html On Wed, 22 Apr 2015 09:00:02 -0400, Paul Christensen wrote: Do you use a earth tester? Which brand do you know is very good and accurate to consider? Jorge, If you can, try and find a clamp-on earth tester rather than the type that relies on the fall-of-potential method with electrodes. There are several good clamp-on units by Megger, Fluke and AEMC. I recently acquired an AEMC model 3711. It wasn't supplied with a calibration loop, but I found one from Fluke that quickly checks calibration at 100, 50, 12.5, and 0.5 ohms. You'll want that calibration loop to validate the accuracy of the clamp tester, especially if you use an off-brand model from Asia. N4CC and I recently installed a large grounding field, with some ground rods driven down to a depth of 24 ft. The clamp-on device was useful for quick validation. Had we used a unit with electrodes, it would have taken us much longer to perform our tests. By the way, in sandy/clay type soil here in north FL, we found that connecting 8 ft. rods end-to-end to form a 24 ft rod substantially lowered earth resistance by a factor of 10x. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: earth tester
Hello Do you use a earth tester? Which brand do you know is very good and accurate to consider? Thanks! Jorge CX6VM/CW5W --- El software de antivirus Avast ha analizado este correo electrónico en busca de virus. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: earth tester
Perhaps a few words on how you joined the rods would be useful here. Regards,Jeff W6JK On Wednesday, April 22, 2015 1:00 PM, Paul Christensen w...@arrl.net wrote: Do you use a earth tester? Which brand do you know is very good and accurate to consider? Jorge, If you can, try and find a clamp-on earth tester rather than the type that relies on the fall-of-potential method with electrodes. There are several good clamp-on units by Megger, Fluke and AEMC. I recently acquired an AEMC model 3711. It wasn't supplied with a calibration loop, but I found one from Fluke that quickly checks calibration at 100, 50, 12.5, and 0.5 ohms. You'll want that calibration loop to validate the accuracy of the clamp tester, especially if you use an off-brand model from Asia. N4CC and I recently installed a large grounding field, with some ground rods driven down to a depth of 24 ft. The clamp-on device was useful for quick validation. Had we used a unit with electrodes, it would have taken us much longer to perform our tests. By the way, in sandy/clay type soil here in north FL, we found that connecting 8 ft. rods end-to-end to form a 24 ft rod substantially lowered earth resistance by a factor of 10x. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: earth tester
Do you use a earth tester? Which brand do you know is very good and accurate to consider? Jorge, If you can, try and find a clamp-on earth tester rather than the type that relies on the fall-of-potential method with electrodes. There are several good clamp-on units by Megger, Fluke and AEMC. I recently acquired an AEMC model 3711. It wasn't supplied with a calibration loop, but I found one from Fluke that quickly checks calibration at 100, 50, 12.5, and 0.5 ohms. You'll want that calibration loop to validate the accuracy of the clamp tester, especially if you use an off-brand model from Asia. N4CC and I recently installed a large grounding field, with some ground rods driven down to a depth of 24 ft. The clamp-on device was useful for quick validation. Had we used a unit with electrodes, it would have taken us much longer to perform our tests. By the way, in sandy/clay type soil here in north FL, we found that connecting 8 ft. rods end-to-end to form a 24 ft rod substantially lowered earth resistance by a factor of 10x. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: VK6DXI
What a so sad news... He'd sent me a sound file recorded myself on 2013. I have no words to say but... RIP Mirek. -- 73, Sugi JI3KDH _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: earth tester
Thanks Paul Will search about this 73, Jorge -Mensaje original- De: Topband [mailto:topband-boun...@contesting.com] En nombre de Paul Christensen Enviado el: miércoles, 22 de abril de 2015 10:00 a.m. Para: topband Asunto: Re: Topband: earth tester Do you use a earth tester? Which brand do you know is very good and accurate to consider? Jorge, If you can, try and find a clamp-on earth tester rather than the type that relies on the fall-of-potential method with electrodes. There are several good clamp-on units by Megger, Fluke and AEMC. I recently acquired an AEMC model 3711. It wasn't supplied with a calibration loop, but I found one from Fluke that quickly checks calibration at 100, 50, 12.5, and 0.5 ohms. You'll want that calibration loop to validate the accuracy of the clamp tester, especially if you use an off-brand model from Asia. N4CC and I recently installed a large grounding field, with some ground rods driven down to a depth of 24 ft. The clamp-on device was useful for quick validation. Had we used a unit with electrodes, it would have taken us much longer to perform our tests. By the way, in sandy/clay type soil here in north FL, we found that connecting 8 ft. rods end-to-end to form a 24 ft rod substantially lowered earth resistance by a factor of 10x. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband --- El software de antivirus Avast ha analizado este correo electrónico en busca de virus. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: earth tester
“Perhaps a few words on how you joined the rods would be useful here.” We used TB/Blackburn 60CNT2 non-threaded couplers to join the ground rods. A compression fit is used to join the rods. The rods and couplers were obtained from our rural electric company.The utility also supplied a head driver that fits inside a ground rod bit for use with a rotary impact drill. http://www.tnb.com/ps/fulltilt/index.cgi?part=60CNT2 Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: earth tester
Thanks Jim I will look at N6LF website, I want to measure my soil conditions 73, Jorge -Mensaje original- De: Topband [mailto:topband-boun...@contesting.com] En nombre de Jim Brown Enviado el: miércoles, 22 de abril de 2015 01:48 p.m. Para: topband@contesting.com Asunto: Re: Topband: earth tester What do you want to measure? These testers, as well as the fall of potential method, measure the impedance to earth at dc and low audio frequencies. It's important to remember that a connection to earth is for lightning protection, and does not make a TX antenna work better. If you want to measure your soil conditions, N6LF shows a method on his website. It uses a driven rod that passes through an opening in a wire screen. Z between the rod and the screen is measured using a vector impedance analyzer, first before the rod is driven, and again after being driven to its full length, and soil parameters are computed from the two measurements. I've thought about doing this, but never got around to it. This measurement yields the data on the soil conditions that affect the performance of vertical antennas. 73, Jim K9YC On Wed,4/22/2015 6:00 AM, Paul Christensen wrote: Do you use a earth tester? Which brand do you know is very good and accurate to consider? Jorge, If you can, try and find a clamp-on earth tester rather than the type that relies on the fall-of-potential method with electrodes. There are several good clamp-on units by Megger, Fluke and AEMC. I recently acquired an AEMC model 3711. It wasn't supplied with a calibration loop, but I found one from Fluke that quickly checks calibration at 100, 50, 12.5, and 0.5 ohms. You'll want that calibration loop to validate the accuracy of the clamp tester, especially if you use an off-brand model from Asia. N4CC and I recently installed a large grounding field, with some ground rods driven down to a depth of 24 ft. The clamp-on device was useful for quick validation. Had we used a unit with electrodes, it would have taken us much longer to perform our tests. By the way, in sandy/clay type soil here in north FL, we found that connecting 8 ft. rods end-to-end to form a 24 ft rod substantially lowered earth resistance by a factor of 10x. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband --- El software de antivirus Avast ha analizado este correo electrónico en busca de virus. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: earth tester
Jim, And after measuring it, I don't believe anyone will do anything about it. The PolyPhaser manual has some good info on lightning protection. 73 de Price W0RI On Wednesday, April 22, 2015 11:47 AM, Jim Brown j...@audiosystemsgroup.com wrote: What do you want to measure? These testers, as well as the fall of potential method, measure the impedance to earth at dc and low audio frequencies. It's important to remember that a connection to earth is for lightning protection, and does not make a TX antenna work better. If you want to measure your soil conditions, N6LF shows a method on his website. It uses a driven rod that passes through an opening in a wire screen. Z between the rod and the screen is measured using a vector impedance analyzer, first before the rod is driven, and again after being driven to its full length, and soil parameters are computed from the two measurements. I've thought about doing this, but never got around to it. This measurement yields the data on the soil conditions that affect the performance of vertical antennas. 73, Jim K9YC On Wed,4/22/2015 6:00 AM, Paul Christensen wrote: Do you use a earth tester? Which brand do you know is very good and accurate to consider? Jorge, If you can, try and find a clamp-on earth tester rather than the type that relies on the fall-of-potential method with electrodes. There are several good clamp-on units by Megger, Fluke and AEMC. I recently acquired an AEMC model 3711. It wasn't supplied with a calibration loop, but I found one from Fluke that quickly checks calibration at 100, 50, 12.5, and 0.5 ohms. You'll want that calibration loop to validate the accuracy of the clamp tester, especially if you use an off-brand model from Asia. N4CC and I recently installed a large grounding field, with some ground rods driven down to a depth of 24 ft. The clamp-on device was useful for quick validation. Had we used a unit with electrodes, it would have taken us much longer to perform our tests. By the way, in sandy/clay type soil here in north FL, we found that connecting 8 ft. rods end-to-end to form a 24 ft rod substantially lowered earth resistance by a factor of 10x. Paul, W9AC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: 26th Annual Dayton TopBand Dinner
The annual Dayton Topband dinner will be held Friday (May 15) night during Dayton Hamvention at the Crowne Plaza. Great place to meet Topband ops - it is a super dinner event. Our special guest speaker this year is Bob, K4UEE presenting Topband experiences from Navassa Island, K1N. All the details are here: http://topbanddinner.com 73, Tim K3LR Topband Dinner Host _ Topband Reflector Archives - http://www.contesting.com/_topband
