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#1
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Grounding question
I plan to build a random wire antenna in my backyard with an RG8X
feedline. I want to ground the feedline just before it enters the house. Can I connect the coax to a SO-239 to SO-239 adapter (I think it's called a PL-258), then attach the adapter directly to a ground rod using a hose clamp? Or, should I buy a lightning arrestor (e.g., Zap Trapper) and attach that to ground rod just outside the house? Thanks. |
#2
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Grounding question
wrote:
I plan to build a random wire antenna in my backyard with an RG8X feedline. I want to ground the feedline just before it enters the house. Can I connect the coax to a SO-239 to SO-239 adapter (I think it's called a PL-258), then attach the adapter directly to a ground rod using a hose clamp? Or, should I buy a lightning arrestor (e.g., Zap Trapper) and attach that to ground rod just outside the house? Thanks. Use RG6. For HF receive it'll work just as well and you can use Type F accessories. http://www.satellitedish.com/cata0102.htm Be sure to use an SWL Balun at the feedpoint. http://www.buxcomm.com/catalog/index...index&cPath=11 Or roll your own http://palomar-engineers.com/9_1_Bal...balun_kit.html |
#3
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Grounding question
On Jan 19, 6:19*am, wrote:
I plan to build a random wire antenna in my backyard with an RG8X feedline. I want to ground the feedline just before it enters the house. Can I connect the coax to a SO-239 to SO-239 adapter (I think it's called a PL-258), then attach the adapter directly to a ground rod using a hose clamp? Or, should I buy a lightning arrestor (e.g., Zap Trapper) and attach that to ground rod just outside the house? Thanks. 7600d, For simply Grounding the Outer-Shield of the RG8X Coax Cable that will work. |
#4
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Grounding question
RHF wrote:
For simply Grounding the Outer-Shield of the RG8X Coax Cable that will work. However, it may not be legal (i.e. according to "code") and therefore would invalidate your home owner's insurance, etc. AFAIK in the US, all grounds must be bonded together. Geoff. -- Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM |
#5
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Grounding question
However, it may not be legal (i.e. according to "code") and therefore would invalidate your home owner's insurance, etc. AFAIK in the US, all grounds must be bonded together. Geoff. Thanks everyone for the helpful tips. Geoff, when you say that the grounds must be bonded, do you mean that the ground rod I install just outside my shack has to be connected to my home's electrical grounding system? Would I simply run a wire between the two grounds? The problem with this is that it's quite a long run to the electrical ground, and I'm guessing that the connecting ground wire would pick up a lot of noise. Is this a justified concern? Thanks |
#6
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Grounding question
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#7
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Grounding question
On Jan 19, 10:05*pm, Telamon
wrote: In article , wrote: I plan to build a random wire antenna in my backyard with an RG8X feedline. I want to ground the feedline just before it enters the house. Can I connect the coax to a SO-239 to SO-239 adapter (I think it's called a PL-258), then attach the adapter directly to a ground rod using a hose clamp? Or, should I buy a lightning arrestor (e.g., Zap Trapper) and attach that to ground rod just outside the house? Thanks. Zap Tapper is OK to use. There are others on this page you can use. http://www.universal-radio.com/catalog/protect.html -- Telamon Ventura, California Thanks for the links Telamon and RHF. Here is my plan: random wire -- 9:1 xfmr & ground -- RG8X -- lightning arrester & ground -- RG8X (enters house) -- Rx Actually, the random wire/xmfr part is the Par Electronics EF-SWL - should be arriving in the mail next week. Some questions: 1. Does the grounded lightning arrestor cause the coax shield to be grounded? In other words, in addition to being part of a lightning ground system, does the arrestor help reduce "common mode" noise? I'm trying to follow the RF ground principles outlined by John Doty in his article "Grounding is key to good reception". Here is the relevant quote: "The ground stake near the house provides a place for the common mode noise current to go, far from the antenna where it cannot couple significantly." If the lightning arrestor doesn't ground the coax shield (I'm guessing it does, since the coax shield touches the arrestor which is connected to a ground rod), should I buy a 50ohm ground block and attach my feedline to it just prior to the arrestor? The technical notes on the ICE Radio Products website suggest that you need a ground block and an arrestor, but maybe I'm confused. 2. I've read that, during a lightning storm, you should disconnect the coax from the back of the receiver and disconnect the power cord. However, I've also read that letting the disconnected feedline simply dangle in your radio room during a storm is not a good idea. Any ideas on how to safely disconnect the feedline from the receiver? Geoff, your post regarding "bonding" and following my jurisdiction's electrical code is a good one. I will be looking into it asap. Thanks. |
#8
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Grounding question
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#9
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Grounding question
On Jan 21, 11:33*pm, Telamon
wrote: In article , wrote: On Jan 19, 10:05*pm, Telamon wrote: In article , wrote: I plan to build a random wire antenna in my backyard with an RG8X feedline. I want to ground the feedline just before it enters the house. Can I connect the coax to a SO-239 to SO-239 adapter (I think it's called a PL-258), then attach the adapter directly to a ground rod using a hose clamp? Or, should I buy a lightning arrestor (e.g., Zap Trapper) and attach that to ground rod just outside the house? Thanks. Zap Tapper is OK to use. There are others on this page you can use. http://www.universal-radio.com/catalog/protect.html -- Telamon Ventura, California Thanks for the links Telamon and RHF. Here is my plan: random wire -- 9:1 xfmr & ground -- RG8X -- lightning arrester & ground -- RG8X (enters house) -- Rx Actually, the random wire/xmfr part is the Par Electronics EF-SWL - should be arriving in the mail next week. Some questions: 1. *Does the grounded lightning arrestor cause the coax shield to be grounded? *In other words, in addition to being part of a lightning ground system, does the arrestor help reduce "common mode" noise? Technically no but practically yes. Technically the arrestor is not a common mode reduction device but practically common mode currents exist on the coax from the radio then mains connection along with RFI it may have picked up from the environment. The arrestor does ground the outer coax braid but normally it does not affect the center conductor unless a voltage rise causes the internal tube element to briefly conduct so in effect it is a differential device. I'm trying to follow the RF ground principles outlined by John Doty in his article "Grounding is key to good reception". Here is the relevant quote: "The ground stake near the house provides a place for the common mode noise current to go, far from the antenna where it cannot couple significantly." If the lightning arrestor doesn't ground the coax shield (I'm guessing it does, since the coax shield touches the arrestor which is connected to a ground rod), should I buy a 50ohm ground block and attach my feedline to it just prior to the arrestor? A ground block just grounds the coax shield. An arrestor also grounds the shield but also has a device inside such as a 2 element tube that conducts under high voltage conditions to the center conductor. The technical notes on the ICE Radio Products website suggest that you need a ground block and an arrestor, but maybe I'm confused. For the arrestor to be effective it must be grounded so the high voltage and current created by the lightening has a place to go besides your radio. 2. *I've read that, during a lightning storm, you should disconnect the coax from the back of the receiver and disconnect the power cord. However, I've also read that letting the disconnected feedline simply dangle in your radio room during a storm is not a good idea. *Any ideas on how to safely disconnect the feedline from the receiver? Disconnect it from the radio, put a cover on the end and put it outside a widow. Geoff, your post regarding "bonding" and following my jurisdiction's electrical code is a good one. *I will be looking into it asap. Thanks. Bonding means to directly as possible connect all grounds together. This is done so all the appliances and things like radios are raised to a common ground potential during a strike. This is just one way to protect anything plugged into the mains supply and you during a nearby lightening strike. -- Telamon Ventura, California- Hide quoted text - - Show quoted text - Thank you very much Telamon!! |
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