USB mouse and RF

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kd2goe

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I have been working on my radio room for a few weeks. Got my radio all hooked up and my computer hooked up and I'm having a problem I figured I'd run into..
When ever i key my radio over 30 watts my USB mouse dies then i have to unplug it and replug it in. i have added ferrite cores to the USB wire and ground in my radio directly to water pipe.. i feal it is just becus it is a cheep USB Mouse. Any recommendations on a mouse??

 
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jonwienke

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It's probably due to RF feeding down your coax and overloading the circuits on the mouse. You need to put ferrite chokes on the coax where it leaves the antenna, to eliminate the problem at the source. Otherwise you could fry your mouse and/or your computer if you turn up the RF power.
 

kd2goe

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It's probably due to RF feeding down your coax and overloading the circuits on the mouse. You need to put ferrite chokes on the coax where it leaves the antenna, to eliminate the problem at the source. Otherwise you could fry your mouse and/or your computer if you turn up the RF power.
Did that even have a loop at the feed point of the antenna
 

jonwienke

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How many turns, and what diameter?
 

N0IU

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Here's my set up:



The mouse I currently use is a Logitech M325 that I think was around $15 at Wal-Mart. As you can see, the mouse (the one on the mouse pad) is less than a foot away from the radio and the computer itself is even closer and I don't have any issues with the mouse or anything with the computer.

But here's the part that bothers me:

...and ground in my radio directly to water pipe.
You should disconnect your ground from the water pipe. When you think about all the copper in your house, your entire plumbing system could be acting like one huge antenna! Ideally, you should ground your radio to an 8' copper ground rod outside your house as close as possible to the radio.
 

jonwienke

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4" 10 turns
That should be fine for VHF and higher, but for HF, you may need more turns. The number of turns needed to block RF is directly proportional to wavelength.
 

AK9R

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It's always a good idea to eliminate the stray RF in the shack at its source. That said, the mouse cable is acting as an antenna and is picking up the RF. I have the same problem with the USB cable between my radio and computer even though that cable has ferrites at both ends.

Another possible solution is to get rid of the antenna on the mouse by switching to a wireless mouse.
 

jim202

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Use of copper pip in the house as a ground may or may not work. I say this because most water feeds to buildings these days are using some form of PVC pipe. You really need to look at where the water comes into your house and see just what type of pipe is coming into the house. Unless you have a really old house, like built in the 50's to the early 70's, my bet is you will find plastic coming from the water company.

Your best bet is to install your own ground system. Hopefully your point of going outside the house is fairly near the electrical meter. You should find a ground rod under the meter with a solid copper wire coming from the meter and going to the ground rod. This is required by the NEC.

Now with that said, let me go back to installing your own ground system. Yes I said system. The use of a single ground rod probably won't provide you with an ideal ground with a resistance of less than 5 Ohms. Generally it takes installing 2 or more ground rods and connecting them together.

Make sure you space the rods out so that they are no closer than twice their length. In other words, if you use 8 foot ground rods, the distance between them wants to be 16 feet. This is due to the cone of influence around each ground rod. If you space them closer, the cones will overlap and you will not gain the full effect of the ground resistance each rod will provide.

The ideal connection between the rods and the solid number 2, tinned wire would be an exothermic weld at each ground rod. The tinned copper wire reduces corrosion much better than just plain old bare copper. Unless your in the electrical service business, you won't have access to this process. Another way would be to use a mechanical compression connection. Again, you would need the crimping tool and the compression clips. So the last, least desirable way would be to just use the bronze grounding sleeves you can get from your local hardware store or a place like Lowe's or Home depot.

Going back to the ground rod at the electrical meter that I mentioned at the start. The NEC (National Electrical Code) provides an exception to a radio facility or telecommunications facility to connect the site grounding system to the electrical service ground. This places them at both the same potential and reduces damage from lightning strikes and surges.

Make sure your antenna systems have surge protection on them that is connected to your ground system. It is also wise to install surge protection on you electrical feeds. Many places put a master surge protection device right at the electrical breaker panel. The shorter the wires are between them, the better. Use no metal sleeves to connect the boxes as these act as a choke to surges. You want the surge protector to do it's job. Then make sure you have a low resistance ground going to the surge protector. Again don't use metal conduit to run the ground wire through.

Hope this gives you something to think about in grounding your equipment.
 

kd2goe

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Use of copper pip in the house as a ground may or may not work. I say this because most water feeds to buildings these days are using some form of PVC pipe. You really need to look at where the water comes into your house and see just what type of pipe is coming into the house. Unless you have a really old house, like built in the 50's to the early 70's, my bet is you will find plastic coming from the water company.

Your best bet is to install your own ground system. Hopefully your point of going outside the house is fairly near the electrical meter. You should find a ground rod under the meter with a solid copper wire coming from the meter and going to the ground rod. This is required by the NEC.

Now with that said, let me go back to installing your own ground system. Yes I said system. The use of a single ground rod probably won't provide you with an ideal ground with a resistance of less than 5 Ohms. Generally it takes installing 2 or more ground rods and connecting them together.

Make sure you space the rods out so that they are no closer than twice their length. In other words, if you use 8 foot ground rods, the distance between them wants to be 16 feet. This is due to the cone of influence around each ground rod. If you space them closer, the cones will overlap and you will not gain the full effect of the ground resistance each rod will provide.

The ideal connection between the rods and the solid number 2, tinned wire would be an exothermic weld at each ground rod. The tinned copper wire reduces corrosion much better than just plain old bare copper. Unless your in the electrical service business, you won't have access to this process. Another way would be to use a mechanical compression connection. Again, you would need the crimping tool and the compression clips. So the last, least desirable way would be to just use the bronze grounding sleeves you can get from your local hardware store or a place like Lowe's or Home depot.

Going back to the ground rod at the electrical meter that I mentioned at the start. The NEC (National Electrical Code) provides an exception to a radio facility or telecommunications facility to connect the site grounding system to the electrical service ground. This places them at both the same potential and reduces damage from lightning strikes and surges.

Make sure your antenna systems have surge protection on them that is connected to your ground system. It is also wise to install surge protection on you electrical feeds. Many places put a master surge protection device right at the electrical breaker panel. The shorter the wires are between them, the better. Use no metal sleeves to connect the boxes as these act as a choke to surges. You want the surge protector to do it's job. Then make sure you have a low resistance ground going to the surge protector. Again don't use metal conduit to run the ground wire through.

Hope this gives you something to think about in grounding your equipment.
I shod have been more clear

I have a 10' rod grounding at my antenna from that a 10awg copper wire running in to my basement to a binding post/clamp that links my radio to the water pipe the 3/4 water pipe runs to the meter. There is a post/clamp on the 3/4 pipe to the house electrical panel and to a secant 10' grounding rod.

I am planning to add 1 more 10' grounding rod at the antenna
 

N0IU

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Personally, I would very strongly suggest that you remove all connections from any part of your station to any part of your water system.

Of course you have some sort of power supply for your radio and I assume it most certainly has a 3-prong grounded plug to your wall outlet, but other than that, your system should not be tied into your home's electrical system.

There are two types of "ground". One is the electrical ground for the safety of your equipment and there is the RF ground that could be part of your antenna systems and it sounds like you are trying to tie all of these together. They are two completely separate things.
 

kd2goe

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Personally, I would very strongly suggest that you remove all connections from any part of your station to any part of your water system.

Of course you have some sort of power supply for your radio and I assume it most certainly has a 3-prong grounded plug to your wall outlet, but other than that, your system should not be tied into your home's electrical system.

There are two types of "ground". One is the electrical ground for the safety of your equipment and there is the RF ground that could be part of your antenna systems and it sounds like you are trying to tie all of these together. They are two completely separate things.
why?

as some point in the system it will be connected to it...?
 

majoco

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The auto-tuner in the TS2K may be masking a high VSWR - meaning that you have RF back in the shack. Do you get the same effect on all frequencies?
 

kd2goe

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Start here: Antennas, Feedlines, Towers & Rotors

There are 3 "stickies" at the top that cover grounding in great detail.
what sucks is I hear 3 different ways to do it and it is hard to know what is right...

any way as for code you need to have a ground strap in your water pipe from the mains.. ill read the links and apply what is recommended

this is how I have it set up
http://www.w8ji.com/images/Grounding/Houseground-best.gif

from this web page
House ground layouts
 
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K4PIH

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Springfield, Virginia
Let me add one more way to address the problem, based on my personal experience. Make sure that your antenna coax and the mouse cable (keyboard too) do not run close together or cross one another. Abour 2 years ago I had a scan line that would run from the top of my LCD monitor to the bottom and repeat. I thought the monitor was bad, but it was the monitor cable and the power cable to the computer crossed at a 90 degree and the ac ripple was getting on to the monitor data cable. Seperated them and problem vanished. Could be that your COAX is close to the mouse cable or port and the RF above a certain level gets in. Make sure they are not parallel, close, or cross. May not be it but it's worth a try.
 
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