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#11
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Dan wrote:
- But Counterweight sounds better. Depends if your prefer weight to poise. 'Weight' is certainly manlier... mike |
#12
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Lucky wrote:
Hi guys! I live on the 23rd floor of a building so I can't use the earth directly for the ground. The options in my "radio room" are the ground from the electrical sockets and that's about it. I've heard I can roll out 10ft of tin foil on the floor as a ground {that's out}, or, use the window frames as a good ground. As far as I can tell, the window frame looks to be aluminum or some sort of alloy. Have any of you heard of using a window frame as a ground? I think I read it in this NG that someone recommended it and was using it for his ground. I've been using the ground from an electrical outlet. But being that so many people live in the building that use appliances and other plugged in items all day and night, I sometimes get what seems like bad feedback affecting the receiver. So what do you think of the window frame for the ground then? I welcome any other options I can use in a room very far from a direct earth ground. The bathroom pipes are all the way across the room separated by a wall. Not easy to get to. Thanks for any help Lucky hi, at that height the metal window frame makes a good antenna, but not a ground. use the electical outlet ground for a ground potential |
#13
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m II wrote:
Dan wrote: - But Counterweight sounds better. Depends if your prefer weight to poise. 'Weight' is certainly manlier... mike RF is weightless! ;-) -- Former professional electron wrangler. Michael A. Terrell Central Florida |
#14
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Again what about built up static?
Static is rf just like any other signal...When you listen to lightning crashes, you are listening to lightning "radio". Now, if you actually have static build up on the antenna, IE from dry weather, etc, you can always add a resister, etc to bleed it off. But hear in TX, I never bother. It's not an issue here. Where does it go then? Where does any other signal go? I usually switch between my 2 antennas to see what brings the frequency in better, the random wire or the dipole. So I don't stay with one fixed antenna all the time. A ground would still not be needed then? No. So I take it most of you not transmitting are not grounded? Well, many do I'm sure, but I don't. I don't use an rf ground to my shack at all. I don't need one. You have basically three types of grounds. The safety ground, the rf ground for the antenna, and the lightning protection ground. Many times the last two are combined. Your power line ground is the "safety ground". You only need a safety ground in the shack, if your radio, etc requires one. If it does require one, it usually will have a third grounding pin on the plug. Many radios do not need a safety ground. Actually these days, *most* radios do not require a safety ground. IE: look at a TV...Do you see a ground pin on the plug? Thats what I thought.... Then you have the RF ground for the antenna. Normally, it should be at or under the antenna, *if* the antenna requires it to complete the antenna. IE: vertical monopoles, etc... If you use a random wire, and ground the shield, it's best to do that outside at the base of the antenna. This assumes a coax feed... On the 24th floor, you will never be able to get a decent RF ground that won't act as an antenna, so thats really your only option. Otherwise, if just a random wire to the radio, I wouldn't bother. If you use a dipole, or other antenna that is complete in itself, there is absolutely no need for an rf ground at the antenna, or the radio. Nada, none, zilch. This is the way I operate. All my antennas are complete, or have rf grounds under them. The lightning ground is purely to direct the strike to ground, and maybe protect the radio, if you want to go that far. There are plenty of threads covering that hornets nest, so you can research that on your own. The lightning ground, I *do* use...But...It's all outside...Has nothing to do with my shack. Grounding is pretty complicated, per the reason/s, and is probably one of the most "wives tales" loaded topics you can find. Inside a 24 th floor highrise, you don't need to worry about static buildup...If you did, probably half the electronics stuff in the place would be toast by now...As far as listening, and static noise, there may well be nothing you can do about it, other than using a coax fed antenna that is outside, and away from the noise source, assuming that source is inside with you. MK |
#15
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ryan wiehle wrote in message ... Lucky wrote: Hi guys! I live on the 23rd floor of a building so I can't use the earth directly for the ground. The options in my "radio room" are the ground from the electrical sockets and that's about it. I've heard I can roll out 10ft of tin foil on the floor as a ground {that's out}, or, use the window frames as a good ground. As far as I can tell, the window frame looks to be aluminum or some sort of alloy. Have any of you heard of using a window frame as a ground? I think I read it in this NG that someone recommended it and was using it for his ground. I've been using the ground from an electrical outlet. But being that so many people live in the building that use appliances and other plugged in items all day and night, I sometimes get what seems like bad feedback affecting the receiver. So what do you think of the window frame for the ground then? I welcome any other options I can use in a room very far from a direct earth ground. The bathroom pipes are all the way across the room separated by a wall. Not easy to get to. Thanks for any help Lucky hi, at that height the metal window frame makes a good antenna, but not a ground. use the electical outlet ground for a ground potential Hi Ryan. You hit that right on the head. One of the other posters stated the window frame would make an antenna NOT a ground. So I decided to try it as one. I connected the wire to the antenna terminal on the R75 from the ground. I couldn't believe it! What a good antenna it made. Most of the time the S-Meter was peaking higher with it then the dipole. Even though the noise floor was increased in some cases, the signal was much more loud, clear and audible. In a couple cases I needed to turn on the pre amp to hear the signal with the dipole but with the window frame antenna it didn't need it at all! Yes I realize that certain size dipoles will limit some frequencies it's not perfected for, but this setup brought in better signals across the board most of the time. Of course there was few frequencies it just was terrible at. Now if you use the R75's options, you can remove most of that extra noise. I'd rather have a audible signal that I can listen to with some noise then one so weak you can't interpret what is being said. So I would say this ground experimentation exposed a pretty decent optional antenna! Being up so high makes that frame a real signal magnet. What a great find for someone who can't put up outside antennas or perhaps would get better results then what they are using now. So what kind of antenna do you think this rectangle aluminum frame makes? What could it be compared to? As for the electrical ground, I realize it's more of a "safety" ground then a RF ground as one poster pointed out. So by using the electrical sockets ground, what am I actually grounding? The radio itself, the antennas or both? I'm figuring just the radio from lightning strikes or static? Thanks Lucky |
#16
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wrote in message oups.com... Again what about built up static? Static is rf just like any other signal...When you listen to lightning crashes, you are listening to lightning "radio". Now, if you actually have static build up on the antenna, IE from dry weather, etc, you can always add a resister, etc to bleed it off. But hear in TX, I never bother. It's not an issue here. Where does it go then? Where does any other signal go? I usually switch between my 2 antennas to see what brings the frequency in better, the random wire or the dipole. So I don't stay with one fixed antenna all the time. A ground would still not be needed then? No. So I take it most of you not transmitting are not grounded? Well, many do I'm sure, but I don't. I don't use an rf ground to my shack at all. I don't need one. You have basically three types of grounds. The safety ground, the rf ground for the antenna, and the lightning protection ground. Many times the last two are combined. Your power line ground is the "safety ground". You only need a safety ground in the shack, if your radio, etc requires one. If it does require one, it usually will have a third grounding pin on the plug. Many radios do not need a safety ground. Actually these days, *most* radios do not require a safety ground. IE: look at a TV...Do you see a ground pin on the plug? Thats what I thought.... Then you have the RF ground for the antenna. Normally, it should be at or under the antenna, *if* the antenna requires it to complete the antenna. IE: vertical monopoles, etc... If you use a random wire, and ground the shield, it's best to do that outside at the base of the antenna. This assumes a coax feed... On the 24th floor, you will never be able to get a decent RF ground that won't act as an antenna, so thats really your only option. Otherwise, if just a random wire to the radio, I wouldn't bother. If you use a dipole, or other antenna that is complete in itself, there is absolutely no need for an rf ground at the antenna, or the radio. Nada, none, zilch. This is the way I operate. All my antennas are complete, or have rf grounds under them. The lightning ground is purely to direct the strike to ground, and maybe protect the radio, if you want to go that far. There are plenty of threads covering that hornets nest, so you can research that on your own. The lightning ground, I *do* use...But...It's all outside...Has nothing to do with my shack. Grounding is pretty complicated, per the reason/s, and is probably one of the most "wives tales" loaded topics you can find. Inside a 24 th floor highrise, you don't need to worry about static buildup...If you did, probably half the electronics stuff in the place would be toast by now...As far as listening, and static noise, there may well be nothing you can do about it, other than using a coax fed antenna that is outside, and away from the noise source, assuming that source is inside with you. MK Hi MK You gave me a good explanation of how grounding can be classified. What a great post for me, thank you very much. It even answered the questions later in the post I had in my mind from reading the first parts! I always thought a ground was a ground and it had basically only one function: To protect the radio from damage, lower the noise floor and making a complete "radio circuit" So why do these radio manufacturers put grounds on their receivers even when the plug is not 3 prong? I feel better now. I see grounding is not such a 'must have' item. I use a surge protector and it's fused and grounded already since it's 3 prong. I have all my radio gear and even my Astron hooked up to it. So I am grounded for safety already. Plus I have all wires fused too. The dipole and current balun doesn't need a ground, and the random wire is not coax anymore { I couldn't close my window} so grounding that is out too. So since I'm not transmitting it looks like I'm covered. Your post helped me understand all this. Thanks Lucky |
#17
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"Lucky" skrev i en meddelelse ... So what kind of antenna do you think this rectangle aluminum frame makes? What could it be compared to? It would be some strange sort of untuned loop antenna. Actually you could take a look at http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ - a guy from Finland (Greg W) has made use of a window frame as well. He made a small (6") pickup loop from coax cable and uses this with excellent results from 9 to 17 MHz. He has uploaded a video showing the difference between a random wire and his "loop" - impressive. -- Anders Henriksen - born without teeth supermule [at] lite [dot] dk Whosoever is delighted in solitude, is either a wild beast or a god |
#18
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"w_tom" wrote in message ... Do you need an earth ground, or AC electric ground, or just a big Faraday shield? Even your concrete floor is an earth ground - depending on electrical characteristics that were not provided. Without mentioning frequencies or purpose of the 'ground', then all answers will only be speculation based upon personal assumptions. What are you trying to accomplish? Noise reduction? Better signal reception? Human safety? All may be useful or useless reasons for grounding. Lucky wrote: I live on the 23rd floor of a building so I can't use the earth directly for the ground. The options in my "radio room" are the ground from the electrical sockets and that's about it. I've heard I can roll out 10ft of tin foil on the floor as a ground {that's out}, or, use the window frames as a good ground. As far as I can tell, the window frame looks to be aluminum or some sort of alloy. Have any of you heard of using a window frame as a ground? I think I read it in this NG that someone recommended it and was using it for his ground. I've been using the ground from an electrical outlet. But being that so many people live in the building that use appliances and other plugged in items all day and night, I sometimes get what seems like bad feedback affecting the receiver. So what do you think of the window frame for the ground then? I welcome any other options I can use in a room very far from a direct earth ground. The bathroom pipes are all the way across the room separated by a wall. Not easy to get to. Hi Tom I was trying to do the right thing according to manuals and some articles I read, plus lower the noise floor. I always thought this unwanted "noise, static, clicks, lightning and other garbage" needed somewhere to go. That you wanted to provide a path for it so it didn't find it's way to the radios speaker and then your ears. I bascially do BCB during the day, some Hams, shortwave programs during the early night and Hams again later at night. I live in Florida and like listening to the Southern Hams late at night. Some stay on very late. I'm bascially talk programs during the day and all over the night frequencies at night. Whatever catches my interest. I even listen to the Liberty net every so often for fun. Thanks Lucky |
#19
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"Anders Henriksen" wrote in message . .. "Lucky" skrev i en meddelelse ... So what kind of antenna do you think this rectangle aluminum frame makes? What could it be compared to? It would be some strange sort of untuned loop antenna. Actually you could take a look at http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ - a guy from Finland (Greg W) has made use of a window frame as well. He made a small (6") pickup loop from coax cable and uses this with excellent results from 9 to 17 MHz. He has uploaded a video showing the difference between a random wire and his "loop" - impressive. -- Anders Henriksen - born without teeth supermule [at] lite [dot] dk Whosoever is delighted in solitude, is either a wild beast or a god Hi Anders Wow great idea! Yes I can actually see that working very well. In fact I'm going to try it. I have a small pickup loop already made too. Thanks a lot Anders. I'm going to check out his video. Funny how this original ground is turning out to be something I never expected. Thank you Lucky |
#20
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"Anders Henriksen" wrote in message . .. "Lucky" skrev i en meddelelse ... So what kind of antenna do you think this rectangle aluminum frame makes? What could it be compared to? It would be some strange sort of untuned loop antenna. Actually you could take a look at http://groups.yahoo.com/group/Shortwave-SWL-Antenna/ - a guy from Finland (Greg W) has made use of a window frame as well. He made a small (6") pickup loop from coax cable and uses this with excellent results from 9 to 17 MHz. He has uploaded a video showing the difference between a random wire and his "loop" - impressive. -- Anders Henriksen - born without teeth supermule [at] lite [dot] dk Whosoever is delighted in solitude, is either a wild beast or a god Anders, I just saw the two videos. Now that is very impressive. It's not even tuned either from what I can see. My pickup loop is like 6" in length also. Fun stuff for sure Lucky |
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