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On Sun, 13 Dec 2009 23:48:25 -0500, Wayne.B
wrote: On Sun, 13 Dec 2009 15:14:31 -0500, "Flying Pig" wrote: I'll try to find someone with a SWR meter here tomorrow morning before we head out to our anchorage prior to going into the dock where we'll be leaving Flying Pig, and give it a whirl. One of the quirks of waterlogged coax is that it can exhibit a perfect 1:1 SWR ratio while transmitting little or no power because the signal loss is so high that nothing gets reflected back to the SWR meter. I also have the little cable and the mast-top antenna which proved the cable at fault in the original explorations; it will be easy for me to get a boat buddy to listen while I read some story or something on a remote channel and see if that cured it. That shortie, BTW, is LMR400, so should be fine for the test. I don't expect it's got much in the way of SWR issues :{)) OK As to sagging power, with an 880AH bank, I doubt that's a problem, Agreed but you could have a bad connection which is heating up under load. Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. |
#2
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#4
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On Mon, 14 Dec 2009 15:35:08 +0000, goofball_star_dot_etal
wrote: Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. Probably a Ham's old wives' tale. Your average VSWR meter is not very accurate, although still quite useful. This leads to all sorts of BS. The device I use cost more than my boat.. Nope, not an old wives tale at all. Do you have a rational explanation then? I think the dog is peeing on the fire hydrant in an attempt at humor. If not he's barking up the wrong tree. |
#5
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On 14/12/2009 15:46, Wayne.B wrote:
On Mon, 14 Dec 2009 15:35:08 +0000, goofball_star_dot_etal wrote: Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. Probably a Ham's old wives' tale. Your average VSWR meter is not very accurate, although still quite useful. This leads to all sorts of BS. The device I use cost more than my boat.. Nope, not an old wives tale at all. Do you have a rational explanation then? I think the dog is peeing on the fire hydrant in an attempt at humor. If not he's barking up the wrong tree. I think you mean "****ing into the wind" |
#6
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On 14/12/2009 15:28, wrote:
On Mon, 14 Dec 2009 15:15:48 +0000, goofball_star_dot_etal wrote: On 14/12/2009 11:00, wrote: On Sun, 13 Dec 2009 23:48:25 -0500, Wayne.B wrote: On Sun, 13 Dec 2009 15:14:31 -0500, "Flying Pig" wrote: I'll try to find someone with a SWR meter here tomorrow morning before we head out to our anchorage prior to going into the dock where we'll be leaving Flying Pig, and give it a whirl. One of the quirks of waterlogged coax is that it can exhibit a perfect 1:1 SWR ratio while transmitting little or no power because the signal loss is so high that nothing gets reflected back to the SWR meter. I also have the little cable and the mast-top antenna which proved the cable at fault in the original explorations; it will be easy for me to get a boat buddy to listen while I read some story or something on a remote channel and see if that cured it. That shortie, BTW, is LMR400, so should be fine for the test. I don't expect it's got much in the way of SWR issues :{)) OK As to sagging power, with an 880AH bank, I doubt that's a problem, Agreed but you could have a bad connection which is heating up under load. Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. Probably a Ham's old wives' tale. Your average VSWR meter is not very accurate, although still quite useful. This leads to all sorts of BS. The device I use cost more than my boat.. Nope, not an old wives tale at all. Work out the _magnitude_ of the change in electrical length of the antenna due to water vapour for yourself. http://www.kayelaby.npl.co.uk/genera...2_5/2_5_7.html |
#7
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posted to rec.boats.cruising
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On 14/12/2009 17:48, wrote:
On Mon, 14 Dec 2009 17:33:33 +0000, goofball_star_dot_etal wrote: On 14/12/2009 15:28, wrote: On Mon, 14 Dec 2009 15:15:48 +0000, goofball_star_dot_etal wrote: On 14/12/2009 11:00, wrote: On Sun, 13 Dec 2009 23:48:25 -0500, Wayne.B wrote: On Sun, 13 Dec 2009 15:14:31 -0500, "Flying Pig" wrote: I'll try to find someone with a SWR meter here tomorrow morning before we head out to our anchorage prior to going into the dock where we'll be leaving Flying Pig, and give it a whirl. One of the quirks of waterlogged coax is that it can exhibit a perfect 1:1 SWR ratio while transmitting little or no power because the signal loss is so high that nothing gets reflected back to the SWR meter. I also have the little cable and the mast-top antenna which proved the cable at fault in the original explorations; it will be easy for me to get a boat buddy to listen while I read some story or something on a remote channel and see if that cured it. That shortie, BTW, is LMR400, so should be fine for the test. I don't expect it's got much in the way of SWR issues :{)) OK As to sagging power, with an 880AH bank, I doubt that's a problem, Agreed but you could have a bad connection which is heating up under load. Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. Probably a Ham's old wives' tale. Your average VSWR meter is not very accurate, although still quite useful. This leads to all sorts of BS. The device I use cost more than my boat.. Nope, not an old wives tale at all. Work out the _magnitude_ of the change in electrical length of the antenna due to water vapour for yourself. http://www.kayelaby.npl.co.uk/genera...2_5/2_5_7.html Oh, so you now acknowledge that it DOES make a difference... Okay! Yes, but it is "**** all". |
#8
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posted to rec.boats.cruising
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On 14/12/2009 18:24, wrote:
On Mon, 14 Dec 2009 17:50:24 +0000, goofball_star_dot_etal wrote: On 14/12/2009 17:48, wrote: On Mon, 14 Dec 2009 17:33:33 +0000, goofball_star_dot_etal wrote: On 14/12/2009 15:28, wrote: On Mon, 14 Dec 2009 15:15:48 +0000, goofball_star_dot_etal wrote: On 14/12/2009 11:00, wrote: On Sun, 13 Dec 2009 23:48:25 -0500, Wayne.B wrote: On Sun, 13 Dec 2009 15:14:31 -0500, "Flying Pig" wrote: I'll try to find someone with a SWR meter here tomorrow morning before we head out to our anchorage prior to going into the dock where we'll be leaving Flying Pig, and give it a whirl. One of the quirks of waterlogged coax is that it can exhibit a perfect 1:1 SWR ratio while transmitting little or no power because the signal loss is so high that nothing gets reflected back to the SWR meter. I also have the little cable and the mast-top antenna which proved the cable at fault in the original explorations; it will be easy for me to get a boat buddy to listen while I read some story or something on a remote channel and see if that cured it. That shortie, BTW, is LMR400, so should be fine for the test. I don't expect it's got much in the way of SWR issues :{)) OK As to sagging power, with an 880AH bank, I doubt that's a problem, Agreed but you could have a bad connection which is heating up under load. Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. Probably a Ham's old wives' tale. Your average VSWR meter is not very accurate, although still quite useful. This leads to all sorts of BS. The device I use cost more than my boat.. Nope, not an old wives tale at all. Work out the _magnitude_ of the change in electrical length of the antenna due to water vapour for yourself. http://www.kayelaby.npl.co.uk/genera...2_5/2_5_7.html Oh, so you now acknowledge that it DOES make a difference... Okay! Yes, but it is "**** all". Here is what I said: Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. After much huffing, puffing and posturing, you now admit that statement was absolutely correct. Apology accepted. Still not worked out how much the centre frequency shifts compared to the typical 2Mhz bandwidth? |
#9
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posted to rec.boats.cruising
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On 14/12/2009 18:33, wrote:
On Mon, 14 Dec 2009 18:30:49 +0000, goofball_star_dot_etal wrote: On 14/12/2009 18:24, wrote: On Mon, 14 Dec 2009 17:50:24 +0000, goofball_star_dot_etal wrote: On 14/12/2009 17:48, wrote: On Mon, 14 Dec 2009 17:33:33 +0000, goofball_star_dot_etal wrote: On 14/12/2009 15:28, wrote: On Mon, 14 Dec 2009 15:15:48 +0000, goofball_star_dot_etal wrote: On 14/12/2009 11:00, wrote: On Sun, 13 Dec 2009 23:48:25 -0500, Wayne.B wrote: On Sun, 13 Dec 2009 15:14:31 -0500, "Flying Pig" wrote: I'll try to find someone with a SWR meter here tomorrow morning before we head out to our anchorage prior to going into the dock where we'll be leaving Flying Pig, and give it a whirl. One of the quirks of waterlogged coax is that it can exhibit a perfect 1:1 SWR ratio while transmitting little or no power because the signal loss is so high that nothing gets reflected back to the SWR meter. I also have the little cable and the mast-top antenna which proved the cable at fault in the original explorations; it will be easy for me to get a boat buddy to listen while I read some story or something on a remote channel and see if that cured it. That shortie, BTW, is LMR400, so should be fine for the test. I don't expect it's got much in the way of SWR issues :{)) OK As to sagging power, with an 880AH bank, I doubt that's a problem, Agreed but you could have a bad connection which is heating up under load. Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. Probably a Ham's old wives' tale. Your average VSWR meter is not very accurate, although still quite useful. This leads to all sorts of BS. The device I use cost more than my boat.. Nope, not an old wives tale at all. Work out the _magnitude_ of the change in electrical length of the antenna due to water vapour for yourself. http://www.kayelaby.npl.co.uk/genera...2_5/2_5_7.html Oh, so you now acknowledge that it DOES make a difference... Okay! Yes, but it is "**** all". Here is what I said: Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. After much huffing, puffing and posturing, you now admit that statement was absolutely correct. Apology accepted. Still not worked out how much the centre frequency shifts compared to the typical 2Mhz bandwidth? Hey, you were wrong. Man up and move on. Ask someone to work it out for you.. |
#10
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posted to rec.boats.cruising
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On 14/12/2009 19:06, wrote:
On Mon, 14 Dec 2009 18:51:00 +0000, goofball_star_dot_etal wrote: On 14/12/2009 18:33, wrote: On Mon, 14 Dec 2009 18:30:49 +0000, goofball_star_dot_etal wrote: On 14/12/2009 18:24, wrote: On Mon, 14 Dec 2009 17:50:24 +0000, goofball_star_dot_etal wrote: On 14/12/2009 17:48, wrote: On Mon, 14 Dec 2009 17:33:33 +0000, goofball_star_dot_etal wrote: On 14/12/2009 15:28, wrote: On Mon, 14 Dec 2009 15:15:48 +0000, goofball_star_dot_etal wrote: On 14/12/2009 11:00, wrote: On Sun, 13 Dec 2009 23:48:25 -0500, Wayne.B wrote: On Sun, 13 Dec 2009 15:14:31 -0500, "Flying Pig" wrote: I'll try to find someone with a SWR meter here tomorrow morning before we head out to our anchorage prior to going into the dock where we'll be leaving Flying Pig, and give it a whirl. One of the quirks of waterlogged coax is that it can exhibit a perfect 1:1 SWR ratio while transmitting little or no power because the signal loss is so high that nothing gets reflected back to the SWR meter. I also have the little cable and the mast-top antenna which proved the cable at fault in the original explorations; it will be easy for me to get a boat buddy to listen while I read some story or something on a remote channel and see if that cured it. That shortie, BTW, is LMR400, so should be fine for the test. I don't expect it's got much in the way of SWR issues :{)) OK As to sagging power, with an 880AH bank, I doubt that's a problem, Agreed but you could have a bad connection which is heating up under load. Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. Probably a Ham's old wives' tale. Your average VSWR meter is not very accurate, although still quite useful. This leads to all sorts of BS. The device I use cost more than my boat.. Nope, not an old wives tale at all. Work out the _magnitude_ of the change in electrical length of the antenna due to water vapour for yourself. http://www.kayelaby.npl.co.uk/genera...2_5/2_5_7.html Oh, so you now acknowledge that it DOES make a difference... Okay! Yes, but it is "**** all". Here is what I said: Accurate SWR measurements also require clear dry conditions. An overcast day will affect the readings. After much huffing, puffing and posturing, you now admit that statement was absolutely correct. Apology accepted. Still not worked out how much the centre frequency shifts compared to the typical 2Mhz bandwidth? Hey, you were wrong. Man up and move on. Ask someone to work it out for you.. Wussy! It's about the same magnitude as shaving 2 thou off a 3ft. dipole, at most, unless I made a mistake doing it in my head.. Besides, shouldn't you tune for typical conditions not for Antarctica. This link I came across might be of interest to some. http://www.mike-willis.com/Tutorial/refraction.htm |
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