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Uniden 525 VHF and general question
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. |
Uniden 525 VHF and general question
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" |
Uniden 525 VHF and general question
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 |
Uniden 525 VHF and general question
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". |
Uniden 525 VHF and general question
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. Total loss: an often heard squawk about rubber duckies. But it is not all that easy to maintain a 50 ohm impedance AND soak up most of the transmit power with salt water in a coax - so a SWR meter has merit IF and only IF it is suited to the frequency band in use. Most hams use swr tests under 30 MHz. Brian W |
Uniden 525 VHF and general question
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? |
Uniden 525 VHF and general question
On Mon, 14 Dec 2009 11:57:59 -0600, brian whatcott
wrote: it is not all that easy to maintain a 50 ohm impedance AND soak up most of the transmit power with salt water in a coax If the coax is soaking most of the transmit power it doesn't really matter what impeadance it is. An SWR meter will still show no reflected power, hence a 1:1 ratio. |
Uniden 525 VHF and general question
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.. |
Uniden 525 VHF and general question
In article s.com,
"Wilbur Hubbard" wrote: "Wayne.B" wrote in message ... Agreed but you could have a bad connection which is heating up under load. BINGO! They use one of those crap, 'slow burn' fuses. They heat up and the extra impedance reduces the voltage. Get rid of it and put a higher amperage rated, fast burn fuse in - end of problem. Wilbur Hubbard Bull****.... Wilbur, you need to stick to stuff you know about.... as Peter Bennett pointed out, if the volume at the receiver dropped, but the background noise didn't change, then the problem is in the Modulating Deviation, not the Power Output.... This is FM not AM or SSB.... In FM, once you exceed 12 db of Receiver Quieting the Background Noise, changes are hardly perceptible, and in FM, the volume produced in the receiver is directly proportional to the Modulation Deviation of the Transmitter, until it exceeds the bandwidth of the Receiver. -- Bruce in alaska add path after fast to reply |
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