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Uniden 525 VHF and general question
In article s.com,
"Wilbur Hubbard" wrote: "Bruce in alaska" wrote in message ... 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 You don't read too well, dude. Skippy said the volume of his 'transmission' as heard by other listeners in nearby boats decreased noticeably after about a minute. So the problem is with Skippy's transmitter and not his receiver. If the fuse heats up and the voltage drops and the "low voltage" indicator flashes in the readout as Skippy indicated then that should tell you something. Duh! Wilbur Hubbard Actually it is YOU, Wilbur, who can't read, or does NOT understand the technology that you are talking about. The Deviation of the Modulator in Skip's Transmitter is EXACTLY what we are DISCUSSING and the VOLUME of Skips signal has absolutely NOTHING TO DO with the Power OUT of his Transmitter, but everything to do with the Modulation Deviation of his Transmitter.... This is why a One WAtt Handheld sounds just as loud, in a receiver, as a 25 watt radio, when both signals are above the 12db Quieting Threshold of that receiver.... You just show your ignorance, when you spout off about things you have no Clue about.... -- Bruce in alaska add path after fast to reply |
Uniden 525 VHF and general question
On Mon, 14 Dec 2009 16:03:52 -0900, Bruce in alaska
wrote: Well, it would seem from all the previous posts that there is some controversy about the recommended RF Coax for VHF Marine Installations on various Vessel type.... Hmmmm... Well the answers are fairly straight forward. It really depends on the installation. Small coax, RG58 types, are alright for runs less than 10 Ft. For runs up 100Ft, RG8 Types Should be used. RG213 is better than RG8 or RG8 Foam Core Types, due to Wx survivability, and Water Intrusion. The Price Difference between RG213 and RG214, is usually NOT a cost effective for a NORMAL Marine Installation, especially on a non-Commercial Vessels, where budgets are tight. For Military Installations RG214 is the MINIMUM. On commercial vessels up thru the 80's, RG213 was the standard, for runs under 100 Ft. Thanks Bruce |
Uniden 525 VHF and general question
On Mon, 14 Dec 2009 19:04:12 -0600, brian whatcott
wrote: If a coax gets a 50 ohm lossy resistance, then it soaks up all the power with no reflection. That's where I'm coming from... And so am I. A long length of lossy cable will show no reflected power which translates to an SWR of 1:1. |
Uniden 525 VHF and general question
Wayne.B wrote:
On Mon, 14 Dec 2009 19:04:12 -0600, brian whatcott wrote: If a coax gets a 50 ohm lossy resistance, then it soaks up all the power with no reflection. That's where I'm coming from... And so am I. A long length of lossy cable will show no reflected power which translates to an SWR of 1:1. Then we are agreed that a SWR reading can be misleading in this circumstance. Brian W |
Uniden 525 VHF and general question
On Mon, 14 Dec 2009 23:33:45 -0600, brian whatcott
wrote: Wayne.B wrote: On Mon, 14 Dec 2009 19:04:12 -0600, brian whatcott wrote: If a coax gets a 50 ohm lossy resistance, then it soaks up all the power with no reflection. That's where I'm coming from... And so am I. A long length of lossy cable will show no reflected power which translates to an SWR of 1:1. Then we are agreed that a SWR reading can be misleading in this circumstance. It depends on your expectations. An SWR meter is not the right tool for evaluating the condition/quality of coax. For that you need a stable signal source, a dummy load and a good watt meter like a Bird. The ratio of power in vs power out translates to the loss in dbs with a little calculation. |
Uniden 525 VHF and general question
Bruce in alaska wrote:
If your paying someone to look at you stuff, and he brings anything aboard to check the VHF Antennas other than a Bird Wattmeter with the appropriate Slugs, kick them off your boat as if they had Homeric Fever, because they are Dufus's and will only cost you money. /snip/ If you Google "VHF", sure enough you find entries about Viral Hemorrhagic Fevers (VHFs) like Ebola, Dengue and Marburg. :-) Bird Wattmeters are a trusted article no doubt. If you come up against a strangely absorptive coax, it might just stay absorptive on the Bird, even with the load disconnected. That should provide a clue. Brian W |
Uniden 525 VHF and general question
On 15/12/2009 12:06, brian whatcott wrote:
Bruce in alaska wrote: If your paying someone to look at you stuff, and he brings anything aboard to check the VHF Antennas other than a Bird Wattmeter with the appropriate Slugs, kick them off your boat as if they had Homeric Fever, because they are Dufus's and will only cost you money. /snip/ I can get by with a Hewlett Packard 8754A and Site Master S331D. http://www.us.anritsu.com/products/S...QQSidZ595.aspx If you Google "VHF", sure enough you find entries about Viral Hemorrhagic Fevers (VHFs) like Ebola, Dengue and Marburg. :-) Bird Wattmeters are a trusted article no doubt. If you come up against a strangely absorptive coax, it might just stay absorptive on the Bird, even with the load disconnected. That should provide a clue. Brian W |
Uniden 525 VHF and general question
"Bruce in alaska" wrote in message
... In article s.com, "Wilbur Hubbard" wrote: "Bruce in alaska" wrote in message ... 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 You don't read too well, dude. Skippy said the volume of his 'transmission' as heard by other listeners in nearby boats decreased noticeably after about a minute. So the problem is with Skippy's transmitter and not his receiver. If the fuse heats up and the voltage drops and the "low voltage" indicator flashes in the readout as Skippy indicated then that should tell you something. Duh! Wilbur Hubbard Actually it is YOU, Wilbur, who can't read, or does NOT understand the technology that you are talking about. The Deviation of the Modulator in Skip's Transmitter is EXACTLY what we are DISCUSSING and the VOLUME of Skips signal has absolutely NOTHING TO DO with the Power OUT of his Transmitter, but everything to do with the Modulation Deviation of his Transmitter.... This is why a One WAtt Handheld sounds just as loud, in a receiver, as a 25 watt radio, when both signals are above the 12db Quieting Threshold of that receiver.... You just show your ignorance, when you spout off about things you have no Clue about.... -- Bruce in alaska PKB! You're the one who's clueless. I happen to own one of those crap radios myself and I have discovered all their foibles and failings. You are just operating on theory and your theory is little more than an uninformed guess. So take a hike. When you get some experience with this particular radio perhaps you can return then. Besides, anybody living in Alaska where he gets is ass frozen off most of the year can't be too bright in the first place. Wilbur Hubbard |
Uniden 525 VHF and general question
On Tue, 15 Dec 2009 16:03:54 -0500, "Wilbur Hubbard"
wrote: Actually it is YOU, Wilbur, who can't read, or does NOT understand the technology that you are talking about. The Deviation of the Modulator in Skip's Transmitter is EXACTLY what we are DISCUSSING and the VOLUME of Skips signal has absolutely NOTHING TO DO with the Power OUT of his Transmitter, but everything to do with the Modulation Deviation of his Transmitter.... This is why a One WAtt Handheld sounds just as loud, in a receiver, as a 25 watt radio, when both signals are above the 12db Quieting Threshold of that receiver.... You just show your ignorance, when you spout off about things you have no Clue about.... -- Bruce in alaska PKB! You're the one who's clueless. I happen to own one of those crap radios myself and I have discovered all their foibles and failings. You are just operating on theory and your theory is little more than an uninformed guess. So take a hike. When you get some experience with this particular radio perhaps you can return then. I'm given to understand that the Bruce is an expert in these matters. Besides, anybody living in Alaska where he gets is ass frozen off most of the year can't be too bright in the first place. No reason to drag Sarah Palin into a radio discussion. You should be ashamed of yourself. --Vic |
Uniden 525 VHF and general question
On 13/12/2009 14:53, Flying Pig wrote:
Hi, y'all, I've been active on the cruiser's net here in Abaco, and this morning one of the neighboring boats with a radio and antenna guru aboard called me after to say that after about a minute of continuous transmission I got faint, though still very clear. Another station chimed into the conversation to say they had the same result. *******The original boat is right next to me,**** so distance or atmospheric stuff was not a factor Not a good test as his receiver will be grossly overloaded. Could be the result frequency drift resulting in the IF of the receiver moving off the linear part of the discriminator. Although I still favour the idea that the listener fell asleep. I myself have reached a semi comatose state reading your posts, many times.. |
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