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#11
posted to rec.boats.cruising
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VHF installation questions
Roger's post said he's "looking for more range" than a handheld can
provide; the only way to feel good about an 'installed' VHF (assume mast mounted antenna) system is to know that the antenna is 'accepting' all of the power delivered to it (as opposed to 'rejecting', or 'reflecting' some of it back to the transmitter - a rough definition of 'Standing Waves'). If you know any Ham (Amateur Radio) operators, ask if you can borrow their "Bird Model 43" thruline wattmeter. Easy to use, and the results will provide peace of mind about your new radios ability to provide "more range." Note: Because receivers are so sensitive these days, even a very poorly matched antenna will likely result in a "sounds ok to me skipper" radio check. This seems to me to be a poor way to check a vital piece of safety equipment... MW Los Angeles |
#12
posted to rec.boats.cruising
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VHF installation questions
I just called a marine electronics shop and they said to "just do a
radio check". Couldn't tell me if there was a preferred channel in this area such as is reported for the West Coast (22 A). Maybe if I'd bought the radio from them -- Roger Long wrote in message oups.com... Roger's post said he's "looking for more range" than a handheld can provide; the only way to feel good about an 'installed' VHF (assume mast mounted antenna) system is to know that the antenna is 'accepting' all of the power delivered to it (as opposed to 'rejecting', or 'reflecting' some of it back to the transmitter - a rough definition of 'Standing Waves'). If you know any Ham (Amateur Radio) operators, ask if you can borrow their "Bird Model 43" thruline wattmeter. Easy to use, and the results will provide peace of mind about your new radios ability to provide "more range." Note: Because receivers are so sensitive these days, even a very poorly matched antenna will likely result in a "sounds ok to me skipper" radio check. This seems to me to be a poor way to check a vital piece of safety equipment... MW Los Angeles |
#13
posted to rec.boats.cruising
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VHF installation questions
On Thu, 27 Jul 2006 13:28:08 GMT, "Roger Long"
wrote: I just called a marine electronics shop and they said to "just do a radio check". Couldn't tell me if there was a preferred channel in this area such as is reported for the West Coast (22 A). Maybe if I'd bought the radio from them Make a call to a specific vessel or shore station (marina, yacht club, SEATOW, etc.), on either ch 16 or 9. Otherwise you can buy your own SWR bridge for about $40. |
#14
posted to rec.boats.cruising
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VHF installation questions
Sorry Chuck, but with frequency modulation (used with marine VHF
radios), the 'loudness' of a received signal has *nothing to do* with the transmitter's power output or quality of the antenna system. Asking "can you hear me now?" of a fellow mariner in the same harbor seems a dubious way of checking the integrity of a vital communications system. The most likely failure mechanism for an 'old' coax is water migration into the cable - which generally happens at the antenna connection. This *will* change the impedance of the cable, which *will* show up on the thruline, or VSWR meter. "Old coax" in and of itself usually doesn't "become lossy" simply becuase of it's age; 100 year old copper conducts just as freely as 'new' copper. MW chuck wrote: I don't think Roger is too interested in measurements, though, and there is a lot of wisdom in the notion that if you want to know if your big VHF is louder than your handheld VHF, the best way to find out is to see if it IS louder. ;-) |
#15
posted to rec.boats.cruising
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VHF installation questions
"Wayne.B" wrote in message
... On Thu, 27 Jul 2006 00:14:14 -0700, "Capt. JG" wrote: Here? I sail in the SF area. They don't like being hailed for radio checks, and you can't hail on 22a. A popular radio check strategy around here is to call SeaTow on channel 16, switch to a working channel, and ask for a signal report. They seem to be OK with it, and it is a legit use of 16. I agree... calling SeaTow is a reasonable thing to do. If nothing else, free advertising for them. :-) -- "j" ganz @@ www.sailnow.com |
#17
posted to rec.boats.cruising
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VHF installation questions
In article BxWxg.248882$IK3.66723@pd7tw1no,
Gary wrote: Like I said, here the Coast Guard tell you to call on 22a. It may be different where you are. The advantage of a Coast Guard radio check is the can check your signal on a variety of repeaters and tell you how far you are going. They can even DF you! Receiving poor signals may be neccessary if your radio isn't working properly, and they'll tell you that too. Bzzzt, Wrong Information..... Maybe the Canadian Coast Guard can do what you say, but the USCG is about 10 years behind in DCS and Vhf DF Deployment, and do NOT have that capability on most of the US Coastline. Yes, they do have a good VHF HighSite Deployment but these are not DCS or DF Capable, for the most part, and will not be for a few more years. The congress wants the USCG to be watching for Terrorists not answering Distress Calls from Idiot Yatchmen. |
#18
posted to rec.boats.cruising
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VHF installation questions
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