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Old 03 August 2007, 21:06   #11
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There is a big difference between being able to receive and transmit. Your transmit capability is dependant on the height of your aerial, the height of the receiving aerial AND the Db of your aerial. ( effects transmit pattern)
High Db is good. Those stupid little 3 ft. whip aerials which are only 3Db are only good for strapping to a rubber duck in a pond. 8 ft, 6 Db. aerial is the best for a RIB in my opinion.

Of course, Codders is going to disagree as usual and come up with some super tech. explanation of the subject.
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Old 04 August 2007, 06:02   #12
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An 8ft 6db arial would look a little silly on my 4.8 RIB, it would look like big a radio controlled toy boat!
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Old 04 August 2007, 08:08   #13
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There is a big difference between being able to receive and transmit. Your transmit capability is dependant on the height of your aerial, the height of the receiving aerial AND the Db of your aerial. ( effects transmit pattern)
High Db is good. Those stupid little 3 ft. whip aerials which are only 3Db are only good for strapping to a rubber duck in a pond. 8 ft, 6 Db. aerial is the best for a RIB in my opinion.

Of course, Codders is going to disagree as usual and come up with some super tech. explanation of the subject.
Not really.........
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Old 04 August 2007, 08:21   #14
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There is a big difference between being able to receive and transmit. ....

...Of course, Codders is going to disagree as usual and come up with some super tech. explanation of the subject.
No, it'll be me. I believe an antenna is equally good at receiving as it is at transmitting. However, there are other factors which come into play that may influence a signal and enable you to receive it.
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Old 04 August 2007, 09:53   #15
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VHF also is a "line of sight" frequency, that means that the signal drops expenentually if line of sight isn't acheived. I think I remember right that at a hieght of 6' from Sea level the horizon is only 3 miles away. so that means that two RIBs trying to contact each other with arials of no higher that 6' from Sea level will have trouble contacting each other of say more than about 10 miles apart. There are other factors such as signal reflection etc but that is too heavy for me.
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Old 04 August 2007, 10:36   #16
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The link below provides good info. on this subject. Of course the sytem chosen depends alot on type of use and personal preferences. Personaly I prefer stuff that works at max. possible performance.
http://www.westmarine.com/webapp/wcs...HFAntennas.htm
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Old 04 August 2007, 11:30   #17
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More good info. on this site
http://www.catfleet21.org/rigging/June.htm
T.
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Old 04 August 2007, 11:44   #18
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And so Codders does not get bored. Here is some real techy. stuff
http://continuouswave.com/whaler/reference/VHF.html
I am VHFed out for today.
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Old 04 August 2007, 11:48   #19
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Originally Posted by Limey Linda View Post
And so Codders does not get bored. Here is some real techy. stuff
http://continuouswave.com/whaler/reference/VHF.html
I am VHFed out for today.
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Old 04 August 2007, 16:44   #20
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And so Codders does not get bored. Here is some real techy. stuff
http://continuouswave.com/whaler/reference/VHF.html
I am VHFed out for today.
To be honest I did get bored - started studying for my amateur radio exams but gave up on them - much more fun to mess around with directed energy radio waves - amazing what they can do to computers and other lectronics......
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