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Watchman
Posted on Saturday, October 11, 2003 - 3:54 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Can someone explain the power multiplication table to me.....I was interested in the Maco 108 8 beam base antenna.....Someone told me that the power multiplication table was, whatever you put out from the radio and amp(if you got one) it would be multiplied by how many times the antenna is boasting it will do...ie...maco 108 8 beam boasts a 60x multiplication table...So if I put out 500watts deadkey would that mean I put out 30kw out the antenna? Any reponses will be greatly appreciated. Thanks for the help....A newbie to the radio world...Sincerely, Watchman555 So. Calif.
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Bruce
Posted on Saturday, October 11, 2003 - 8:32 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

watchman

As Joe Friday used to say her are the facts!

POWER multiplication table

3db = 2X
6db = 4X
9db = 8X
10db= 10X
13db= 20X
16db= 40X
19db= 80X
20db= 100X
30db= 1000X

real world gain for a 3 elm beam is about 6-8 DBD or 4 to 7X

A 6 elm beam is 9-11 DBD or 8-12X

a 8 elm beam is 11-13 DBD or 12-20X

i think you will find this is more the truth.
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Watchman
Posted on Saturday, October 11, 2003 - 11:53 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey Bruce thanks for the response.....But you are talking spanish to me....Can you explain it in laymens terms? So from the 8 element maco 108 base antenna I can expect a true 12-20x mutilpication? ie....500watts deadkeyx20=10kw out the antenna? Would that be 10,000 watts of true power and if it is then, the antenna is really more impotant than the amp.....realistically speaking. So why dont people bother upgrading there antenna before stepping up the power of there amps? Any help on this issue is greatly appreciated.....I am really interested in getting the proper information regarding this issue before I spend alot of money, perhaps on something not really needed.
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Cactusjack
Posted on Sunday, October 12, 2003 - 12:37 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

hi watchman,

Not to change the subject but it's nice to see someone else on the forum from so. calif, and real close to me too. I'm in vista.

Glad to see you on the forum.

Cactusjack/CEF124

P.S. Have you heard about our CEF (Copper Electronics Forum) net we have on sunday mornings?
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Scrapiron63
Posted on Sunday, October 12, 2003 - 10:41 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Watchman, those are good questions and points your making about why people don't upgrade antennas instead of power. I've asked cb'ers that for 30 years. I guess it's too much work or impossible for some to install towers and bigger antennas, but just raising them higher would make lots of difference. It's easier to stick that A99 up about 20 feet with cheap coax, and buy that bigger amp. Then wonder why your bothering all the neighbors plus all the other radio operators within 50 miles. You wouldn't believe the people i've known over the years in really close living conditions, like trailer parks and apartment complexes, that would stick up a GP barely over the roof with rg-58 or mini-8 coax, and try running a 500-1000+ watt amplifier. Sure they get in trouble, they'er just asking for it. And we wonder why CB'ers have such a bad name with lots of people. scrapiron
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Watchman
Posted on Monday, October 13, 2003 - 1:00 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

First off I thank you both for responses. CactusJack I did not know that there is a forum on Sunday morning.....Any info on how to join or where to go would definitly be cool...And by the way Iam in Ontario, Ca.....My family lives in Vista.....Anyways Scrapiron63 I appreciate your feedback in regards to my questions.....But I am still going to check this posting until I have an answer to my question.....LOL.....I really would like the correct info regarding the power multiplication and how it really works....I want the best antenna Ican get especially if it is going to multiply my power.....Anyways if there is anyone out there that can help me this it will be greatly appreciated......73's...Watchman so. calif.
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Crafter
Posted on Monday, October 13, 2003 - 2:12 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Watchman yes your right! The trick is to use a high gain antenna up at least 36 feet and your right on. Also like scarp-iron said use good coax good connectors every little bit helps reduce pwr loss.
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Watchman
Posted on Monday, October 13, 2003 - 12:43 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Crafter.....Well if I can gain a minimum of 6kw out my measley 500 watts deadkey, I guess I'll go with the maco 8 element beam. Unless anyone out there has a better selection in about the same price range, and of course it would have to have at least that 60x multiplication power. I apppreciate all the feedback in here it is just fantastic. 73's yall.....Watchman.......Sunny So. California
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Cactusjack
Posted on Monday, October 13, 2003 - 7:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

watchman,

Here is where to find all the CEF net info: On the main forum page click on "CEF NET CONNECTIONS" enter your user name and password, then Click on "NEW CEF NET COPPER ELECTRONICS FORUM NET" at the top of the page.

Hope to hear you on the net.
73's
cactusjack/CEF124
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Bruce
Posted on Monday, October 13, 2003 - 8:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

the gain is 2 way you also gain on receive
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Mr_Rf
Posted on Monday, October 13, 2003 - 10:54 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Watchman, to add to Bruce's response. The antenna gain also holds true for recieve. If you ask the experts this is what they will tell you...On a receiver's properly calibrated S-Meter every 6 to 7 dB (decibels) of antenna gain equates to 1 S-unit increase on the s-meter.

Example: If you have an 8 Element antenna with 12 to 14 dB gain, you should see an increase of about 2 S-Units on your S-meter...when compared to a basic groundplane antenna.

Bottom line, more can be had from a good antenna than a amp any day, not to mention the ability to reduce the signal strength of unwanted signals on the side and back of a beam!
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Watchman
Posted on Tuesday, October 14, 2003 - 12:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hey thanks for responses guys. All the info I have gathered here in this forum and others has brought me to the conclusion I need a new antenna. I would have done this to begin with if I really knew how important a bigger antenna really was. Copper and its followers will definatly be a part of my ambition to get my operators liscense and continue my love for the radio world. My hats off to all the techs and radio enthusiasts alike. When I get my new antenna up and everything dialed in, I will be joining in on the Sunday CEF net call. Hope to hear you guys out there. 73's yall.....and have a great upcoming holiday...Sincerely, Watchman555 So. Calif.
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Mikefromms
Posted on Friday, January 02, 2004 - 11:44 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Watchman, you will hear things out there on that 8 element you never knew existed on the groundplane. I have a much smaller beam than that and I can hear things I didn't know were out there with the plain old GP. True increases in db gain mean a lot on tranmit and recieve. It's not just measured by the s-unit standard either. You can hear stuff that doesn't move the meter.

mikefromms

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