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Cadilac
Junior Member
Username: Cadilac

Post Number: 22
Registered: 1-2006
Posted on Thursday, April 20, 2006 - 7:40 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

This forum is really cool. I live in an apartment complex so it's kind of tricky doing the antena thing. Management doesn't want anything on the balconys, but I used to throw my magmount out there when the rent office is closed and on weekends. This place is like CB away from CB. Keep up the good work.

CADILAC
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Sniper_62881
Member
Username: Sniper_62881

Post Number: 62
Registered: 7-2005
Posted on Thursday, April 20, 2006 - 8:12 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I used to have a mobile antenna on a cookie sheet and that worked good with bout 1.5 SWR reading. Worked good for local not sure about DX.

marc/cef613
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Cadilac
Junior Member
Username: Cadilac

Post Number: 25
Registered: 1-2006
Posted on Thursday, April 20, 2006 - 8:50 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Hi Sniper, I just got your message. You mentioned having the cr antena on a cookie sheet with a 1.5 swr. That leds me to a question. What is a really bad swr? I ask this because when I used to live in Northern VA wit my grandfather who is a cber also, our swrs stayed arround 1.1 at worst, for the most part they stayed arrount 0. I kinda grew to believe if they got to 1.5 or higher that was a verry bad thing.

CADILAC
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Sniper_62881
Member
Username: Sniper_62881

Post Number: 63
Registered: 7-2005
Posted on Thursday, April 20, 2006 - 8:59 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

well to my knowledge anythng over 1.5 is not too good. But maybe you should try that not a bad temporary solution. If you like it you can thank Hal.
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Rover
Intermediate Member
Username: Rover

Post Number: 365
Registered: 2-2004
Posted on Thursday, April 20, 2006 - 9:18 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Actually, no. It is *nice* to get to 1.5 or below, but even 1.7 ain't too bad. You will not be able to tell the difference, really, in 1.1 or 1.7 (signalwise). So if you CAN'T get below 1.6 or 7, I wouldn't sweat it TOO much. Perhaps, when the wife/girlfriend isn't patting her foot for you come on and let's GO, you can come back and get it down more.

BTW, it's not important, just thought I'd mention it. There are no "SWR'ssssssssssss" in a feedline. There is ONE Standing Wave Ratio in ONE feedline. :-) Just pickin'! :-)
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Chad
Advanced Member
Username: Chad

Post Number: 788
Registered: 11-2004


Posted on Thursday, April 20, 2006 - 9:40 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Yeah 1.5 is actually great when you understand what SWR is and how to calculate the percentage of reflected power. Roll with it.

Chad
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Patrick26062
New member
Username: Patrick26062

Post Number: 2
Registered: 3-2006
Posted on Thursday, April 20, 2006 - 9:52 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I live in an apartment second floor. I went with a inverted v dipole. Works fine so far.
Patrick
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Tech237
Moderator
Username: Tech237

Post Number: 294
Registered: 4-2004
Posted on Friday, April 21, 2006 - 8:16 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Anything under 2:1 is usuable, depending o the radio, but it is nice to stay less than 1.5:1. Bear in mind the SWR yuo see at the CB may not, and probably isn't the correct SWR.

The only real place to accurately measure SWR is right at the base of the antenna.

As for an antenna try an indoor loop mounted to teh room ceiling.
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Dale
Intermediate Member
Username: Dale

Post Number: 344
Registered: 12-2002
Posted on Saturday, April 22, 2006 - 5:39 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

tech 237 you mean with an anlizer
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2ec837
Intermediate Member
Username: 2ec837

Post Number: 120
Registered: 12-2001
Posted on Friday, November 10, 2006 - 5:49 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

SWR is the most is the most understood thing in the CB hobby. I was always told a perfect match was 1.1:1. I used a 5/8 GP that the clamp had broke and the top of the vertical element had slid down with a SWR of over 4:1.the local range didn't seem very affected and I was even able to work DX.
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Starface
Advanced Member
Username: Starface

Post Number: 874
Registered: 1-2005


Posted on Friday, November 10, 2006 - 11:30 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

No offence but running a radio with a 4:1 ratio isn't the smartest thing to be doing, sure it with work but the question is for how long?
Best find a way to get it back under 1.5:1 ratio
Or poof there goes the radio.
If you can't get it back down then a replacement is the only other thing to do... plain and simple..

Starface
CEF476
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2ec837
Intermediate Member
Username: 2ec837

Post Number: 121
Registered: 12-2001
Posted on Saturday, November 11, 2006 - 4:16 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

No offense taken,I've been in the radio hobby long enough too know this isn't the smartest thing to do.This was sort of a test to see hoe long it would last.I used a $5 garage sale radio so if it did go so south it was no great loss.After a month or so of regular use the rig was still working fine.The antenna was re-tuned for 46 MHZ and put on the roof as a dedicated VHF Low-Band scanner antenna.
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Hollowpoint445
Senior Member
Username: Hollowpoint445

Post Number: 1407
Registered: 6-2004
Posted on Saturday, November 11, 2006 - 7:28 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

If the radio will tolerate the 4:1 VSWR there really isn't a problem. Actually, as long as the radio hasn't been tuned to more than standard power levels, most radios will tolerate quite a high VSWR as long as the impedance is high. If it's low, then it would be more likely to have a problem. With the 5/8 wave antenna mentioned before, the impedance was probably high because the matching device on a 5/8 wave antenna lowers the impedance.

In The Screwdriver Expert's Guide, Lou Franklin writes that he's intentionally shorted the coax with some radios keyed, and also left radios keyed with no antenna attached at all, and in both circumstances the radios were not harmed. He explains that radios have high VSWR protection circuits that kept the transistors from blowing.

The obsession with low VSWR is probably because most CBers get their radios peaked out. Transistors will only tolerate a certain amount of voltage. When VSWR is high, reflected signal raises the voltage at certain points along the coax, and at those points the voltage can be high enough to blow the final transistor and sometimes the driver too. That's how an antenna tuner protects a radio from a poor VSWR - it lowers the voltage to the radio's finals so it can tolerate a bad antenna match.
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Test_bot
Junior Member
Username: Test_bot

Post Number: 17
Registered: 3-2006
Posted on Monday, November 13, 2006 - 8:06 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

A Cookie Sheet hehe, I never would have thought of that....
Thats a great idea, I am assuming a round one?
What size did you use, and what size mobile antenna? Whip?

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