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Short_legs
Junior Member
Username: Short_legs
Post Number: 11
Registered: 12-2008
| | Posted on Wednesday, December 24, 2008 - 5:12 am: | 
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i have a magnum s-6.. the antenna i use is a k-40 trucker seris on a mag mount..i have a swr problem on ch 1 it is a 2.. on ch20 its a i.6 and on ch 40 it is a 1.8.. i have tried to tune the antenna by instructions but cannot get it any lower. could someone give me some suggestions on how to get it lower.. or am i better off just geting a different antenna? |
Tech808
Moderator
Username: Tech808
Post Number: 16387
Registered: 8-2002
| | Posted on Wednesday, December 24, 2008 - 8:04 am: |
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Where do you have the ground wire from the radio grounded?
Most SWR problem's can be solved/resolved with a good ground from the radio to the car frame.
Hope this help's,
Lon~Tech808
CEF#0808/HAM#001/CVC#0002
Tech808@copperelectronics.com
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Moderator136
Moderator
Username: Moderator136
Post Number: 1257
Registered: 4-2005
| | Posted on Wednesday, December 24, 2008 - 7:54 pm: |
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Yes i agree with Tech 808 Its a ground problem.
Mag mounts going though paint and primer will not get you a good ground.
You have to ground it to get swr down!
Good luck Short_legs
Let us know if you get fixed?
Hal~Moderator136~KCØSVC
CEF#0136/CEF HAM#23 ~ CVC#0004
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Short_legs
Junior Member
Username: Short_legs
Post Number: 12
Registered: 12-2008
| | Posted on Thursday, December 25, 2008 - 9:32 pm: |
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i have found nothing out today i checked the swr in the antenna and on ch 1 it is now a 1.. on ch 20 its is a 1.7.. ch 40 is a 3.6.. and yes it is grounded to the car.. i also trimmed the antenna to and nothing has helped.. could someone help please i dont want to ruin this new radio.. |
Tech808
Moderator
Username: Tech808
Post Number: 16392
Registered: 8-2002
| | Posted on Thursday, December 25, 2008 - 11:31 pm: |
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What type of meter are you using to check your SWR?
An external meter or the one in the radio?
Does your SWR Warning light come on?
Does the SWR have the same reading when using both microphone jack's.
Have you tried another antenna?
And where & what do you have your radio grounded to?
Have you checked your coax shield & center conducter from SO239 to the PL259 end that connects to the mag mount and moved it around to see if the SWR stats the same for short's?
Have you checked the Mag Mount itself for short's?
Lon~Tech808
CEF#0808/HAM#001/CVC#0002
Tech808@copperelectronics.com
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Marconi
Advanced Member
Username: Marconi
Post Number: 797
Registered: 11-2001
| | Posted on Friday, December 26, 2008 - 2:38 am: |
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Short Legs, your center frequency went down and you tell us you trimmed the stinger. That does not make sense.
You may have followed some bad advise and cut the stinger, but I agree you have a ground problem. It may, however, have nothing to do with the lack of a good connection or paint if the magnet is working. Mag mounts do not require a physical type connection of the antenna to the vehicle. As long as the magnet works well the capacitance thru the magnetic field created is used for the radiator to work against and provide a return path to ground.
It is a magnet location problem on the vehicle. Try moving the magnet a bit and see if things don't get better. You cut the stinger so it might be too late to see good results. You might have to go a bit higher in frequency now to find a better match.
Good luck and keep us posted. |
Short_legs
Junior Member
Username: Short_legs
Post Number: 13
Registered: 12-2008
| | Posted on Monday, December 29, 2008 - 10:05 pm: |
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i have the radio grounded to the car frame.. and it is a 1.5to 1.6 from ch 1 to ch40 that is on low power..when i turn the power up the swr goes to a 2 or 2.5 1 thru 40.. what would cause that to do that?how could i check the mount for shorts?and no the swr waring light does not come on at all during this process..I have another question where can i find a tune up manuel for a magnum s-6 because the radio i got is only doing about25 watts and i know it should do more and i bought it new.. |
Tech808
Moderator
Username: Tech808
Post Number: 16408
Registered: 8-2002
| | Posted on Monday, December 29, 2008 - 11:56 pm: |
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You can find the alignment information in the area below:
Tools
Mic. Wiring
Frequency Chart
CB & Ham Lingo
Modification List
Manuals
CKICK on Modification List
If you still have probleem's I would suggest you contact Sam Lewis / Magnum International direct for Warranty Repair.
How do I contact Sam Lewis / RF Limited/MAGNUM International direct?direct?
Copper Talk
» Manufacturers Questions
» RF Limited / Magnum
» How do I contact Sam Lewis / RF Limited/MAGNUM International direct?
Lon~Tech808
CEF#0808/HAM#001/CVC#0002
Tech808@copperelectronics.com
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Captian_radio
Advanced Member
Username: Captian_radio
Post Number: 507
Registered: 9-2004
| | Posted on Tuesday, December 30, 2008 - 8:12 am: |
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There is a possibility that what you are seeing is caused by harmonics being generated by the amp,likely cause is the amp does not have proper output filtering and what you are seeing is the result of the 2nd harmonic which is why its showing high swr.Try a low pass filter between the amp and the swr meter and check again.A properly working antenna system will not be affected much extra power, also recalibrate the meter for higher power.
Bob
Robert L. Spicer The days of radio are just beginning!
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Short_legs
Junior Member
Username: Short_legs
Post Number: 14
Registered: 12-2008
| | Posted on Tuesday, December 30, 2008 - 4:30 pm: |
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i am not running a amp on my radio it is the variable power for the radio.. would i still have to put a low pass filter in between the radio and the antenna even if im not running a amp? or would it help my swr if i put one on it? the swr is good on the varible low power 1.5 to a 1.6 is that good? when i turn the varible power up to high it goes up to a 2. something.. it says in the manuel that if it is above 1.5 there is something wrong but the swr warning light does not come on at all during this process.. do i need to just get a different radio? i dont know what to do about this i have run oout of things to try to get this worked out so i dont mess up this radio.. |
Marconi
Advanced Member
Username: Marconi
Post Number: 800
Registered: 11-2001
| | Posted on Tuesday, December 30, 2008 - 5:55 pm: |
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Short Legs, did you know that according to info on Cooper's ad sheet for the S-6 that the High SWR light is controlled by a off/on switch? Are you reading SWR with the meter in the radio or using an inline meter? Are you re-calibrating the SWR meter each time you change the power setting on your radio?
1st Post
Channel SWR
01-2
20-1.6
40-1.8
2nd Post
01-1.0
20-1.7
40-3.6
3rd Post
01-1.5/1.6
20-1.5/1.6
40-1.5/1.6
Different every time you reported SWR. When you trimmed the stinger (report #2) the center frequency went down, which is still the wrong thing that should happen when you shorten the antenna radiator? |
Short_legs
Junior Member
Username: Short_legs
Post Number: 15
Registered: 12-2008
| | Posted on Wednesday, December 31, 2008 - 12:05 am: |
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yes i knew that the swr warning light has a on/ off switch. i am using a in-line meter the radio don't have a swr meter..i am re-calibrating the meter each time i change the power settings.. in the 3 post on the swr readings the first and third one is the same antenna.. the second one is a different one..would it make a difference if the on/ off switch on the swr warning light is on or off when using a in line meter? or do i need to get a different meter to check it? another thing would i have to get a low pass filter for the radio would that bring the swr down on the high power stting on the radio? |
Captian_radio
Advanced Member
Username: Captian_radio
Post Number: 509
Registered: 9-2004
| | Posted on Wednesday, December 31, 2008 - 8:08 am: |
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If no amp dont use a filter, you have an issue with your antenna system, best to sort that out first, try a different antenna and start over.
Bob
Robert L. Spicer The days of radio are just beginning!
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Hotwire
Senior Member
Username: Hotwire
Post Number: 2715
Registered: 1-2005
| | Posted on Thursday, January 01, 2009 - 1:18 pm: |
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Most of the swr readings you posted are not really that bad. A 3.6 is something to look at for losses but a 1.whatever is not a huge deal.Move the antenna to a different spot and the swr meter may read lower. Your not going to fry the radio unless the antenna gets shorted somehow.
Have you got any good radio checks? Is the recieve good and is the transmit range acceptable? You might be worrying for nothing. I read nothing wrong until you trimmed the stinger. Now you may have REAL problems. I would start over with a new antenna. Shorter antennas are harder to tune so the longer the better.
If you have a perfect swr of 1.1 (never really achieved)the antenna is 100% efficient. An swr of 1.5 is 96% efficient, 2.0 is about 90% efficient, 3.0 is about like 75% efficient. These percentages is from a Lou Franklin book so I'm not just pulling them out of my butt.
Nobody on the recieving end will ever be able to tell if you have a 1.1 swr or a 2.1 swr.
We waste so much time fighting to get that 1.1 swr. Sometimes it comes easy sometimes it does not. I have had to work with what I have because the vehicle was not the perfect groundplane for a specific antenna and a 1.5 was the lowest swr I could get no matter what I did...and I talked all over the world.
Kenny
CEF491
Reading the mail around Indianapolis Indiana!
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