NEWB...swr question re:257HP

[Whiplash-265]

Hi all...

new here and curious about a swr reading that i'm getting on my very recently installed Magnum 257HP (which i bought after reading a review here and on CBrm)

anyway, details:
Magnum 257HP and Wilson5000 magnet mount
with power down i'm getting a beautiful 1:1 on all CB stations..kick up the power and it swings form 1.5 on ch.1 thru to 2.5 on ch.40

just wondering if this is normal with the addition of power? or have i muffed something up...
also is it still safe to operate at those levels
hopefully a quick and easy fix cuz it's an in-dash install

thanx in advance

 

[W5LZ]

The first thing is, are you using a built in SWR meter, or and external one? And, are you recalibrating it for the higher power level?
Power won't cause SWR to go up. A change in power level can cause an SWR meter yo not read correctly if it isn't recalibrated. A typical 'internal'/built-in SWR meter probably doesn't have a means of doing that calibrating...
- 'Doc

 

[Superidgit]

Hey welcome to the boards.

Are you using an external SWR meter when you are doing the testing?

Any way you could swap out the Coax, the antenna, and/or both?

Heres a link that I found here that may give you some ideas that you could check out also.

http://www.worldwidedx.com/cb-antennas/56747-high-swr-when-more-power-added.html

Good Luck!!

EDIT:

Guess I was postin about same time as W5LZ

 

[Whiplash-265]

thanx for the replies guys

yes, using an external meter..and was re-calibrating between the low and high power adjustments


will have a look at the link Superidgit, appreciate it

 

[Whiplash-265]

missed a part of your reply Superidgit

i still have a pair of 4' firestix installed on the truck that i could hook up and try
can anyone suggest a quality antenna switcher? the last time i was running anything of quality (ar3500, mid to late 80s) i smoked the one i was using, literally...

i think too i'll leave the swr meter installed in-line once i mess with the install (took me an hour to get the dash back together)...hopefully i can find a nice place to mount the swr, i'm not big on leaving things laying about...clean and discrete for me plz

again, thanx in advance

 

[Superidgit]

Well what you installing this on?

Install options may have an issue with your SWR readings.

Dual whips will have an effect SWR readings.

Your dual whips will need to be balanced. Meaning one needs to be the same as the other.

If you looking for a decent antenna that can take some abuse the wilson 2K is an option.


However running duel 2K's I do not know anything about that. Seen them on the road though.


If you can just hook one antenna with one coax and get swr down to where you are happy then hook up 2nd antenna and get SWR whaere you are happy. Then when you get both inline you should be really close. I would think any how.



A bit more info and maybe I can help. I know the people here on this forum can help they have truckloads more info then I do.

 

[Whiplash-265]

I'll post pics tomorrow of the install

2011 Ram 1500 Quadcab

originally i was using a single wilson 5k, which was giving me the broad sweep with power increases...power down at about 4w the needle barely moved but once you applied power (about 60w) she'd hit around 1.5:1 on 1 and near 3:1 on 40 (recalibrated after power adjustments)
antenna is roof mounted, approximately 6 inches from rear of cab..
started with the factory recommended 1" to start and worked my way up and down the whip with no real improvement

spent the past couple hours ripping apart the truck and have now installed the swr inline and at the same time re-run the coax for my dual stix (previously matched/balanced for prior install) and things are looking much better on those regardless of power setting..the only issue i see here is range as they're mounted just above box level so the entire cab is a hinderance

will find an open area tomorrow and try matching the 5k again, expected more??? I liked it for the power handling abilities, the magnet mount and the removable coil).....maybe i shoulda stuck with my gut and grabbed the K40 lol

thanx again for the comments

 

[Whiplash-265]

pic as promised...hopefully this works

http://dl.dropbox.com/u/25598532/Magnum257hp.jpg

 

[Superidgit]

I am thinking somewhere your antenna isnt properly ground. Thats my first opinion.



There are peeps on this fourom that can smell the problem when people type them.

Any moisture under the Mag? Have you looked under the hood of that coil on that 5K?

?Have you tried just switching to a another antenna?

 

[Superidgit]

Very Nice install BTW!! Very nice!

 

[Whiplash-265]

I am thinking somewhere your antenna isnt properly ground. Thats my first opinion.



There are peeps on this fourom that can smell the problem when people type them.

Any moisture under the Mag? Have you looked under the hood of that coil on that 5K?

?Have you tried just switching to a another antenna?

completely dry in all respects...had the radio in and out prob 4 times over the past couple of days, and it's no easy task especially with the fuse block there, looks nice but man what a PITA to re & re it
i've checked all my grounds (from antenna to frame) and all appears good
also, both radio and antenna were brand new this past friday...coil/whip removed daily for security reasons
i've played some more with match, adjusting for the high-end first and then checking lower output...nothing as bad as original results but still kinda surprised by the differences
the wilson came with a spare solderable connector (original seems a little flimsy) so if it starts to swing again i'll start with that

re-calibrated my twins and results are similar to the wilson

air-flow behind dash is good, not as closed in as it appears to be..so the amp isn't cooking

i will re-visit the link you referred to above and try working my way through it again, 'tis a tad technical for my blue-collar edumication

again, thanx for all your help Superidgit!!

i'll see if i can find the pics of the meat of my install

8ga power wire from battery running thru 200a circuit breaker..
leads to 100a fuse block...Magnum inline fuse still in system

http://dl.dropbox.com/u/25598532/circuitbreaker.jpg

http://dl.dropbox.com/u/25598532/lbrackets.jpg

http://dl.dropbox.com/u/25598532/twins.jpg