Copper Talk » Ask The Tech » Amplifiers » Messenger M250 « Previous Next »

Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Mobilepainter
New member
Username: Mobilepainter

Post Number: 7
Registered: 5-2004
Posted on Monday, June 21, 2004 - 1:39 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I have a Cobra 146gtl that dead keys at 3 watts into a Messenger M250. The power output is fine about 40, 100, 250 or so according to my radioshack meter. My SWR is 1.5 with just the radio, 1.7 with the amp on, dead key. When I talk my SWR increases over 3, is this normal? I realize the amp isn't exactly high quality but will this have any ill effects on my radio?

I run a wilson 1000 on a 91 honda civic, not much of a ground plane. I have been considering a groundplane kit for it. I have read it a waste of money but I have also read it "may" lower my SWR and increase my RX range a bit.

Don't grief me but........ I bought my coax from radioshack. The packaging said it was all 50ohm. 18' section from my amp to my antenna and a 2' section from my radio to my amp, RG58.

So what are my options? Completely redo all my coax with Belden RG8?

An antenna tuner inline after my amp?

And/or a low pass filter inline after my amp?

And a side note. spitting out a bunch of numbers in regards to ohm loads and antenna impedence or whatnot will go right over my head. I drive a truck for cryin' out loud, keep it simple for me please =)

I also only run the amp on low, about 40 watts.

Mobilepainter AKA Lagwagon ch8 & 17 NW Washington.

Top of pagePrevious messageNext messageBottom of page Link to this message

Tech8541
Moderator
Username: Tech8541

Post Number: 224
Registered: 12-2003
Posted on Wednesday, June 23, 2004 - 12:10 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

here is exactly what you need to do;

turn radio on...turn amp on...talk. your system is fine. don't worry about the swr when you talk, whistle, or whatever.

your not running 1000's of watts so r.shack coax will work fine. not the best in the world, but you will never be able to tell the difference if you did change it out. cb freqs are too low.

Add Your Message Here
Post:
Username: Posting Information:
This is a private posting area. Only registered users and moderators may post messages here.
Password:
Options: Enable HTML code in message
Automatically activate URLs in message
Action: