1. You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.
    Dismiss Notice

Adjusting SWR with amp

Discussion in 'CB Antennas' started by T-bone, Nov 28, 2007.

  1. stevejrfan

    stevejrfan Member

    Joined:
    Oct 9, 2017
    Messages:
    11
    Likes Received:
    3
    Ok guys ive got some swr problems with the meter and amp inline i have very high swr ive hooked only the antenna up and less than 1.5 soon as i put it back on meter there high again i took meter out of line hooked to amp then radio and is high but just antenna by itself there fine any help would be appreciated thanks


     

  2. 338_MtRushmore

    338_MtRushmore Sr. Member

    Joined:
    Jun 17, 2012
    Messages:
    1,238
    Likes Received:
    699
    Sounds like a bad jumper, if I deciphered correctly.
     
    Shadetree Mechanic likes this.
  3. stevejrfan

    stevejrfan Member

    Joined:
    Oct 9, 2017
    Messages:
    11
    Likes Received:
    3
    Replaced jumpers also guess i should have added that sorry
     
  4. stevejrfan

    stevejrfan Member

    Joined:
    Oct 9, 2017
    Messages:
    11
    Likes Received:
    3
    I think its something to do when i hook up the amp inline i ran just the radio and meter and everything is fine under 1.5 what could cause the amp to make the very dangeroulsy high not even running it or turning it on
     
  5. RT431

    RT431 In the swamp

    Joined:
    Dec 2, 2018
    Messages:
    488
    Likes Received:
    790
    How long are your jumpers?
    Try different jumper lengths.
     
  6. stevejrfan

    stevejrfan Member

    Joined:
    Oct 9, 2017
    Messages:
    11
    Likes Received:
    3
    Ive done 3ft 6ft jumpers still no change in swr it just happened couple days ago was working fine till then with the 6 ft jumpers
     
  7. RT431

    RT431 In the swamp

    Joined:
    Dec 2, 2018
    Messages:
    488
    Likes Received:
    790
    Check all PL connectors with a vom, they might look ok but a meter will tell the story. Also, check any and all grounds.
     
  8. dave457

    dave457 Sr. Member

    Joined:
    Jan 3, 2009
    Messages:
    842
    Likes Received:
    880
    Could be the amp itself is not tuned correctly
     
    Shadetree Mechanic likes this.
  9. stevejrfan

    stevejrfan Member

    Joined:
    Oct 9, 2017
    Messages:
    11
    Likes Received:
    3
    Tryed everything i know to do the swr is good with just the radio and meter checked the pl connectors and cleaned soon as hook amp back inline swr go out the roof could be in the connector part of the amp or maybe internal guess its time to take to the cb shop get it checked out thanks guys
     
  10. BammBamm

    BammBamm Instigators ...173 on the southside.

    Joined:
    May 24, 2010
    Messages:
    604
    Likes Received:
    216
    Have a similar issue myself. My swr shows 1.3 on each end of the 40 channels with amp off but when it’s on it drops to 1.0 - 1.1
     
  11. Bionic Chicken

    Bionic Chicken Active Member

    Joined:
    Jun 6, 2008
    Messages:
    392
    Likes Received:
    28
    Put the SWR meter in place of the amplifier and check/set SWR. Once you have it set then reinstall amp. If SWR goes up with the amp inline (but not turned on) some internal tuning to the amp will need to be done. Changing jumper lengths does not do anything but fool the meter.
    You can put the SWR meter in between the radio and amp...then key the amp, calibrate the meter, and check the amps input SWR. If the input of the amp is tuned correctly it should be low.
     
    DXman, hotrod and The DB like this.
  12. Handy Andy

    Handy Andy Do Your Research First, Then Decide...

    Joined:
    Apr 23, 2018
    Messages:
    2,324
    Likes Received:
    2,276
    Whoa, slow down.

    I'm with Bionic chicken (Hey guy Wazzup?) here, better to find the Amp is causing the SWR being in line and something is wrong with it's network - either in Bypass or when in line - something is not right.

    A 1.5 SWR with no amp in line may be fine. But if you got a radio that is putting 52MHz into that antenna - OR - you have an AMP that is putting in 52MHz harmonics in that antenna - that 1.5 SWR with the radio ONLY shows me one of two things.

    Retune that radio to drive the amp properly.

    Amp and antenna are not getting along.

    Swapping jumpers is not the game here, you have some retuning of amp or radio OR BOTH - ahead of you.

    Don't got for max wattage - best to go for the cleaner power - everything else you're trying to put thru and show on a meter is just that - wasted watts with a LOT OF HEAT and high-SWR problems with BIG TIME $$$ consequences if you don't fix this soon.
     
    DXman, Slowmover and The DB like this.
  13. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

    Joined:
    Oct 23, 2017
    Messages:
    2,549
    Likes Received:
    2,865
  14. OldTech03

    OldTech03 Sr. Member

    Joined:
    Dec 15, 2017
    Messages:
    577
    Likes Received:
    881
    Try some silly things if you have not already.
    Hook the amp up but don't supply any power to it, in other words, leave the power cord unconnected and check swr and while you are doing this take note to make sure you can't hear a difference on the radios background noise or see a difference in noise level on the meter as well as take note to where the power meter on the radio is when you key the mic with no amp in line and with respect to where it reads when the amp is in line.

    I didn' notice anywhere in the text that you even tried to key the amp through all this I assume you have not because of the high SWR. You may try to quickly key the amp for just as long as it takes you to key the mic another words like less than a second would be more than enough while you put your ear on the amp case to see if you hear any relays clicking. as a matter of fact, you should listen to the amp the same way when you do hook power up to the amp to see if you hear any clicking when hooking power up to the amp But be sure all the switches in the front are off position.

    There if all that isn't confusing enough give me a while I'm sure I can make it more confusing.
     
  15. Tallman

    Tallman W9WDX Amateur Radio Member, KW4YJ EXTRA class

    Joined:
    May 1, 2013
    Messages:
    4,543
    Likes Received:
    4,439
    What type of amplifier do you have?
     

: vswr

Share This Page

  • About Us

    The WorldwideDX Radio Forum was originally established in 2001. We pride ourselves on welcoming Radio Hobby enthusiasts of all types, while offering unbiased, informative, and friendly discussion among the members. We are working every day to make sure our community is the best Radio Hobbyist's site.
  • Like us on Facebook

  • Premium VIP Member

    The management works very hard to make sure the community is running the best software, best designs, and all the other bells and whistles. Care to buy us a beer? We'd really appreciate it!

    Donate to us!