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To swing or not to swing

Discussion in 'CB and Export Equipment and Accessories' started by ron103067, Apr 12, 2010.

  1. ron103067

    ron103067 Active Member

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    All I know is that when my radio had the swing kit it was garbage wouldn't be heard over 5 miles with my TS killer bee behind it now that I had the kit removed I have had numerous 10 mile conversations. So that is what I know


     

  2. The Jerk

    The Jerk Active Member

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    This sounds like the amp was being driven to saturation (over driven), and not really the swing kit sounding "bad"?

    Don't get me wrong, I've heard a friend's S9 with 1 watt swinging to "60"; and while they seemed loud up close, they fall off all of a sudden with any distance.
     
  3. Simbalage22

    Simbalage22 Active Member

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    What makes the MOST sense... Forget a scope which in no way can show real performace. I started a thread similar, and 1/4 of avaliable power should be deadkey, and the rest swing. I have tried this method in real life situations and its true.. If the deadkey is say 1 watt and your swinging to 60, sounds good up close, but fades with distance.. Think that lowering deadkey is mainly for amps that require it.. Either way you need decent carrier to get out, and swing to be heard loud and far..


    From my other thread... this makes the MOST sense
     
    #93 Simbalage22, Aug 7, 2010
    Last edited: Aug 7, 2010
  4. Oldtimer

    Oldtimer Active Member

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    I'm so confused with all this back and forth I'll just ask.
    I have a Galaxy 48T DX radio. I have no external amp. What do y'all recommend I set my power to?
    Thanks !!
     
  5. Beetle

    Beetle Sr. Member

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    Full legal limit.
     
    wavrider likes this.
  6. Mustang 131

    Mustang 131 Sr. Member

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    Leave
    Leave your radio stock. If you need more power buy an amp.
     
    tecnicoloco likes this.
  7. Oldtimer

    Oldtimer Active Member

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    My radio is stock. It has two finals and puts out close to 250 watts.
     
  8. Mustang 131

    Mustang 131 Sr. Member

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    Then your done. Very few techs these days can do much more then gay watts.
     
    tecnicoloco likes this.
  9. 9C1Driver

    9C1Driver Sr. Member

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    Your radio has two 2290 finals, same as a Texas Star 250 amplifier. Have your radio tuned and aligned to factory specs and be done. Some one has done some tweeking and tuneing to that radio, 250 watts from two 80 watt finals is quite a bit. Also bone stock that is a 10m radio only so it has been converted at some point if you use it on 11m.
     
  10. Mustang 131

    Mustang 131 Sr. Member

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    It was designed from the factory to work on 11. Actually 10 is for our friends at the FCC. Would any ham ever use that radio on 10??
     
  11. DTB Radio

    DTB Radio Well-Known Member

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    I didn't even bother to read all the replies, just going to add my quick 2 cents. For transfomer-modulated radios, you will generally be limited to the 4:1 ratio, since there's no practical way (that I know of anyway) to add negative peak compression to a transformer-modulated radio. Transistor-modulated radios can be modified for negative peak compression, which will allow for higher modulation levels than 100% without any noticeable distortion, up to about 150%. After that, you run into added distortion. As for the distortion, that appears in two ways. You can visit www.dtbradio.com/amc.html for my further thoughts on that subject.

    One note on the swing or modulator kits that get put into Cobra 29's, etc: With those kits, you will ALWAYS get clipping of the valleys of the AM modulated signal (unless you cut the mic gain so far back that you negate the whole point of the mod), so you will ALWAYS get distortion with those mods. I'm referring to the cap and resistor in parallel.
     
    NZ8N and Shadetree Mechanic like this.
  12. Shadetree Mechanic

    Shadetree Mechanic 808 On The North Side of Dover

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    How much swing is too much? The correct amount of swing from the radio will give 1:4 out of the amplifier. Yes / no?
     
    NZ8N likes this.
  13. Mustang 131

    Mustang 131 Sr. Member

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    A clean 150% will sound gooder then a clean 200%. However they both will have some noticeable distortion on cheap receivers. That's why the commercial stations run 120% max.
    I run around 160% PEAK for non channel 6 tawhk'n.
     
  14. 543_Dallas

    543_Dallas Sr. Member

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    It's best to use an oscilloscope.

    The ratio depends on audio bandwidth, the amount of asymmetry in your voice, headroom and other variables. The 4:1 thing is only accurate if you modulate the carrier with a single tone.

    Some transmitters will not make 100% positive modulation before the negatives hit 100%. In cases like this the 4:1 ratio is over modulated and letting you ignore another issue.

    More than 100% modulation can be done cleanly but you won't get it at the cb shop. 300% modulation sounds perfectly fine on a synchronous receiver.
     
    NZ8N and Shadetree Mechanic like this.

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