To swing or not to swing  | | 
04-12-2010, 08:18 PM
| | Senior Member | | Join Date: Dec 2008
Posts: 189
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Quote:
Originally Posted by JoeDirt View Post
Now matter what your not going to get over a 100% modulation with any swing kit!
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Originally Posted by slprydk  I have been a tech for over 30 years, this statement is just not true... Quote:
Originally Posted by JoeDirt View Post
Just because your scope shows its more than a 100% with a swing kit does not mean its true.
| The only way to check the % of modulation after installing a swing kit is with a scope simply because you can't calibrate a modulation meter with your RF power fluctuating all over the place. | If you set your swingkit up for asymmetrical modulation your carrier increases with your mod, so your never going to really get over a 100% CLEAN MOD. You can always run more than a %100 but you negatives are going to be at zero volts creating distortion.
And yes mod meter suck at telling your the correct % of mod, but on a scope when your looking at a radio with a swingkit the carrier increases with the modulation so your scope lies to you too. The only way to show what you modulation is really doing with a swing kit you need a demodulator in conjunction with your scope.
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04-12-2010, 08:31 PM
|  | Yup | | Join Date: Dec 2008 Location: Silicon Valley CA, Storm Lake IA
Posts: 6,894
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Quote:
Originally Posted by Highlander_821 I strongly disagree.
Just because a mosfet CAN do this, does not mean that it sounds good. Robb and his locals appear to think that they sound good this way. I think they sound terrible, raspy, crunchy, badly overmodulated.
A radio that uses mosfets can be tuned to just swing at a 1:4 ratio. That is how they should be set up. Anything more not only sounds crappy, but it trashes the band, making it harder for others to use.
I'm not saying that they aren't "loud", I'm am saying that they sound bad. | Funny; I never ask others when talking skip some 9,000 miles away in New Zealand how my radio sound. Yet they always give me flowers w/o asking. Happens all of the time. They don't know about these dumb arguments and bickering, they just hear me and I hear them. Simple.
Oh; are you referring to that video with the mic I reviewed? The guy who shot that video had his radio up too high. I thought you knew that already? I use my OmegaForce every day and wouldn't trade it for another.
Sounds Fantastic! 
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BASE: Kenwood TS-2000 w/Alpha Delta DX-CC, Diamond X50A, Sirio SY27-4, and IMAX 2000.
MOBILE: Galaxy DX99V w/RF Limited CR-577 mic, Sirio Z-180. Yaesu FT-8800R & Diamond NR-770.
"...2 WR-011..."
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04-12-2010, 11:58 PM
| | | | Join Date: Apr 2002
Posts: 7,844
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I don't like the way a radio sounds that has a huge carrier to peak ratio, either. It's loud as hell, but it doesn't sound good to me. I realize that a lot of people like it, though.
Robb, I assume that your New Zealand example was using SSB, not AM? The carrier/peak ration discussion is moot on SSB, although over modulation is still an issue.
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04-13-2010, 12:01 AM
| | | | Join Date: Apr 2002
Posts: 7,844
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Quote:
Originally Posted by JoeDirt If you set your swingkit up for asymmetrical modulation your carrier increases with your mod, so your never going to really get over a 100% CLEAN MOD. You can always run more than a %100 but you negatives are going to be at zero volts creating distortion.
And yes mod meter suck at telling your the correct % of mod, but on a scope when your looking at a radio with a swingkit the carrier increases with the modulation so your scope lies to you too. The only way to show what you modulation is really doing with a swing kit you need a demodulator in conjunction with your scope. | Not exactly, and we've been through this before. Study some of the material here for a more detailed discussion: Oscilloscope Monitoring | eSSB | SSB | AM Audio Modulation, Amplifier and System Linearity
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04-13-2010, 12:16 AM
| | Yup | | Join Date: Dec 2008 Location: Silicon Valley CA, Storm Lake IA
Posts: 6,894
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Quote:
Originally Posted by moleculo
Robb, I assume that your New Zealand example was using SSB, not AM? The carrier/peak ration discussion is moot on SSB, although over modulation is still an issue. | Yes - SSB...
Not an issue with anybody that I talk to regardless if they are ten miles away or several thousand.
Never has been either.
It's just a rehash of the same old jive.
__________________
BASE: Kenwood TS-2000 w/Alpha Delta DX-CC, Diamond X50A, Sirio SY27-4, and IMAX 2000.
MOBILE: Galaxy DX99V w/RF Limited CR-577 mic, Sirio Z-180. Yaesu FT-8800R & Diamond NR-770.
"...2 WR-011..."
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04-13-2010, 01:17 AM
| | Senior Member | | Join Date: Oct 2006
Posts: 787
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O.K. Hereʻs a gate of me on 43WR137 photobucket video log. Right around the 50 sec. mark. Im running a President Grant w/NPC-RC (diode-resistor)mod, running stock microphone, and my Black Widow 350 @ 240+ watts.
Radio DK is 2+ watts swinging 22+ pep. I think it sounds kinda muffled due to the stock mic Im using. If it was maybe a power mic(D104/575/Road Devil) then it might have sounded different.
Heres 1 with the same setup (mic/radio/amp) but on SSB!!! it right around the 21:18 mark. Justin.tv - CA. USA - Recorded live Apr 11 2010 at 8:19PM GMT
I will try to get a different gate when I get my turner +3 mobile mic and see if it makes a difference in audio etc.
Aloha, Jim.
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Mobile:
Prez Grant Export/Stock Mic
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Two 9" Predator 10K
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Base:
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04-13-2010, 02:53 AM
|  | Amour d'Ecosse | | Join Date: Apr 2005 Location: Central IL
Posts: 1,417
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Quote:
Originally Posted by Robb Funny; I never ask others when talking skip some 9,000 miles away in New Zealand how my radio sound. Yet they always give me flowers w/o asking. Happens all of the time. They don't know about these dumb arguments and bickering, they just hear me and I hear them. Simple.
Oh; are you referring to that video with the mic I reviewed? The guy who shot that video had his radio up too high. I thought you knew that already? I use my OmegaForce every day and wouldn't trade it for another.
Sounds Fantastic! | Sorry, but the guy's volume on his radio had NOTHING to do with your crappy sounding radio.
And the fact that you get "flowers" all the time only means that there are lots of other people out there that are just as ignorant as you.
Once again, I am not saying that 1 watt swinging 30 isn't "loud." I am saying that it sounds like crap. I am overjoyed to know that you use your radio everyday and love it. Doesn't change the fact that it sounds like crap.
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N9RZF, David on Ham Bands.
Yaesu FT-847, Galaxy DX-2517, President Lincoln, Cobra 150 GTL, Uniden Grant LT.
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04-13-2010, 03:34 PM
| | Member | | Join Date: Aug 2009
Posts: 43
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Quote: |
If you set your swingkit up for asymmetrical modulation
| IF, the word speaks for itself... Do you use a scope, an RMS reading meter, or a Peak reading meter to accomplish this one? Quote: |
If you set your swingkit up for asymmetrical modulation your carrier increases with your mod, so your never going to really get over a 100% CLEAN MOD. You can always run more than a %100 but you negatives are going to be at zero volts creating distortion.
| Yes, when the negatives hit zero distortion starts because you are at 100% modulation regardless of what the positive peaks are doing. Think of it this way, when your negatives hit bottom and stay there for any length of time it is the same thing as your positive peaks flat topping, it is distortion in either case because, positive or negative peak, you have reached the electrical limit of your amplifier. This means your positive peaks can swing to high heaven but if the negatives hit zero you are at or over 100%. You can see this in just about any 29LTD with a swing kit and the diode clipped, well if you look at it on a scope that is… Quote: |
on a scope when your looking at a radio with a swingkit the carrier increases with the modulation so your scope lies to you too.
| The negatives still tell the tale regardless of what the positive peaks are doing.
Your talking about a swing kit, and for the most part this means a resistor and a capacitor in parallel, there's no magic here. These two parts installed as a swing kit do nothing to prevent your radio from going over 100% modulation. If your radio can sound distorted and go over 100% without the swing kit, its going to do the same thing or worse with the swing kit.
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