any modulation meters that go above 100%?

[209 first class]

it looks like the next line on the meter scale(which is actually the set line) is about 200% on my meter. im sure most of have no problem pinning it. i dont think they would be commercially available, since over 100% is not allowed on the airwaves.. i thought maybe someone may have seen one, or have an idea of how to recalibrate one to read higher. a 400% meter would be nice to see more of whats going on, like at what percentage intelligibility starts to seriously suffer on different radios. 209

[fireball894]

They stop at 100% because there really isnt any more than 100%, anything more is distortion.

[BtyMONSTER]

not saying 209 doesn't care about distortion , but many don't as evidenced by the popularity of 1x4 and 2x4 amps . some would bragg about pegging a 1000 percent meter and swear its as clean as can be .

[209 first class]

yes, i know it is distortion. but, there is headroom, and it gets louder when it goes over 100%.it also puts out more wattage. thats why people clip their radios. there is a certain point on each radio where it ceases to become louder and put out more wattage, and becomes more compressed and less easy to understand. if a radio did not do anything over 100% then people wouldent waste time and money having them modified :D . each station is his or her own judge of how they want the station to sound, and how much distortion is acceptable. some people listen to james taylor, some listen to jimi hendrix. 209

[BtyMONSTER]

very true 209 . people hear differently and some are more sensitive to certain frequencies and harmonics than others . sometimes distortion can sound good AKA the jimmi hendrix reference sometimes it can sound horrible like a cheap car stereo cranked all the way up .

[lonesome 500]

sorry but that is false.....

1. all modulation meters will read over 100%.....move the set point back to a lower mark...most cheap ones go to 130..yeah right....but can be set at the 100% and read to 160

2...MOST IMPORTANT....there is NO headroom. ... there is NO such thing as a 150% modulated carrier insertion.....100% is the maximum for a a carrier that makes a transmitter perform correctly on a given frequency....

all ''radios'' are set to lower than 100% carrier insertion to maintain tolerances...avoid electrical breakdown

carrier distortion has nothing to do with the human ear....it has to do with adjacent frequencies....harmonic frequencies....and neighbors


you can't be 175% pregnant....or have 125% of "a" pie

PS...if you need more 'wattage'.....get a bigger amp........can't squeeze a gallon from a quart

[BigBopper]

my Dosy 4002psw shows more than 100% mod

[BtyMONSTER]

"100% is the maximum for a a carrier that makes a transmitter perform correctly on a given frequency."
"PERFORM CORRECTLY" being the key words there ..... i agree to a point , but some of us aren't gonna let a Lil thing like doing something correctly stand in our way .
different people do have different tolerances and ideas of whats acceptable and apparently that's what is right for them .
i like a Lil echo but some will think I'm an idiot for liking it...............well..................who am i kidding.........some probably think I'm an idiot anyhow but that's beside the point .

[lonesome 500]

...........and still yet...people wonder why cb'ers get a bad name........................

[dud muck]

what you guys are talking about is covered here..
[Please login or register to view this link]

read it carefully.

it says, at 100% modulation: "3) The RMS energy in each sideband would be 1/4 of the carrier level."

So whats interesting is if you could have RMS energy in each sideband that was, say 1/2 of the carrier level, would it be 200% modulation?
I think according to that page, it would be 150% modulation. Its a bit of a brain twister.
Another interesting thought is if you could modulate in that fashion without distortion, would you be louder?

[fireball894]

You simply cannot modulate in that fashion, now before someone talks about backward swing, that is usually someone oversaturating an amp.......

You CANNOT have more than 100%, there is NOTHING louder, just more distortion.........it DOES NOT give you more power...... it distorts the waveform of the signal and increases harmonics.......

If you want to make enemies with your neighbors, and be like half of the people on ch6 that you can only understand about half of what they are saying, then by all means try to run the mythical "200%" modulation. In this case, 100% IS 100%, there is no more.

I prefer to have kick butt, loud, clear audio rather than unintelligble distorted crap. Clarity and loudness go hand and hand when you are trying to talk in the distance, and overmodulating does nothing but actually make you harder to understand. Why would you want to add noise to your signal?

[Johnny Relay]

You simply cannot modulate in that fashion, now before someone talks about backward swing, that is usually someone oversaturating an amp.......

You CANNOT have more than 100%, there is NOTHING louder, just more distortion.........it DOES NOT give you more power...... it distorts the waveform of the signal and increases harmonics.......

If you want to make enemies with your neighbors, and be like half of the people on ch6 that you can only understand about half of what they are saying, then by all means try to run the mythical "200%" modulation. In this case, 100% IS 100%, there is no more.

I prefer to have kick butt, loud, clear audio rather than unintelligble distorted crap. Clarity and loudness go hand and hand when you are trying to talk in the distance, and overmodulating does nothing but actually make you harder to understand. Why would you want to add noise to your signal?

I would hate to try and put a percentage on the number of radio's out there that are running over modulated! I hear them ALL the time. (But I can't understand them)

Anyone wanna jump in and throw a percentage number of what they think are over modulated radios? Compared to the Clean & Loud Radios?

[209 first class]

thats fine if you do not wish to believe going over 100% makes it louder? if there was no such thing as 150% modj, i wouldent be able to pin the modj meter. yes i know it adds harmonics, and that it makes the chance of coming over your neighboors stuff greater, thats all radio 101. my rci 2990 has a switch between the clipped diode so i can go from crystal clear(no distortion) to clipped distorted audio (i like both). the wattmeter swings WAY HIGHER with it clipped. the people 30 miles away i talk local with can barely hear me with the stock radio, but clipped, they can hear me. (this is without an amp). wether its harmonics or noise or distortion , it gets louder . people all the time clip radios and the wattage goes up. if you dont like the sound, you cant deny the facts. 209

[fireball894]

That is like saying you can put more water in a glass if you overfill it..... 100% is a full glass......you cant add anymore without it spilling. Just as your harmonics and bandwidth are spilling over.....

I'm not trying to be argumentative, but the fact is you cant have more than 100%. Anymore is distortion. Try set the thing so its running at 100% peak. Sure , it might go a little over once in a while if you get too close to the mike, but if you set it to where youre slamming the edge of the red line beyond 100% constantly when you talk, youre not improving anything. PEP should be about 4X the carrier.

[fireball894]

Wait a minute.... why would you clip a 2990? Shouldnt you be able to overmodulate it by simply turning up the mike gain, and/or reducing the carrier? There are a few around here, with d104s, and they drive the crap out of a 2990.

[BtyMONSTER]

this is CB fireball894 , if you're getting 300-400 watts per 2879 why not clip some diodes too . besides , every one knows they put extra unneeded parts in radios to keep the factory employees from getting bored .

[lonesome 500]

thats fine if you do not wish to believe going over 100% makes it louder? if there was no such thing as 150% modj, i wouldent be able to pin the modj meter. yes i know it adds harmonics, and that it makes the chance of coming over your neighboors stuff greater, thats all radio 101. my rci 2990 has a switch between the clipped diode so i can go from crystal clear(no distortion) to clipped distorted audio (i like both). the wattmeter swings WAY HIGHER with it clipped. the people 30 miles away i talk local with can barely hear me with the stock radio, but clipped, they can hear me. (this is without an amp). wether its harmonics or noise or distortion , it gets louder . people all the time clip radios and the wattage goes up. if you dont like the sound, you cant deny the facts. 209

good grief........

[BtyMONSTER]

if you cant go over 100 percent modulation then what is over modulation

[dud muck]

100% modulation means that each sideband has 1/4 the power of the carrier.

Nothing prevents each sideband from being more than 1/4 the power, it could be 1/2 or the same power.
It just means that if sidebands are lower than 1/4 the carrier power, then its less than 100% modulation.
It just means that if sidebands are higher than 1/4 the carrier power, then its more than 100% modulation.

You could also maintain the same sideband power while reducing the carrier and then you would be "overmodulated".

[209 first class]

good grief? i thought thats why this forum was here, to debate and rationalise and find the facts and proof if possible. it was very nice of you to throw in an offhanded comment, but it would have been nicer to throw in some speculation with some logical bearing toward the subject or somthing you observed to the contrary. i think the other fine gentleman who are in disagreement may have thier judgement swayed by the fact that wattmeters read and show harmonics and distortions as well as the energy transmitted at the desired frequency. in other words, your meter may show 1000 watts, but only 900w (just an estimate, i dont want to start another disagreement) is being transmitted on your particular channel, the rest is upper harmonics well above the channel your trying to broadcast on.(and yes it is true this is what travels to your neighboors tv.). the final punch line to this one is that the meter on the RECEIVING radio shows higher numbers with modulation over 100%. lots more. got a modj meter ? know a station who can give you accurate meter readings many miles away? try it out. dont forget to ask the difference in loudness from the speaker as well as the meter readings. 209

[J-570]

I'm with 209 on this one, I don't know the technical terms and such but 209 is dead on as to what happens.

And fireball you can't compare a water glass, a physical element to RF or electrical energy.

[Circuit Breaker]

yes, i know it is distortion. but, there is headroom, and it gets louder when it goes over 100%.it also puts out more wattage. thats why people clip their radios.

Um, no...no there isn't. First, people clip the limiters to allow more power, yes. This doesn't necessarily mean they're going past 100% modulation. And, going past 100% does NOT produce more power. If you were to watch the signal on an oscilloscope, you'd see that anything past 100% flat tops...meaning no more power is being produced. All you're doing is saturating the PA and distorting your signal.

[fireball894]

j570.....

Yes, you can compare the two. And also, you can compare a physical element to rf and waveforms, pick up a high school physics book and there will most likely be a chapter on it........

209...
If you are turning your audio up and still getting louder without sounding nasty, chances are you werent at 100% yet to begin with........ it sounds to me like you are going from well under 100% to way over, and thinking anything you are seeing is from going over. As far as you seeing a couple more watts, remember that you have to multiply output power by 4 to see 1 s unit, so carity is just as important as loudness. Ive had guys in the distance figure out that i was far off, and they crank up their mike because they think it helps, when all it does is make it harder for me to hear them through the noise. Set it for where you are the loudest but still have good clarity, and forget it.

[Slim Jim]

I can understand both sides to an extent. I tend to have a bad taste in my mouth for radios that are wayyy over modulated, however. Really, there is no sense in it. Just crank the power up a tad and back the mic gain down just enough to where it doesn't peg way past the 100% mod on the meter. If being over-modulated was such a good thing, then why would any respectable technician out there pay good money for an oscilloscope? Maybe I'm missing something, but I can't stand it when I can here a guy 20 miles away from me putting a nice steady stream of static across all 40 channels when he talks. Most of the locals have had to get filters installed in there radios and I'm exploring my alternatives, as well. No sense in stirring that kind of trouble. I like a nice, loud radio and I'm sure my general lee and others are not under 100% modulation, but I do try to keep tabs on it and I'll back it down when things start pegging the meter. Really a matter of respect. Plenty of people out there don't have any and I don't want to be another like that.

[Slim Jim]

Hey!!! I just realized I have the option to "edit" my posts! Yesssss! anyway...lol