any modulation meters that go above 100%?

[fireball894]

Hey slim jim, I run a gen lee myself in the mobile, with an Astatic 636L mic, and with the mike gain wide open, I bet its in the ballpark of 100%. 10w swinging 40 and clear LOUD audio. I remember the first time my wife had the truck and keyed it up while I had the base on, I couldnt believe how good it sounded. LOUD LOUD LOUD but no crunchy fuzzy sound...............

[lonesome 500]

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

i give you facts.....there is no...none....nada wiggle room.....fact is fact....electrical principal

perfect wave form is 100 percent carrier insertion.....no more

there is no other way to look at it........it is making your meter lie.....

buy an oscilloscope.....learn how audio is added to carrier signal

[Slim Jim]

Hey slim jim, I run a gen lee myself in the mobile, with an Astatic 636L mic, and with the mike gain wide open, I bet its in the ballpark of 100%. 10w swinging 40 and clear LOUD audio. I remember the first time my wife had the truck and keyed it up while I had the base on, I couldnt believe how good it sounded. LOUD LOUD LOUD but no crunchy fuzzy sound...............

O yeah! That'd be the last radio I'd ever get rid of. Mine will go over 100% mod a little bit, especially if you yell into the mic or something, but I try not to crank it up on purpose. I've never had a bad audio report on that baby and the way I normally leave it setup is around 2-3 o'clock on the mic gain. Of course, it'll be different on other radios, but that seems to work for this one.

[ww228kidd]

example
i will throw this out for you guys to figure out.lol.... on an adverge power reading Bird 43...key 16,000 backswing to 11,000... skipping talking from NC to TX....then the man says dang scooby you are loud...i ask, how many pounds you got on me crack carter.. his reply is, key again you hand me locked let me turn my RF gain down some...i key again with the same power as before....crack comes back and says, you have the carolinas on hold and you are all by yourself , 5 swinging 9......

another example....
stock mic with mic gain turned all the way up...key on a peak meter (Dosey) 3 watts swing about 25 watts....put a hand held D104 on the radio...3 watts swing 35 watts....check modulation on stock mic and the reading is just a hair past 100% then check with the D104 the reading is 120%...
called a base station 20 miles away...put the stock mic back in and ask how it sounds...response was sounds good ....change mic to D104....called base once again...response was sounds loader and crisper, what kind of radio you talking on...

not gonna say anything else, you guys just explain...

[dud muck]

I'll give it a try...

Bird 43 backswinging from 16,000 to 11,000: bird 43 is only accurate with a signal without any amplitude modulation, unless it has the peak kit installed, the AM will try to vibrate the needle at the audio rate.
I'll guess the reason the other station hears good forward swing from you is because you're not driving the bjesus out of your amp, and you have plenty of "headroom" to modulate cleanly.

And with the D104 giving 120% modulation... sounding "louder & crisper" is a function of the microphone, and then your RF amplifier stages not being driven into non-linear gain compression. If your amplifier is pushed past its power capability, then you will start splattering and sounding like garbage. But if you amp has enough headroom, then you can modulate past 100% without trouble.

An audio purist would say not to run past 100% modulation, that way your audio waveform would be reproduced accurately at the receiver. But thats not being as loud as you can be. Nothing wrong with your sideband power being push past that which is required for 100% modulation, as long as your RF amp stages have the headroom to carry it.

[fireball894]

Something else to chew on.........................

Exactly how do you figure the receiver at the other end is going to demodulate the audio that is over 100%?

[BtyMONSTER]

so a bird43 without the peak kit is only good for measuring dead key watts on am and not modulated/swing watts ? can it measure modulated ssb watts with out the kit ?

[ww228kidd]

hey bootymonster , i am strickly CB..(Crappy Band).lol....no SSB here..lol.... :D

[209 first class]

ok, im not comparing anything to a perfect waveform,or an oscilliscope. same principal on a guitar amp, just because the wave form is clipped does not mean it does not get louder. a 25 watt rms guitar amp will do maybe 40 watts distorted. the rms measurement is for an undistorted signal. its apples and oranges but the theory is similar. your scope will tell you the relationship of the modulation to the carrier, not the volume of audio above 100%. i have had many meters, i know how they read with many stock unclipped cb's. someone said i may have been talking under 100% the whole time.i doubt it, i know the sound by ear when it goes above 100%. my main radio has a switch to go from stock to clipped in an instant, i love both sounds, i use both. i see the meter after the amp on both all the time. stock radio: 300w swings 800-1000/1200. clipped same radio: 300w swings 1600/1800w.the radio (rci2990) is also internally adjustable for modulation. i can tell the modj meter is accurate because it starts to pop or distort as soon as it goes over 100%. put a switch on yer diode too and check it out. if you have not actually done this, you are speculating. i am speaking fact of my experience. another gentleman asked how the radio could demodulate the distorted signal. i dont have technical answer but if u take a nice tape deck and microphone and put it in front of the receiving speaker it will prove it gets louder if u dont believe the signal meter. 209

[209 first class]

yes, that is true booty, it only reads rms without the kit. you need the kit to see the sideband swing. 209

[dud muck]

Something else to chew on.........................

Exactly how do you figure the receiver at the other end is going to demodulate the audio that is over 100%?

There are two possible behaviors of AM transmitters that over-modulate.
The page here: [Please login or register to view this link]

shows a waveform for two different type of AM modulators. One of them cuts off the carrier at > 100% modulation, and this causes great distortion. The other modulator (four quadrant) shows "negative" modulation with > 100% modulation, in this case it doesn't distort but instead starts becoming like SSB.

I have no idea which type most CB radios are.

[fireball894]

Thats a good link. Actually, it perfectly explains what I and a few others have been trying to say.

But in either method, you are causing distortion to the waveform, and defeating the purpose. When you create this distortion, you are effectively adding noise to your signal beyond 100% MOD.

Like I've said before, carrier and PEP have to be done in balance for it to be effective and sound good. Wanna swing 200? Go for a 50W carrier and you'll be kickin butt. Anything much less, your adding distortion to your signal. That station you are trying to chat with 60 mi away has enough noise trying to listen to you, adding more is defeating what you are trying to do.

I try to make my station sound as top notch as I can, and be as effective as I can. I've heard it at a distance, and I like the way it sounds, especially compared to a few of the locals that mistake their mic gain for an amplifier. When it really comes down to it, if you cant cut it with what you have at 100% audio, you need more REAL power, aka amplifier........ not more audio........

Thats really all I have to say about the topic. I'm sure someone will make up their own radio theory and try to argue, but keep in mind that AM really is old technology, all of this has been known rf theory for decades and decades and decades know........... and still proves true anytine you fire up an oscilliscope.

And as far as audible reports........... youd be surprised how many people hear added distortion to a signal and actually think its louder..............

Scopes dont lie..........

and im back quiet......................

[ww228kidd]

i will still keep putting that maul on them pip squeak sounding radios......sounding like a dang tweedy bird screaming for help when this big ol 120% modulated maul is killing them...lol...as long as my stuff ain't making the man's needle swing backwards on the other end and they say that i am sounding good....run the dang thang, put that hammer on them mudducks that want to keep the original sound....

Mr World Wide Scoobydoo in the Carolinas just got down!!!