Originally Posted by Simbalage22
Is any of this true? And If so why do we put swing kits in our radio's in the first place? I have been searching on what the right deadkey with and without and amp and this just tops the icing on the cake
Wrong. An AM
signal is fully modulated when the "swing" doubles the carrier. That is to reach 100% modulation a 4 watt key should swing no more than 8 watts. Anything more than that is distortion to your voice. The AM
carrier is necessary for the receiver to properly demodulate the audio from the signal. If you add excessive swing it will distort your audio. It will not help you get out better.
That part is partly true,the swing should double the carrier peak voltage,but it quadruples the pep power not doubles it p=v squared/r
ie if peak carrier voltage was 50v then 50v x 50v /50ohms = 50w
if peak voltage is doubled with 100% modulation added,then it becomes 100v x 100v /50ohms = 200w pep
if you want avg of peak power (avg peak power = rms of 100 peak volts squared /50 ohms) then it would be 70.7v (the rms voltage of the 100v peak) x 70.7v /50 ohms = 99.9698w avg peak.which is probably where he got his doubling of power from by using a non powered peak reading meter.
a 4w key should swing approx 15.6w pep for 100% modulation.
whoever wrote that has confused voltage and power.anything over 100% modulation is distorted whether you can hear it or not.
have a look at the bottom pic (a pic is worth a thousand words) in this link you'll see what happens when you overmodulate,the green graph is a spectrum analyser representation,watch as the harmonics either side of the fundamental frequency grow the more you overmodulate: Amplitude Modulation
Keep it clean,sound mean.its not rocket science!!!