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On 29 Sep 2006 09:49:48 -0700, "Telstar Electronics"
wrote in .com: Frank Gilliland wrote: You measured output power with a spectrum analyzer, so why should I believe that you measured harmonic distortion with anything more than a wattmeter? Of course I don't believe you, Brian; you haven't made a single verifiable claim regarding any of your amps. In fact, I can guarantee that your 516 watt PEP figure was never measured but only fabricated (what you call 'estimated', just like you 'estimated' the distortion figures on your previous Class C splatter-boxes). I think everyone here who has read has this entire thread has figured out by now: You have never used a spectrum analyzer Don't know what PEP power is Don't understand how to measure efficiency Don't know how to measure harmonics I can't wait to see your new amplifier... LOL Since you still can't address the issues, once again I will address them for you: The PEP to carrier ratio of 4 to 1 presumes a linear response. The problem is that these transistors (operating above 100 watts PEP; or, more specifically, your "1dB compression point") are not only horribly NON-linear, but you will be pushing them into saturation way before reaching your fabricated figure of 516 watts PEP. Don't believe me? Crank up your amp and try it. Pump in enough carrier to bring the output to 129 watts then modulate at 100%. I doubt it will even reach 400 watts PEP, and I have -no- doubt that the harmonic content will be absolutely horrendous. I also have no doubt that the amp won't last ten seconds under these conditions because the thermal resistance of the heat sink that is required to operate at this power is -0.26 degrees C/W.... and yes, that's a NEGATIVE number which means you need ACTIVE cooling, and a lot of it!!! See what happens when you refuse to do the math? You end up proving that you have don't have the engineering background to build even a -CHEAP- CB amp....."LOL"!!! |
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