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Exactly!
And that's why the "Tall-Ship" AM'ers use a modulator that is at least as powerful as the rig's input power. You need that extra modulation headrooom to gain any benefit from the 3-diode negative peak clipper. And this is why all broadcast transmitters follow the same rule. My BC rigs run a pair of 4-400's modulated by another pair. Those rigs can do 125% positive easy, (if not way more). But, we do the peak streatching upstream in the audio with an Orban, or a Dorrough processor.

I run a 3-diode negative peak clipper (or "negative cycle loading") in my 813 rig: a pair of 813's modulated by a pair of 810's. 700+W of audio modulating 700W of carrier. I get about 135% positive peaks out of that rig. Unfortunately, there are artifacts generated by this circuit, which some listeners find unpleasant. You can't get something for nothing. :sad:

<blockquote data-quote="VA3ES" data-source="post: 254516" data-attributes="member: 15532">Exactly!And that&#039;s why the&nbsp; &quot;Tall-Ship&quot; AM&#039;ers use a modulator that is at least as powerful as the rig&#039;s&nbsp; input power.&nbsp;&nbsp; You need that extra modulation headrooom to gain any benefit from the 3-diode negative peak clipper.&nbsp; &nbsp; And this is why all broadcast transmitters follow the same rule. My BC rigs run a pair of 4-400&#039;s&nbsp; modulated by another pair.&nbsp;&nbsp; Those rigs&nbsp; can do 125% positive easy, (if not way more). But, we do the peak streatching upstream in the audio&nbsp; with an Orban, or a Dorrough processor.I run a&nbsp; 3-diode negative peak clipper (or &quot;negative cycle loading&quot;) in my&nbsp; 813 rig:&nbsp; a pair of 813&#039;s modulated by a pair of 810&#039;s.&nbsp; 700+W&nbsp; of audio modulating 700W of carrier.&nbsp; I get about 135% positive peaks out of that rig.&nbsp;&nbsp; Unfortunately, there are artifacts generated by this circuit, which some listeners find unpleasant.&nbsp;&nbsp; You can&#039;t get something for nothing.&nbsp;&nbsp; :sad:</blockquote>

[QUOTE="VA3ES, post: 254516, member: 15532"] Exactly! And that's why the "Tall-Ship" AM'ers use a modulator that is at least as powerful as the rig's input power. You need that extra modulation headrooom to gain any benefit from the 3-diode negative peak clipper. And this is why all broadcast transmitters follow the same rule. My BC rigs run a pair of 4-400's modulated by another pair. Those rigs can do 125% positive easy, (if not way more). But, we do the peak streatching upstream in the audio with an Orban, or a Dorrough processor. I run a 3-diode negative peak clipper (or "negative cycle loading") in my 813 rig: a pair of 813's modulated by a pair of 810's. 700+W of audio modulating 700W of carrier. I get about 135% positive peaks out of that rig. Unfortunately, there are artifacts generated by this circuit, which some listeners find unpleasant. You can't get something for nothing. :sad: [/QUOTE]

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