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Negative Peak Clipping is easily applied to ANY radio...IF you know what you are doing. Usually it requires two components... both diodes, but they must be selected to work with the particular setup on your radio.

Selecting the components requires a complete understanding of how Amplitude Modulation works, an RF voltmeter, an oscilliscope, and a thorough understanding of basic electronic theory. Unfortunately... from what I've seen over the past 2 years, this eliminates about 90% of the people on this forum.

My RCI 2950 is setup with 22 db of audio clipping using a Uniden speech clipper PCB from a Superscope CB640. The NPC is a 2-diode device of my own design that allows 130% positive modulation peaks while limiting negative modulation peaks to approximately 95%. This results in a signal that is extremely LOUD and CLEAR without generating any harmonics and splatter. BTW... the mod limiter in this radio is not disconnected.
There is no rocket science to this. There are 2 mods: one for direct-coupled modulators, and another for transformer-coupled modulators. The basic theory is the same, but the diode selection process is different.

When my wife (and our digital camera) gets back from the US, I'll post some O'scope pics of my mod and more particulars on how it works. Like they say... a picture is worth a 1000 words.

- 399

<blockquote data-quote="unit_399" data-source="post: 172482" data-attributes="member: 7311">Negative Peak Clipping is easily applied to ANY radio...IF you know what you are doing. Usually it requires two components... both diodes, but they must be selected to work with the particular setup on your radio.&nbsp;Selecting the components requires a complete understanding of how Amplitude Modulation works, an RF voltmeter, an oscilliscope, and a thorough understanding of basic electronic theory. Unfortunately... from what I&#039;ve seen over the past 2 years, this eliminates about 90% of the people on this forum.&nbsp;My RCI 2950 is setup with 22 db of audio clipping using a Uniden speech clipper PCB from a Superscope CB640. The NPC is a 2-diode device of my own design that allows 130% positive modulation peaks while limiting negative modulation peaks to approximately 95%. This results in a signal that is extremely LOUD and CLEAR without generating any harmonics and splatter.&nbsp; BTW... the mod limiter in this radio is not disconnected. There is no rocket science to this. There are 2 mods: one for direct-coupled modulators, and another for transformer-coupled modulators. The basic theory is the same, but the diode selection process is different. &nbsp;When my wife (and our digital camera) gets back from the US, I&#039;ll post some O&#039;scope pics of my mod and more particulars on how it works. Like they say... a picture is worth a 1000 words.&nbsp;- 399</blockquote>

[QUOTE="unit_399, post: 172482, member: 7311"] [B]Negative Peak Clipping[/B] is easily applied to ANY radio...[B][U]IF[/U][/B] you know what you are doing. Usually it requires two components... both diodes, but they must be selected to work with the particular setup on your radio. Selecting the components requires a complete understanding of how Amplitude Modulation works, an RF voltmeter, an oscilliscope, and a thorough understanding of basic electronic theory. Unfortunately... from what I've seen over the past 2 years, this eliminates about 90% of the people on this forum. My RCI 2950 is setup with 22 db of audio clipping using a Uniden speech clipper PCB from a Superscope CB640. The NPC is a 2-diode device of my own design that allows 130% positive modulation peaks while limiting negative modulation peaks to approximately 95%. This results in a signal that is extremely LOUD and CLEAR without generating any harmonics and splatter. BTW... the mod limiter in this radio is [B]not[/B] disconnected. There is no rocket science to this. There are 2 mods: one for direct-coupled modulators, and another for transformer-coupled modulators. The basic theory is the same, but the diode selection process is different. When my wife (and our digital camera) gets back from the US, I'll post some O'scope pics of my mod and more particulars on how it works. Like they say... a picture is worth a 1000 words. - 399 [/QUOTE]

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