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what NPC/RC mod looks like on a scope

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Top Gun Tech shows similar scope patterns with the CP-1 compressor and MD-1 modulator modules "on" - right pic.
Are these circuits accomplishing the same thing by different means?
Picture on the left is compression/modulator "off' .
Comment CBDoctor?
 

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I don't see ANYTHING that is being done that will inhance the signal. The best that I can see, there is no positive peak inhancement. It is apparant that the negative peak is somewhat compressed due to it's brightness but it does no good to compress the negative peak while still limiting the positive peak and that is what the pattern seems to show.

73's :laugh:
 
Hello Bill,
I have been promoting and using your npc/rc mod for a real long time. I have been going back to your old site(I-40 exit 220) forever looking to see if its got new info. For the heck of it today I was searching the mod and google lead me here.
By the way that site is in bad working order LOL!! Its good to hear you will be having a new one.
I thought you fell off the face of the earth, I am happy to have found and met you. Thanks for the npc/rc mod!!! Its been great!!! I have had it for a decade or so maybe more, where do the years go LOL! I need to get this mod into my 2995DX now. Let us know the address to the site as soon as its done.
Thanks Again!!! Kerry AKA Lost Ram.
 
Rob, that looks like classic 100% modulation where the peak voltage is twice that of the unmodulated carrier.

Look at this site about 1/2 way down, starting figure 6

http://www.icycolors.com/nu9n/scope_your_audio.html

I'm still waiting for the pudding. We'll see if the proof is there. I'll be surprised if the key measurements are even shown, much less set up correctly.
 
OK, Rob. Maybe you copied the wrong image.

npc.gif
 
It always seemed to me, that if you start with a double sideband, unsuppressed carrier, and want to eliminate part of one sideband and suppress part of the carrier to increase overall output, there's a much easier and efficient way of going about it. It's not a new idea, it's been around for a while. Care to guess what I'm talking about?
- 'Doc

What happened Doc? Everyone is afraid to guess!

Let me see, does it include filtering? And, something else...hmmm
 
There is absolutely NO corelation between SSB and NPC-RC. The NPC-RC modification If NOT meant to supress the carrier which is done in SSB. It is also NOT meant to get rid of one of the sidebands such as is also done in SSB.

In An SSB transmitter, the sidebands are generated by a balanced modulator for the purpose of totally suppressing the carrier. Then one of the mirror-image sidebands is filtered out completely leaving the other sideband which has all of the information needed to detect the intelligence off of the sideband with a product detector at the receiving end.

The NPC-RC, on the other hand is meant to inhance an AM signal and does NOTHING for an SSB signal. There are literally THOUSANDS of communications hobbist that prefer talking on AM to talking on SSB. Also SSB is totally impractical for use by a truck driver to keep communications with his or her fellow drivers on the road. No truck driver is going to reach out and fine-tune his radio to bring in an SSB signal. If truck drivers did use SSB, most of their day would be spent fine-tuning his radio and he would just get frustrated and throw his radio out of the window.

NPC-RC does not SUPPRESS the carrier--IT COMPRESSES THE NEGATIVE PART OF THE CARRIER.

More later--I keep falling asleep while trying to write this. I have to go to bed.(y)
 
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And you still haven't addressed my last comments on this topic. I'm always looking to learn, so educate me. And then tell us why we should get so excited over the fact that this mod is nothing more than the basic negative clipper circuit that I posted a diagram of which has been around forever.
 
.

NPC-RC does not SUPPRESS the carrier--IT COMPRESSES THE NEGATIVE PART OF THE CARRIER.

WRONG!

Inorder for this type of modification to provide a performance increase, it is necessary to compress/clip/limit the NEGATIVE MODULATION PEAKS, not the carrier. Positive peaks should be between 120 - 130 %, and negative peaks should be limited to about 95 %, or supressed to just about the level of the carrier. This is the classis AM Broadcast station setup that produces increases loudness without generating harmonics and splatter.

Moleculo is right in that this mod you're promoting is nothing new.

- 399
 
You might as well just cut the goddamn limiter if you want this crap---same results. How many Cbers that are going to want this crap are going to have a scope, or any clue as to where to set the mic gain? Everything is going to be cranked wide open before long, so you might as well just rip it out entirely, same difference.
 
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You might as well just cut the goddamn limiter if you want this crap---same results.

Why do you suppose the AM broadcast stations do it? Do you think they just want to make there CB listening audience happy? :LOL:

As has already been said, this IS nothing new, it has been in use for many,many years. The whole issue is proper setup, and utilization.
 
Guys stop giving CB doc a hard time. He did a basic peak and tune on a Cobra 148 GTL for me a few weeks ago and showed me 80 watts from a stock final radio on his meter. No mosfets,no mod kit,no npc mod. Just a stock 148,WOW 80 watts!!!!

If he can show me 80 watts on his meter from a stone STOCK finaled 148 then you boys know this man has his shot together!

......and let me tell you about the Connex 3300 HP that i got from him that same day with the NPC/RC mod. My local cb tech fell out of his chair when he saw all that had been changed inside the radio!
 
80 watts from a stock cobra 148 ? really ?
howdidhedodat ??????
 
Id like to see a video of that 148 (80watts) posted on here, and pictures of the inside of the Radio? What say u post some huh? Look forward to seeing it. Thank u.
 
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