Important Information: Reviewers and Pulse Width Modulation mods

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Sense Field

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Hey guys,

So I've been doing a lot of research and I've found that there is a reason why all the VV devices that use Pulse Width Modulation seem like the are tuned incorrectly. It's because they are! They are tuned to Vave (the average voltage) rather then the Vrms (some technical term that requires real math to calculate). This means if you set it to 3v, you might actually be getting around 4.5v depending on your set up.

So here is what I have learned, and it's important to know that what you've seen in reviews is incorrect (and I am guilty also). Reviewers need to disclose their lack of professional training in electronics because there has been a lot of misinformation spread since we all started using scopes to test these devices. We as a community need to demand that manufactures who use Pulse Width Modulation to achieve VV do it correctly, if they do not, we will call them out.

A new inline meter is available and it's going to make it easy for anyone to find the actual voltage of a device, me and some friends talk about the inline meter and the issue at hand below.

So here we go again guys...here is the video:

 

KuroCz

Senior Member
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Sep 12, 2012
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Nice video, and doesn't really shock me that chinese mods are faic'd, it happens in many industries where there's a known expectation. One thing that I personally don't miss, is when you geeky reviewers (you, fazzed, pbursardo, and I mean that in a appreciative way), say "it feels different". Unquantified, but not overlooked ne. You got suckered, you found out, they've been busted, good job and keep the great reviews coming!

However... your opening statement of "why all the VV devices that use Pulse Width Modulation seem like the are tuned incorrectly.." is technically incorrect yes? (my italics). Not to be nitpicky but since it's all about accuracy ;)
 

Sense Field

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Yeah, the eGo units the Darwin and I believe the Provari use PWM. So not "ALL"...more like "some". But otherwise... great post.

Well, besides the eGo, the scoped wave on those devices doesn't seem to look the same as a Vmax, or some of the other Chinese mods out there.

I should have been more clear, yes, this does not pertain to those mods you listed.
 
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Sense Field

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@sensefield... do you have a zmax on the way that you'll be able to throw the numbers up for? i have one coming in the co-op and i'm VERY sceptical now in the accuracy of that device...

I don't, but maybe I should. I was in wait and see mode because those things are expensive! Haha

Know if anyone selling them cheaper the $120?
 

Butters78

Vaping Master
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Jan 24, 2012
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Sense Field,

You're doing a great service to all us vapers and I can tell you genuinely care about us and want to make sure we are getting the right information. This may rattle the cage a little bit but it's important for us to have the most accurate data we can on our investments.
 

yzer

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Nov 23, 2011
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Glad to see someone step up and admit to what was going on. The ripple effect went far beyond just the PVs as a lot of people using some PWM/VV units couldn't understand why their LR cartos, clearos, etc. were tasting burnt at what they assumed was 3.7V or less.

If Chinese PWM/VV manufacturers respond by making APVs with accurate voltage output how long will it be before these reach the world market?
 

Sense Field

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Glad to see someone step up and admit to what was going on. The ripple effect went far beyond just the PVs as a lot of people using some PWM/VV units couldn't understand why their LR cartos, clearos, etc. were tasting burnt at what they assumed was 3.7V or less.

If Chinese PWM/VV manufacturers respond by making APVs with accurate voltage output how long will it be before these reach the world market?

This could even be why the boge cartos have recently been tasting "weird". They might be getting burnt right off the bat.
 

Rader2146

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Mar 11, 2012
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Correction to the math in the video:

Vrms=SQRT(duty cycle) * Vmax

I don't fault the manufacturers for "inaccurate tuning". In reality, they don't do the tuning...there is nothing for them to tune. The manufacturer of the voltage regulator does the tuning and the regulators are repurposed for an application for which they were never designed for. The cost factor for an ecig manufacturer to "tune" the device would be outrageous to the end user and would require additional components; ie: programmable microprocessor.

What I do fault the manufactures for is poor implementation of the voltage regulator. When you boil it down to the base functions of a device, there is ONE difference between the "accurate" mods and the "inaccurate" mods....a filter that would cost me roughly $2 to make from parts bought online. I'm sure the Chinese could buy bulk for a fraction of that. An LC Filter (inductor and capacitor paired) is the difference between the "inaccurate" vape of a VMax and the "accurate" vape of a Provari.

So realistically, and in the interest of the consumers wallets, what we should be asking for is to implement a filter into these mods, not the more expensive route of trying to "tune" to Vrms.
 
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