yihi and temp control on fancy builds

[mac-nutty]

I've never heard a dna rattle snake and I have the 60, 75, 75c, 200 and 250.

not so much hear but you can feel it on a dna bit a yihi needs more user input before it works

this will lead on to the something else i have found earlier
can i ask what are the time stamps for the graph posted and what boards what tested on the video linked ? Thanks @Punk In Drublic

 

[F-machine]

The orig OP post solved, @mac-nutty ?

Try pressing both up and down buttons when in TC mode, does it show coil reading?

 

[mac-nutty]

The orig OP post solved, @mac-nutty ?

Try pressing both up and down buttons when in TC mode, does it show coil reading?

solved thanks everyone

 

[mac-nutty]

tbh i can see myself travelling through to Edinburgh or fife for advice on a new mod lmao

#define

 

[Punk In Drublic]

this will lead on to the something else i have found earlier
can i ask what are the time stamps for the graph posted and what boards what tested on the video linked ? Thanks @Punk In Drublic

The device in the video is the SX Mini M Class and time of the video was April of 2015.

But the reason of me posting the video was to not compare a 4 year old device, but to demonstrate the rattle snake noise that according to comments made here and elsewhere on da web, is still an occurrence. This was the best video I was able to find that displayed the rattle snake noise.

The video also displays PFM on a scope despite Paul referred it to be PWM. And again, not trying to compare it to other devices. Just a demonstration.

 

[mac-nutty]

The device in the video is the SX Mini M Class and time of the video was April of 2015.

But the reason of me posting the video was to not compare a 4 year old device, but to demonstrate the rattle snake noise that according to comments made here and elsewhere on da web, is still an occurrence. This was the best video I was able to find that displayed the rattle snake noise.

The video also displays PFM on a scope despite Paul referred it to be PWM. And again, not trying to compare it to other devices. Just a demonstration.

pm mate

 

[TrollDragon]

tbh i can see myself travelling through to Edinburgh or fife for advice on a new mod lmao

#define

The Shed laird will give you sound advice for sure!

 

[mac-nutty]

The Shed laird will give you sound advice for sure!

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[mac-nutty]

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[mac-nutty]

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[TrollDragon]

That's too bad... I hate to see discussions go sour, which is why I stay away from the mech/battery threads.

 

[mac-nutty]

)

 

[classwife]

Knock it off in here - members aren't appreciating your antics.

 

[mac-nutty]

agree sorry
i love this forum and its members but i was targeted by """""" and tbh i have not replied till today nothing i said was taking things to far
thanks again for the warning xx

 

[Fidola13]

Clarification….

Given many, including PBusardo and DJLsb, assumed SXMini’s output in PWM, I made the same assumption. They do not output in PWM for Temperature Control, but employs PFM (Pulse Frequency Modulation).

PFM operates in a similar fashion as PWN where the sum of on/off state dictates its output voltage. However, unlike PWM where the on state (Duty Cycle) can vary but at a constant frequency, PFM has a fixed on state interval but increases/decreases the frequency in order to modulate the voltage. As an example, the on state could be fixed at 1 millisecond, but the frequency (how many times) of on state over the duration of 1 second will be greater, for maintaining a constant voltage, or less, for reducing the voltage. Attached is a simple (and poor) diagram displaying the 2.

For those like me who has never heard this rattle snake noise, PBusardo’s took an audio recording of it in action. As Paul describes, if your wicks are wet, the sound is less noticeable for the device is not trying to modulate the voltage. As your wicks dry, the device begins to modulate, and the sound becomes more noticeable. Just to note, PBusardo does state PWM in this video, but his scope clearly indicates a PFM signal. This is not as apparent on DJLsb measurements. Paul does state in a much later video that the SX Mini outputs in PFM

View attachment 814909

The Rattle Snaking sound can be, but not always, common with PWM power sources. Pulse Width Modulation operates by rapidly switching between 0 volts to full voltage similar to a square wave. The duration of full on, vs full off creates an average voltage that is referred to as the Duty Cycle. So as an example, 4 volts with a 75% Duty Cycle will give an average of 3 volts. The rattle snake sound is the regulator switching on/off as per the Duty Cycle which depending on the frequency this may or may not be humanly audible (but measurable). Some PWM designs include hardware filters to suppress this noise, some Class D power amplifiers as a good example.

Not quite sure how Yihi regulates its power within TC. The specs states an output of 0.7 to 9.5 volts for the SX485. This leads me to believe it sets a voltage based on the prescribed Joules and resistance of the coil similar to how a DC to DC regulated device works - then scales back that voltage to control the temperature via PWM by decreasing the Duty Cycle percentage.

Technically by manually changing the resistance you are changing the output, which in turn is changing how the Duty Cycle operates thus moving that audible switching to a frequency that is no longer audible. Quick Google search displays some users having the same effect by adjusting their Joules output.

But one would think that a 0.001 ohms would not make so much of a difference. Interesting!

This makes sense to me. I posted earlier in this thread that once I learned that I needed to adjust the joules I no longer had any throttling.

 

[Fidola13]

@stols001, it's an alternating hissing kind of sound. Not fun when you hear it for the first time and you have no idea what it is.

I was sure my 1st Yihi SX Mini Q Class was either broken or sucked lol!! It took me forever to find the solution by reading hours and hours of posts and watching videos. Now it has a wonderfully smooth vape.

 

[Fidola13]

@madstabber, no worries. I can let you know what I think about it, going to need a cheat sheet for creating charging profiles for different batteries though. If I remember rightly, @Jazzman has had a MC3000 at their disposal for a little while.

And the only thing that I can think of with the 0.001 increase to the resistance seeming to resolve the rattle snaking issue, is it must be something to do with an algorithm in the firmware causing errata with the resistance reading and therefore power regulation.

But, rattle snaking is quite audible. First time you hear it you think that the mods broken or you broke it somehow, it's quite disconcerting.

I actually noticed the effect on the draw more than the noise when I first experienced it.

 

[Fidola13]

I miss everything !

 

[Mordacai]

@Fidola13, true. I even got sound effects.

Dropped an email to YiHi to help clarify things further with the Joules setting yesterday, I now await a response from them.

And yes folks, Samsung 30T do fit the SkyRC MC3000 charger. With a few millimetres wiggle room.

 

[Fidola13]

I contacted Yihi as well at the time. I can’t remember what the response was but it wasn’t helpful.

I actually found a video BY Yihi explaining to joules issue that people were having. I didn’t save it. Or maybe I did I’ll look.