JAC Vapour Series-B DNA75, reading wrong resistance (bit too high)

[DMcC]

Have been experiencing some oddities with reading resistance on a DNA75 (in a JAC Vapour Series B DNA75).  Note that I'm thrilled with this device generally speaking, and have been quite pleased with the Evolv boards given my experience with other mods, but have encountered some issues with my TC which I'm trying to resolve.

Being highly specific: for MTL purposes, I made a coil from Lightning Vapes SS316L Clapton wire (28/36); 6 wraps, 2.5mm.  Steam Engine suggests this should be around 0.7ohm (give or take, leg length and all that), and indeed when built and installed in a Kayfun Prime, tested on my Coilmaster tab it reads at 0.71ohm...so far so good. 

When I put this on my Therion 166 (I realize this is a DNA250-based board), it seems to correctly read it at 0.71 ohm and seems to work pretty flawlessly for TC with wattage set to 25W (which again is as I would expect given my experience with the wire---drops to around 13-15W once at temp) so seems like all is well.  When I put the same tank on the Series-B, it reads it at 0.77ohm and the TC gets odd which is to be expected I guess since the chip thinks the cold resistance is 0.06ohm higher than it actually is---with the same 25W it never thinks it hits 220C so I'm basically just using the coil fired at 25W mode (and temperature is likely higher than 220 once it gets going I'd assume based on what's going on when it's on the Therion).

I've done a lot of reading about this sort of thing now and realize I should ensure a few things are set up properly, and am in the process of doing just that.  From the mod settings in EScribe, I can see that there isn't really any manufacturer set-up going on here as the case resistance is set to 0...all values appear to be stock default (the Therion came with case resistance set to 0.004).  The atomizer analyzer isn't showing any drift in the resistance while it's sitting there (other than minuscule fluctuations as it quick-fires the SS coil), and I did a case analyzer run as the room temperature display was whacked anyway and I've allowed EScribe to set that up for me for what that's worth so will see if that helps at all.  Am working on doing the "short" test to see what the case resistance actually is and will set it accordingly once I have the numbers---am waiting for a friend with some solder to come by so I can do the soldered-510-atomizer approach.

My concern is that given that case resistances tend to be below 0.01, this isn't likely to be effecting the resistance reading sufficiently to account for the 0.06 difference I'm experiencing with this coil (although is likely having a more dramatic effect on the 0.15 Ni200 stock coils I use in their S22 tank so definitely worth doing regardless).

I'm asking then what the next step should be should the above not correct this issue.  My current plan is next to open the device up, ensuring connections/threads are clean and verifying that all the screws are making good contact with the board/510/etc.

Just seeing if there is additional input as I continue to work on this issue as given my inexperience, this is proving to be very time consuming as it is

Thanks

~DMcC

[JAC]

I have seen one other device reading high, and when we got it back, it looked like there was an issue with the connector, it was sticking slightly and the user had been using the Beserker tank on it, which is right at the limit of the spring in the 510, over time it started to cause the connector to stick a bit, sometimes it would jam in, and cause odd readings. I am sure people will have more insights here, but if you continue to have issues, and can't get it sorted, we can replace the device for you if it is a fault in the device. The case resistance is 0.003, and I have a file for setup which was produced by one of our testers if you want that setup to see if it helps. I've attached it. It was done for using a 25R

Jacsetup.ecig

[DMcC]

I didn't expect the good JAC CS to extend here as well...  well played.

Thanks for the setup file, appreciate that.  Had already set a case resistance of 0.004; however, I'll take your setup over my poorly calculated one any day.  Interesting information about the pin and the Berserker Mini as I do use 2 of those tanks so entirely possible it's related.  And with you having mentioned it, just looking at the pin on the Berserker as compared to the Kayfun I see exactly what you're referring to - that is a long pin.  Never noticed that before.

For clarification, is this pin sticking something evident with the pin itself, or something under the pin that is getting jammed?  I tested the pin just now and it seems to be springing just fine at least externally; however, since you mentioned the Berserker, I tossed one of those on multiple mods for testing as well and indeed am getting higher resistance reading on those as well.  I wondered about the Ni200 coil in the S22 tank and tested that one as well - my ohm meter shows it as 0.14 ohm, but the device is reporting 0.15 (my knowledge of electronics at this level is limited so perhaps this is a similar misreading for the lower ohms?)

I'd prefer not to replace it if at all possible as I live overseas and would be quite put off not having my favourite mod during the exchange so will continue to poke at it a bit for the moment.  If the issue does turn out to be the pin though, would replacing the device fix the issue as I would expect they all have the same parts.

Definitely will thank you again for popping in with the ecig setup and additional information.  Really appreciate it.  Can't tell you how much I like this mod...pry it from my cold dead hands kind of thing :).   If you guys do decide to move to a DNA75C-based build, you can just shut up and take my money now.

Will update the device using your setup and case resistance, and will continue to explore this minor issue for now and will update.

~DMcC

Edit...oh, I was attaching a JAC Vapour welcome screen I made for the mod as it came with the stock Evolv config and didn't have one, and I guess I'm a bit OCD about such things, but noticed that (naturally) there is one in the provided profile :).  Now, do I like yours better, or mine...hmmm...   And I didn't make a secondary screen.  Such a scrub.

Edited March 9, 2018 by DMcC

[JAC]

I actually can't take credit for the setup, we ran a test group on POTV forum and a couple of the users came back with tweaks and adjustments to the setup, so that's effectively the file I sent. The unit I saw that came back to us, the pin was fully sticking in, and this seemed to be causing the issue, it was more prominent at about a 0.2 variation, and it did change. I have tested units of ours against other devices, and there always seems to be a very slight variation between boards, I have not however tested it against another DNA 75 device, I have another 75 board setup in a very basic device and get pretty much identical readings on both with the same tank, so it may be a thing with the 75 board. I have a 75C  board here as well, but that's not in a full function device at present, will be going into our next device in a few months, but I can't compare at present, but I will run a few tests with my device against and ohm reader and various builds to see if  its similar to yours

There will be more knowledgeable people here that can possibly shed some light on the matter, so hopefully somebody will chime in. I only just joined as your thread popped up in a search and I didn't want to leave you hanging, and thanks for the good comments about the device, is it the Sandstorm version you have? or the black? 

[DMcC]

Ah, well I appreciate the file regardless.  I compared it to the case analysis that I had run yesterday and most of the thermal properties were within "wiggle room" of about the same so I just used the ones in the provided file.  And good to know it was a physically jammed pin you're referring to - that definitely isn't the case here.  The pin is still moving just fine and at least at this point isn't giving any sticking issues with the Berserker or otherwise but I'll keep it in mind for future reference.

I did wonder if it was a DNA75 chipset thing, as this is the only DNA75-based product I own and I can't rule that out yet either.  I still feel like just having a once over with the internals to ensure good contacts and tight screws isn't amiss.  I've seen so many other reports of misread resistance being related to a slightly loose ground screw and the like to not check that.

The one I grabbed is the black one (22mm) for reference.  I just adore the finish on it and am a big fan of 22mm tanks anyway so it was the perfect choice (although I am tempted to grab a sandstone one as well which would let me use my Siren 2 more easily...maybe another one for my wife as well...  yeah, it's a sickness but I'm just thrilled with that device, what can I say).

Interesting to hear JAC is maybe going to do a DNA75C mod though.  Last I heard it wasn't clear there was demand for it, but should a "Series-C" (or whatever it should be called) appear with the DNA75C, I'll be ordering the same day, foreign exchange and overseas shipping be-damned.  To have something so compact, Evolv-based, and then with "replay" functionality on top of that...  good lord that would be christmas.

Thanks again for the feedback and we'll see how this goes.  Cheers o/

~DMcC

[JAC]

So I've checked various units here, and I am getting the same reading on all DNA 75 units, but my ohm meter is not reliable (I am getting fluctuation on that), to be honest I have not used it in a while as I just test stuff on the DNA, my builds are never very accurate anyway, as I am kack at building. I've ordered a new ohm meter so that I can run tests and be sure of accuracy. Let me know how you get on, and if you find a solution or if there is anything you want me to check at this end.

I think the new replay feature sealed the decision for us on the 75c, The prototype will be finished next week, so assuming all goes well, I'd think we'll have it out by August, I can't really say any more than that at present. There will be a dual 18650 and a 21700/18650 version, the 21700 version is actually currently smaller than the current SERIES B DNA 75, but that many change slightly after we've finished the prototype.

[DMcC]

Hard to imagine a 21700 version smaller than the existing Series-B...that battery has 3mm on the 18650; however, as long the aim is "compact" I'm sure all will be well on that one however it turns out.  And no need to say more about JAC's plans.  Am excited enough to hear there is are 75C models coming  so thanks for sharing that :).

~DMcC

[DMcC]

And by way of update...

I have disassembled the mod at this point and there are no screws as it turns out...everything appears to be soldered (and well I might add) to the appropriate connections on the board and 510 plate.  A friend has suggested I could go over the board with a magnifier to look for any weak or damaged printed circuits and the like; however, that is getting a little extreme given what's happening here.  I guess I could try desoldering the existing connections and resoldering them in case the issue is with a connection being made there; however, that is a bit more effort than I'm willing to expend under the circumstances.

Where I've come to now, barring any suggestions that might come from others, is that the mod is just reading the resistance a bit on the high side for whatever reason (whether a general DNA75 thing, or whatever).  Because it is so constantly reading high---no variation at all, I'm just adjusting my temperature settings to compensate as it still works just brilliantly, it's just reading the resistance a bit on the high side and I've got used to the appropriate temperature settings to get the vape I'm after at this point.

Would still be interested if anyone has additional input as I'd love to correct it if possible.  Otherwise, am just going to vape on here and look forward to the DNA75C models when they become available.

~DMcC

[JAC]

okay I've tested 5 units here and they all read the same, starting with a cold tank, I get the same reading on all devices, and it matches our new metre, I've also got the 521 coilmaster and it reads identical to the DNA 75, also got the coilmaster mini and it reads 0.01 difference higher. I am testing with a 1.0ohm nichrome coil, and it reads 1.07 on all but the mini that reads it as 1.08. So I'm not seeing anything unusual here, so the variation seems to be particular to your unit. If you find that you can't live with that variation, then I am happy to get it replaced for you.

[Wayneo]

@DMcC Here's my suggestion/thought. Can you build a kanthal coil on another atty, and test it on your Therion and Jac using Atomizer Analyzer or Device Monitor. Both of those display that third decimal point, whereas your mod will round up or down for display. 

[JAC]

Okay thanks Wayne,  I built a 0.9ohm Kanthal coil, ohm meter is 0.89, coil master is 0.90, DNA 75 device is 0.91 and Device monitor is 0.901 cold and 0.912 live

[DMcC]

Indeed, thanks for the input.  It will be a day or two before I have an atomizer free to do this specific test; however, I do have Kanthol coils in a Pulse 24 RDA at the moment (although the resistance is lower, so the misreading is scaled down), and just tossing them on readers I get:

Tab: 0.23    Therion: 0.23   JAC: 0.25

Note that's a squonking RDA in mid-use so I'm not leaving it on there for too long to minimize the juice I have to clean from the connector when I remove it :).  So although I don't have the atomizer analysis numbers yet (and will do that with a higher resistance kanthal build just to make any discrepancies more apparent), the essential numbers match my experience thus far.  The DNA in the JAC just reads it a bit high (my Ni200 coil: Actual: 0.14, JAC: 0.15; the SS316L: Actual: 0.71, JAC: 0.76,; Kanthal: Actual: 0.23, JAC: 0.25, etc.).  Everything I've tried just with the simple "read the ohms" produces exactly the same general effect.  The JAC reads them high, by some percentage I'm guessing as the higher the actual resistance, the more pronounced the misreading of the resistance.

As I said though, this is not exactly what you asked for, just confirming the trend of high resistance reading on a kanthal build rather than SS316L.  I'll be due to recoil one atomizer within a day or two and will do a build with 24 gauge kanthal and record the data you've mentioned and update.

~DMcC

[Wayneo]

Without a proper copper tool, many of us have validated the below, and although initially written for the 250 board, the link in the comment will show the validation with the copper on a 75.

Read this 1 comment by giz https://goo.gl/m8zrFH    and follow the link in there
Then
Wire picture (March 10 post) https://goo.gl/3BSsMV
Takes a few minutes, and it should be correct for YOUR mods.
IMHO, acceptable values would be in the .002-.009 range. Note the double zeroes.

OR

Ideally an AA Printscreen (shows 3 digits) from each mod with same Kanthal or non TC wire/coil and RDA, and what I'm asking can wait.

Is the Therion a BF?

What is the current mod res of each? 

[JAC]

It will be interesting to see how the rounding is effecting things, if the therion is reading 0.234, and our one is reading 0.245 that's a 0.011 variation showing as 0.2 between the mods. The higher coil is above these sort of rounding issues though, so if you could build something in the 0.8-0.9 range we can see if this is consistently off and with the greater margin. The mods I have here are all within Waynes range and explained by decimal rounding.  It seems odd it would increase with the higher coils, if it was consistently off by a fixed amount, you could just adjust your internal resistance and it would read fine, but a percentage adjustment isn't possible.

[DMcC]

Ok, let's see what I've managed to do (or do wrong as the case may be)...

I made a coil from 24gu kanthal which my tab was reading as 0.98ohm on a freshly cleaned Siren 2 deck.  I changed the mod resistances to 0 for reference (previously the Therion 166 was factory set at 0.004ohm, the JAC was set to 0.003 by me based on the feedback provided).

Therion 166: mod display: 0.96; Analyzer showing: 0.960 cold, 0.984 reading (varying 0.979-0.987 over time while analyzer running) - 1st screenshot below

JAC DN75: mod display: 0.99; Analyzer showing: 0.995cold, 1.022 reading (varying 1.017-1.027 over time while analyzer running) - 2nd screenshot below

---

Also did the same test setup using the small wire suggestion--a small arch of the same 24 guage kanthal---in the link (which I assume is to actually better calculate mod resistance).  The tab was reading it as 0.31ohm with the following results:

Therion 166: mod display 0.31; Analyzer showing 0.306cold, 0.313 reading (varying 0.308-0.315 over time while analyzer running) - 3rd screenshot below

JAC DNA75: mod display: .33; Analyzer showing 0.331cold, 0.333 reading (varying 0.330-0.335 over time while analyzer running) - 4th screenshot below

If I'm interpreting this correctly, the 0.003 case resistance on the JAC seems about right.  The 0.004 the Therion was set to looks about right as well (might be 0.001 or 0.002 low, but it's close in any case).

---

As for the original query, you can see again why I get confused by that as the JAC is showing a 0.02-0.03+ difference in the base reading of the coil (and short wire).  The Therion is a 166 as I mentioned, not a BF (and I realize that means it's a DNA250-based board in that one...just trying to get my head around the difference in readings on the two devices as I do move the tanks around).

Not sure if this is revealing or not, but tried to gather the data

~DMcC

(edited to label the screenshots)

Therion 166 - 0.98 kanthal:

JAC DNA75 - 0.98 kanthal:

--

Therion 166 - short wire kanthal

JAC DNA75 - short wire kanthal:

Edited March 17, 2018 by DMcC

[Wayneo]

The 1st portion of my last post (apparently poorly described) was an alternate method to check/set the mod internal resistance. Usually done with a TC wire, and I never tried that with Kanthal.

The portion following the OR was meant to look for rounding errors with the mod and atty combinations in their then current state with a non TC capable wire.

A .01 or .02 reading in reality is close enough for Rock and Roll. You could raise the Therion internal resistance up by .001 to see if that helps.

I am of the belief that running your own Thermals and setting your own internal resistance is the best thing you could have done, on all your DNA's.

So to be consise. Put the JAC back to its setting. Put the Therion back to its setting raising it by .001 at a time to see if that helps to get them in sync. 

PS. Didn't your Jac read the .15 Nickel as .15(and in what state)? What did the Therion read?

Off topic - Are the thermals done for the Therion, or only the case resistance?

 

Edited March 18, 2018 by Wayneo

[DMcC]

Ah, ok :).  I was also thinking I was covering your earlier post suggesting using a kanthal build with a spare atomizer, which I guess I was as that's the rounding for display issue I believe.  And I now get the first set of instructions too, and why I would have expected to use a TC wire.  I will repeat that but with SS316 and in TC mode next time I change a coil in a tank and won't follow up here as I get what I'm looking for now (and that I'm using the difference to set the case resistance assuming it's a sane value for that).  Apologies for getting confused.

I took your further advice here and ran thermals on the Therion as well as I can tell by looking at the settings that they were still set to the default (only thing that had been set was the case resistance which I think is about right anyway).  So ultimately that's going to be thermals and mod resistance calculated on the device itself for both mods which is great.

The 0.15 Nickel was showing as 0.15 on the Therion, 0.16 on the JAC, and I'm well aware that could be a third decimal place rounding error.  The "wrong resistance" reading seems to only seem significant at higher resistances.  A 0.15 coil seems to read around 0.15 +/- 0.01, however the 0.73 will read 0.77, and even the Kanthal 0.98 was reading as 1.03 in the results I posted earlier.

In the end though, I think after all this testing I've become convinced that your second comment above is the right one for me in this case --- 0.03 resistance off (for whatever reason) is close enough, rock and roll.  I am just having to compensate the temp a bit if it's reading off sufficiently to allow the coil to heat up too much (as I can totally taste it going nasty even though the mod doesn't think the coil has hit temp and just fires it at the set max wattage forever).

I really do appreciate the input that both you and JAC provided as I explored this issue.  I actually understand my devices much better than I did initially which is super-helpful for me and will help as I carry on marching with these DNA boards (and JAC mods) I've become so fond of.  Looking forward to a 75C device :).  I'll continue to test and refine the device settings as best as I can to minimize the difference between them.

Cheers o/

~DMcC

[JAC]

okay great, sounds like you are sorted, obviously the device carries a 6 month warranty, so if things change you know where to find me. I'd also like to say thanks to Wayne for all his input here.

[Wayneo]

9 hours ago, DMcC said:

So ultimately that's going to be thermals and mod resistance calculated on the device itself for both mods which is great

You sound like you've read up on this, or done it (Thermals), but just to be sure ... start with your batteries 25-50% full, and an area with a somewhat stable known temperature. 

9 hours ago, DMcC said:

I am just having to compensate the temp a bit if it's reading off sufficiently to allow the coil to heat up too much (as I can totally taste it going nasty even though the mod doesn't think the coil has hit temp and just fires it at the set max wattage forever).

Are you sure it's being recognised as a TC wire? You could adjust your Preheat watts setting to 30 watts or higher, lower your power (watts)  value to the max you'd vape it normally without nastiness (on this mod). Even if you set it to 75 preheat watts, preheat punch 11, and preheat time limit to 10 seconds (all ridiculously high), the mod will revert (drop) to the regular 'Settings', power value if it does not see a quick enough rise in resistance.

[DMcC]

Yes, had to delay doing the thermals a day on the Therion  to get the batteries in the right range.  I just do it on my desk which is stable enough I think.  Room temperature and all that.

I understand what you're saying about the pre-heat; however, my experience with that particular wire when the resistance is read "correctly", tends to have it cut back to 13-15W once at temperature (maybe trending lower if the wire is already quite warm from chain vaping).  When the resistance reads high, I watch it fire to 25W and just stay there, while reporting the temperature around 180C (while set for 220) and just keeps firing at 25W (and the vape tastes clearly "burnt" and nasty).  It's visibly in TC mode, reporting temperature and the display showing it is still on the SS curve I have for that particular wire (which I obtained from Steam Engine for the particular clapton wire being used).

I don''t go for a higher preheat due to the burnt taste to begin with - in said situation it's clearly not seeing a resistance it would consider 220C which I'm attributing to it reading the cold resistance high to begin with (perhaps incorrectly, but it seems to fit).  Starting it up at 30W rather than 25 may well get the device thinking it's hitting 220, but given it already tasted nasty with it firing the 25W constantly it seems like this would be worse.

I've wondered if it was possibly a side-effect of mounting the coil badly or something; however, thus why I mentioned I put the exact same tank/coil on the Therion and it reads the resistance closer to what the tab was saying, and fires it as I'd expect with wattage set to 25W (which effectively is the pre-heat I figured, as it cuts back to 13-15W once at temp anyway.  And tastes fine.  This also suggests it's not the atomizer (which in this case is a Kayfun Prime) having odd resistance, as again it reads and fires fine on other mods (and I did ensure the 510 pin was good and tight as I'm aware there have been some strange TC with a pin that seems to be shipped a bit loose on that tank).

As I think was mentioned earlier, I could just set the case resistance on the JAC to 0.02 or something and it would correct the behaviour (and it does actually for the 0.72ohm coil)); but then I'm concerned what a setting like that would do when I use the 0.15ohm stock coil Ni200 for which that 0.02 is a much higher relative difference from the actual resistance of the wire.

I'm going to try some other variations in setup to see how this behaves under different resistances.  I built a vanilla 26ga 316L coil for my Siren 2, which comes out more like 0.6ohm with 8 wraps, and I'm finding the performance to be quite good (was not sure how low I can let the cold resistance go with SS316L and still get decent TC results...seems 0.6 is fine...I read somewhere that higher is better for SS).  Will try that on the JAC next time I rebuild the Kayfun and see if I notice any difference in run-time behaviour.

Either way, it's not that big a deal at this point as the solution with the "reads high" 0.7ish coil has just been to set the temp to 170C and it seems fine that way.  Hopefully the 26ga coil I try next (which being 2.5mm rather than the 3.0 I can fit in the Siren will be 0.55ish I'm guessing) is still high enough to give good resistance readings for TC.

I appreciate that JAC will replace it under warranty if I want, but it's not like the device is failing, or even behaving differently over time - it's easy enough to just drop the temp setting and rock and roll and I really do love that little mod.  I don't want to be without it :).  If I order another one before the 75Cs drop, maybe I can then do an exchange if absolutely necessary (but who am I kidding...from my cold dead hands I tell you!).

Was hoping when I started this thread to see if there was something I was overlooking, or doing wrong, that I could correct.  At this point, barring there being some impurities in the solder used for the wiring effecting the resistance, it seems to just want to read a bit high.   If I get adventurous one day, I might try resoldering the connections to see if it's that.

~DMcC

[JAC]

No problem with your idea of ordering another one and comparing then returning the old one, if that's the route you decide to take the option is there.

[DMcC]

You won't be getting this mod back (even if I do order another) :).  The "issue" is too minor to interfere with my enjoyment of the device, and is more about just seeking some vision of perfection that may or may not actually exist.  Appreciate how flexible you guys are about this sort of thing---although, my experience with JAC customer service has actually been outstanding so not entirely surprising you're on the same wavelength.  This is part of why I'll just be ordering any 75C-based mods you might put out sight unseen.  Great company.

~DMcC

[DMcC]

AND...perhaps I've spoken too soon and the board (or some connection) is actually failing here and I've been tooling around like there is a minor fix but it's actually getting worse.

Was finding the TC this morning to be rediculously weak, and sure enough it was clearly dropping wattage to 2W or so once it fired so it think the coil is at temp really, really early.  I'd taken to locking the ohms when I put the tanks on to ensure it didn't do any drifting, but in this case I flipped over to wattage mode to see whether it was the resistance again (which was working just fine in wattage mode otherwise...but of course, it's just dumping 20W on the coil in this case which was still vaping ok, just not temp controlled).

But lo and behold it's now reading a 0.74 coil as 0.83 or 0.84 when stone cold...tried different tanks/coils and same thing - it's reading resistance so high now that temp control is effectively broken unless I compensate and turn the temp up to 250 or something (verifying each of those tanks on the Therion to ensure it's not the tank/coil shorting or something else that's odd -- tested the Kayfun tank, 2 different Berzerker Minis, a Berzerker MTA RDA and the JAC S22 tank with various coils for reference).  Series-B is now reading a JAC 0.15ohm Ni200 S-coil as 0.20 (again, the magnitude of the "off reading" is somewhat proportional to the resistance as noted earlier, but you get the idea).

Will proceed now under the assumption something is actually up with the board or something similar and will contact JAC CS to see about getting it replaced :(.  Going to really miss that mod while I deal with this.

~DMcC

[JAC]

I dropped around CS this morning and explained the issue and they'll send you out a replacement, you can then compare the 2 units and make sure your happy going forward.

[DMcC]

Heh.  I beat you to it and ordered another one on the weekend anyway (not specifically to replace this unit, as I've decided to go ahead and get one for my wife as well) so a sandstorm model should be shipping to me today I think.  Am dealing with the CS side as well so it will get sorted in the end.

Sounds like you're still waiting on new stock of the black one anyway so timing should be excellent for this and will allow me to continue to use the device in power mode for a week or so which seems to still work fine (ignoring the resistance display --- found another tank/coil to try this morning and it's reading my 0.60ohm vanilla SS316L coil at 0.70ohm cold so the misreading is definitely persistent and seemingly increasing).

 Thanks again for your feedback and flexibility while I've struggled with this issue.  Now I'll have 2 of these in the family...and still will buy the DNA75C model when it shows up.  Man, I have issues, or that mod is just so central to my enjoyment of the day...which is also a sign of madness, surely.

Oh - unrelated: Berzerker MTL RDA...man, I'm enjoying that dripper.  Will be lovely having my TC back as I drip on that and am not the most attentive person with respect to letting the wick dry out a bit

~DMcC