DMcC

Personally, I wasn't expecting much action early in the year in any case due to Lunar New Year. Shame to hear it's been pushed further out but will continue to watch for action. In the meantime, I'm ordering another Series-B as I really do like that mod a lot (and JAC seem to be shipping them with free S22 tanks atm...bonus to snag another one of those) so would be nice to have a spare to fill the void until you get a DNA75C option happening :). Honestly, I could content myself with the DNA75 for most things if it weren't for the relatively poor efficiency of that board (you can rally notice the battery life difference on the DNA75C vs 75). After experimenting I've found I still prefer straight TC over Replay most of the time anyway, and the Series-B is a sexy mod, so what the hell. Thanks for the update again though - always appreciated. ~DMcC

Thanks again for updating. Appreciate that you do that. This is wonderful news, and I understand that there are business issues as well with respect to release dates. I'll keep calm and vape on in the meantime and will still be looking forward to the fruits of all your labour here :). Cheers o/

Heh. The JAC Series-B DNA75 is still a sexy little thing. My sandstorm model has been going strong since I got it and no complaints.

I second the notion that I'd rather wait and ensure quality as anxious as I am for these to arrive. Will continue to look forward to these, whenever they show up :). ~DMcC

Hi Tanny, Nice to see someone poking at this longer than I did...I was going to get into the connections and board more deeply, but JAC convinced me just to do a warranty return so I stopped thinking about it much. Your summary here is amazing and I'll be keeping this in mind should a similar problem arise in future as I still have two of these mods, although both have been behaving well since dealing with the first one I had referenced originally here. As for the DNA75C, I'm still checking my e-mail and their website all the time waiting for an announcement "coming soon" or some such :). They did indicate maybe August, so might be soon depending on how their prototyping and manufacture arrangements are going. I finally got a squonker that uses a 75C chip and holy hell am I enjoying that chip a lot. Amazing board. Can't wait for the JAC update as I'll happily buy an upgrade to the Series-B assuming it maintains that sexy compact form factor which I like so much. Obviously, I do not work for JAC Vapour so what I'm say here about shipping is just based on my reading of their shipping information, but they definitely ship internationally (I live in Canada and they ship here without issue). I don't see any reason they wouldn't ship to India unless there is something about the routing of mail from the UK to India that I don't know about. Cheers and thanks again for posting the solution you came up with here. Very much appreciate it. Keep calm and vape on o/ ~DMcC

Hi again Wayneo. I'm aware the material has to be unused in the profiles. With the new device, the buttons in EScribe are functional, and if pressed would tell me that it's in use by a profile. On the other device the buttons are just greyed out and can't be pushed regardless. I'm not dwelling on that in particular btw, just struck me as a bit odd ~DMcC

Well, the sandstorm model arrived today and while it took me a while to get it all into the setup I was used to with the 22mm one (and I'm having to wait to discharge a battery to 25-50% to run case thermals, and will attempt Wayne's suggested case resistance measurement---but correctly using TC wire this time), it seems to be off and running. An interesting aside (unclear if this is indicative of something off with the board or not): with the new one, I can remove materials from the board. I am unable to do that with the 22mm for whatever reason. I can add materials it seems, but not remove them which always seemed odd to me. For the record, even with the existing case thermals and a case resistance of 0.003, it was reading the resistance correctly immediately. Did some changing tanks while doing set-up and it briefly read a 0.74ohm coil at 0.77 (which could be due to some warmth still in that coil), it quickly settled back to reading it perfectly at 0.74. Meanwhile, the 22mm one is behaving much as it was when I started this thread --- it was back to reading a bit high (~0.77) but still usable, but is already slowly creeping up over time and is 0.79 currently on that same coil so I'm going to assume nothing was fixed in a persistent manner from my jiggery pokery and as you say, there is possibly some minor issue with a solder joint or connector or spring and will just continue with the warranty return to get that one in a happy state :). Thanks again for all the help provided with this. ~DMcC

Ok, here's an addendum... I was mucking around with my Berzerker MTL RDA yesterday, which has a very tight barrel. It happened to be on the Series-B at the time so I ended up doing some pretty serious twisting, and finally some rocking while pulling it to get the barrel off while it was screwed down on the mod. When I finished adjusting the airflow and put it back together, it was immediately reading the resistance correctly (and more correctly than during this entire process), and appears to also be extremely stable, so far. Tried the other tanks/coils I've been working with and had identical improvements. It has just decided to seemingly suddenly behave itself and has been extremely stable since the event in question. Is it possible that something was up with the 510 connector/pin/plate that may have corrected itself due to my reefing it around a bit? Not suggesting this fixed anything at all just yet, but I am not sufficiently informed on what effects the resistance readings to conclude anything so thought I'd mention it here in case it is something that may well have been jarred loose or perhaps now is making a better connection somewhere. May also be temporary for all I know but thought I'd add it to the information here in case it's useful. Obviously, I'm just sitting on it anyway until I get the sandstorm one I ordered so will continue to monitor it, but it's amazing having my TC back. If it holds up over the week or two it will take for that mod to make it to me, maybe all is well... time will tell, it always does (with apologies to Doctor Who for stealing his line). ~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

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

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

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

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

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:

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