New SX-350 Board from China
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I only added the link for the SX350 as a indication what the chip might cost. If something costs 50€ in europe, it will most likely cost $50 in the US. But lets hope the price will be even less than that after a bit of time.
Not much time to test this weekend since the wife had lots planned for me I was unaware of. 
I did get to test with .7 ohm & .4 ohm coils a little. Found my scope but my frequency counter is still buried somewhere in the boxes of stuff from the man room. (now daughters bedroom since she moved back in) My scope is old so it doesn't have any bells or whistles and I could only find my precision 5V square wave generator so that is what I used.
With both the .4 ohm and .7 ohm coils I found a sawtooth waveform on the output. It is more pronounced at higher wattages and with the higher ohm coil. I would guess it to be in the range of 750Khz to 1.25Mhz but without my frequency counter I can't narrow it down further. With it set to 5V = 5 full divisions (full screen) on the reticule of the scope it was small enough I couldn't guess the amplitude of the sawtooth. Going to AC input and to the .15V/division scale I would guess it at around .15V with the .7 ohm coil at 30W & .05V at 5W, and .075V with the .4 ohm coil at 30W and .025V at 5W. Again those are not accurate measurements but interpolations on my part.
The display on the board for the output voltage was higher than actual measurements and varied with less difference at lower wattage and lower ohm coil. Max was about .08V and min was about .02V.
With a 3.61V measured unloaded battery voltage it is now showing 3.74V on the board display. Also, it must not poll the battery voltage during firing since it stays at 3.74V during firing even though the battery is dropping from 3.61 to 3.45V during 30W firing of the .4 ohm coil. I saw no ripple at the battery terminals.
Did extensive testing at 30W with the .4 ohm coil (triple braid R41) in an RM2 atty dry without the cap on. The atty got almost too hot to touch and the board was warm but not hot. Of course there is some natural convection cooling for the board, but it is partially enclosed with dense foam against the back inside the DSL filter case.
Conclusion: The output is well filtered and the only complaint I have is the accuracy of the battery voltage displayed. That could just be the board I have, but I do know that another member also tested the battery display vs actual measurement (unloaded) and found the same. The board does not seem to be highly stressed at 30W so I believe the 35W upgrade will not be a problem.
Thats all the time I have for now.
I did get to test with .7 ohm & .4 ohm coils a little. Found my scope but my frequency counter is still buried somewhere in the boxes of stuff from the man room. (now daughters bedroom since she moved back in) My scope is old so it doesn't have any bells or whistles and I could only find my precision 5V square wave generator so that is what I used.
With both the .4 ohm and .7 ohm coils I found a sawtooth waveform on the output. It is more pronounced at higher wattages and with the higher ohm coil. I would guess it to be in the range of 750Khz to 1.25Mhz but without my frequency counter I can't narrow it down further. With it set to 5V = 5 full divisions (full screen) on the reticule of the scope it was small enough I couldn't guess the amplitude of the sawtooth. Going to AC input and to the .15V/division scale I would guess it at around .15V with the .7 ohm coil at 30W & .05V at 5W, and .075V with the .4 ohm coil at 30W and .025V at 5W. Again those are not accurate measurements but interpolations on my part.
The display on the board for the output voltage was higher than actual measurements and varied with less difference at lower wattage and lower ohm coil. Max was about .08V and min was about .02V.
With a 3.61V measured unloaded battery voltage it is now showing 3.74V on the board display. Also, it must not poll the battery voltage during firing since it stays at 3.74V during firing even though the battery is dropping from 3.61 to 3.45V during 30W firing of the .4 ohm coil. I saw no ripple at the battery terminals.
Did extensive testing at 30W with the .4 ohm coil (triple braid R41) in an RM2 atty dry without the cap on. The atty got almost too hot to touch and the board was warm but not hot. Of course there is some natural convection cooling for the board, but it is partially enclosed with dense foam against the back inside the DSL filter case.
Conclusion: The output is well filtered and the only complaint I have is the accuracy of the battery voltage displayed. That could just be the board I have, but I do know that another member also tested the battery display vs actual measurement (unloaded) and found the same. The board does not seem to be highly stressed at 30W so I believe the 35W upgrade will not be a problem.
Thats all the time I have for now.
Yes, I believe if you read my last several posts, that, is exactly what I found. NO issues what so ever at 35 watts. A breeze. Though, I went for a resistive load, just to keep things stable. And, it was easier. Several Sand Ballast resistors, high power, in parallel, coming up to 2.xx ohms. NO issues what so ever. On a 450 mhz HP digital scope. Though, what I saw, I don't know If I'd call it a sawtooth, more like an infected tooth! Very strange trailing edge, IF it were a square wave, a strange Slope, IF it is a sawtooth.
I wonder if what you are seeing has to do with capacitive resistance/inductance on the load. Did you happen to see the wire wound teroid on the board? Do you really want/expect a pure digital signal?Nice work.... ty
Hard to tell with my old equipment and too much gunk on board to trace, but I would say they are doing synchronized full conductance 4 switch method. That accounts for the strange sawtooth. Like I said though, well filtered and this ripple is very small so it won't have any effect.
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Couldn't tell you. I never checked the 20 I had and it will be a few weeks before my 30's arrive. Will test a 30 when they arrive.
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Wow, really nice info guys. Nice job. I'm designing a wooden box mod made out of Bubinga wood with a very unique design for possible production and this us helping me decide on which board to put in it. I may make 2 models, one with a dna 30 and the other with the SX350. If only I could get my hands on those boards lol
$90? Well that's a big bag of NOPE. Thanks for the info nontheless!
I think the price is just speculation right now. Won't know until they actually hit the suppliers here in the USA.
I was told my a US vendor that he would have them available next month in 10 lots for $55 each including the USB board. I didn't ask about single units. If he PM's me to let me know it is ok to name him I will.
He WON'T he is already receiving LOTS of calls to his HOusel, shop, and everywhere as The COMPANY is giving out his Name/Address to "QAualifed" individuals............ HeY Dr. Beaker, It turns out you and I have a FRIEND in common. A YIHI friend!
Really ok that's cool...
I love this board that's why I did the write up build on my crude radio shack box mod. People see it and cant believe what it can do. People around here spend big bucks for mechanical mods to drive their sub ohm RDAs...
He will NOT be the only one. Nor the largest one. As in Volume. There will be MANY. No big secret there! I know of one myself, the one that got me mine. (SX350 that is). And, they are everything they are advertised, GREAT. Mine hs been abused, by a CRACK abuser. There is ONE out there, who will 2nd that statement! The ONLY mod, I have NOT been able to tear up in one fashion or another, is a Hades Mod. That hing is bullet proof, SO FAR 
. Fits the hand JUST right, but, the button is just a TAD hard to push, I'll deal with it. I had my SX350 on a test bench, with jumpers, and have been abusing the MESS out of it. And, I cannot BELIEVE it has not failed yet. It is fired back to back non-stop, till cutoff, then fired again, continually. Only stop, being battery changes, or overheats. (On attys). I switched to a resistive load, multiple paralell sand ballast resistors, for a total of .2x ohms. That is the way to stress it. Don't like the button, they have on it, but, it takes seconds to change that out.
. Fits the hand JUST right, but, the button is just a TAD hard to push, I'll deal with it. I had my SX350 on a test bench, with jumpers, and have been abusing the MESS out of it. And, I cannot BELIEVE it has not failed yet. It is fired back to back non-stop, till cutoff, then fired again, continually. Only stop, being battery changes, or overheats. (On attys). I switched to a resistive load, multiple paralell sand ballast resistors, for a total of .2x ohms. That is the way to stress it. Don't like the button, they have on it, but, it takes seconds to change that out.NO, that would be such a waste! i WAS SIMPLY stating my ability in tearing up mods. And, that the only one I had NOT been able to destroy, was a Hades I bought. A well machined, and beautiful piece of equipment. The SX350, is NOT in a Hades............................
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