wight; I see your point but none of the USB battery power boxes seem to clearly state in their specifications that the capacity listed is at 3.7V. I noted it because SOME units list it on the power unit itself. As for changing capacity with different current draws most such units, except the highest power ones, are limited to outputs between 1 and 2 Amps at 5V and per HKJs 18650 battery reviews most decent batteries have quite close to the same capacity until the current draw becomes quite high.
My major objection is not so much that they specify things the way they do but that they carefully DO NOT MENTION that the capacity is listed for 3.7V as it seems apparent, based on customer reviews, that many are thinking that the capacity being listed is output capacity @ 5V. The capacity specifications listed are incomplete as long as the voltage involved, or the theoretical watt hours capacity, is not listed. One unit I have actually lists voltage and watt hours but only on the device itself, not in the Amazon listing. Not even a statement any where that the capacities listed are battery capacity rather than output capacity.
Give the customers full information on tech devices so the technically educated ones can make informed purchases with full knowledge of what they are getting.
IMO it doesn’t matter very much as long as we’re all playing by the same rulebook (where all manufacturer’s spec @ 3.7v). It allows easy comparison on the only metric these people can be semi-trusted about…
When it comes to output currents, this is where it may get trickier than you realize. The batteries will be fine at 2A, 3A, etc - they don’t sag at all. [Especially since they are in parallel of course!] The boost circuit? Not fine. Trying to get 2A or 3A @ 5v out of a bank of cells which is at less than 4v gets some pretty low efficiency out of those boost circuits I think. I’m assuming that’s where your most significant variations will be between chargers. That said, I’m not the most educated person on this subject so I’m happy to be proven wrong about the efficiency tanking.
That seems like a pretty good deal. At one time it would have been a very good deal. I would rather spend $40 more for a TK-61 though. More battery capacity, larger reflector, more heat sinking, and more moddable for higher voltage emitters like the MT-G2 and whatever comes out in the future.
Thanks for the comments. I posted that deal there. To be honest I am not sure if it is a good deal or not. Mine was from at least two years ago at $120. But nowadays it may not quality as a satisfying thrower any more.
They now have both neutral white and cool white for $79.95, last week the cool white was $10 more. Just received my neutral white today. Now have 2 stock and 1 modded TN31. The modded one will out throw anything I have. My modded one was done by TomE but I think I’m going to try and mod the other cool white and leave the neutral stock. To me I think this is the best deal going especially if you can mod. One more thing, the ones on sale at Amazon are shipping only in a cardboard box, not the aluminum case.
I’ve been meaning to buy one of these for a while now, but just couldn’t fork over the $150+ for one. Definitely going to buy one today. Thanks for the stellar find!
EDIT: It is now sold out for the $60 price tag. It’s now back up $88. Looks like I’ll have to wait until another great deal like that comes around.
If you missed this deal, Black and Decker makes a great rotary tool for a tiny price. Usually B&D stuff is utter crap, but this is the exception. It outlasted my Dremel brand tool easily. The cost savings is partially from B&D not including a bunch of accessories, but they use the same bits as Dremel so you can just get the ones you need.
I'm sure everyone knows by now. Amazon is having some type of big sale tomorrow just for Prime members. I didn't search very hard, but I don't see a list of items that will be on sale. If anyone finds something like that, please share it. I don't have a Prime membership, but I'm curious.
Go to Amazon home page and click on the Prime day banner. Scroll all the way down and there’s a slider with today’s deals. Click over a few pages and you’ll see a bunch of items starting from 2am and on. Shows the item, but not the deal price.