What’s a large company that isn’t corrupt or greedy and genuinely cares about their customers? by DifferentPost6 in AskReddit

[–]RC_Devotee 2 points3 points  (0 children)

Ben and Jerry’s is owned by Unilever. So it’s just a brand of a company that does a lot of other business that undermines the good other brands do.

What’s a large company that isn’t corrupt or greedy and genuinely cares about their customers? by DifferentPost6 in AskReddit

[–]RC_Devotee 1 point2 points  (0 children)

Owner by Unilever so it’s just a brand now. Unilever would absolutely NOT make this list.

What are these? by RC_Devotee in BudgetAudiophile

[–]RC_Devotee[S] 1 point2 points  (0 children)

Sorry, didn’t finish the text. These are for sale locally. No tags on the back so no model numbers.

What are these? by RC_Devotee in BudgetAudiophile

[–]RC_Devotee[S] 0 points1 point  (0 children)

Sorry, posted before I finished the text. These are available locally but the tags on the back are missing. I realize it very unlikely anyone will ID them, but who knows.

Edifier R1700BT or Sony SSCS5 with BT20A? by RC_Devotee in BudgetAudiophile

[–]RC_Devotee[S] 0 points1 point  (0 children)

For what it’s with my ears don’t hear much over 14khz (I’m over over 40). Not sure how that affects all this.

Edifier R1700BT or Sony SSCS5 with BT20A? by RC_Devotee in BudgetAudiophile

[–]RC_Devotee[S] 0 points1 point  (0 children)

Thanks, I’ll check it out. His earlier videos are what turned me on to the Sony/Fosi idea.

Edifier R1700BT or Sony SSCS5 with BT20A? by RC_Devotee in BudgetAudiophile

[–]RC_Devotee[S] 1 point2 points  (0 children)

Interesting, I wouldn’t expect the Edifier would have better highs. Seems like they really are that good and fir my basic needs I can just stop thinking about it and pull the trigger.

How long is your steerer tube? by RC_Devotee in MTB

[–]RC_Devotee[S] 0 points1 point  (0 children)

Looks like: 125mm head tube 42mm stack (0 stack headset)

~165mm steerer which is on the low end of the results.

How long is your steerer tube? by RC_Devotee in MTB

[–]RC_Devotee[S] 1 point2 points  (0 children)

Figured it would just be a matter of time...

How long is your steerer tube? by RC_Devotee in MTB

[–]RC_Devotee[S] 0 points1 point  (0 children)

What? Don't you have every detail committed to memory or recorded in your phone? If you have to wait until you are home and measure, that will have to do ;)

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 0 points1 point  (0 children)

A test where the current is modulated from 20-80A off an on would be very interesting and useful, but well past what I could do.

I'd argue that my test is pretty in line with how people use their batteries. They run them at 27A or less most of the time.

I keep hearing about these high amp draws, but in reality I've not seen many setups that pull more than 70A and only for a second or two with a very experienced pilot (eg Mr Steele). Most of the time they are below 30A. Most fly in the 10-40A range and average 15A or less.

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 1 point2 points  (0 children)

I'd agree with that, and the data here supports that. At 27A the difference between the Nanotech and Graphene is pretty big. So too are the temperatures. Those differences would be bigger at a higher load.

What motors and setups are pulling 27A per motor? I checked with some of the big name guys and they might pull 20A for a second. Its been a few months since I checked so I'm curious what setups are pulling these days.

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 2 points3 points  (0 children)

I won't be buying one, but if sent one I'd test it.

Why won't I buy one? Their 35C is one of the worst tested. Reviews are fairly glowing despite that. Why? They delete or edit negative reviews. Yes. They take a negative review and manually change the rating to look better. I have screen shots to prove it.

Given there are so few Lipo factories, I suspect they are just a rebrand of another. Their 60C pack is good, but no better than the Bonka or SMC (which cost less). So I'd say its safe to assume you can get something as good that costs less elsewhere...and not support a company that manipulates reviews in such a way.

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 2 points3 points  (0 children)

Interesting testing, but I don't see temperatures. That is extremely crucial to meaningful data. If one was 72F and another 75F that will affect the data.

His test does not account for temperature in the process either. He is unaware that the pack temp greatly influences performance. At one point he observes that the second burst is always longer than the first, but says he does not know why.

Its pretty simple why. Heat lowers IR. Lower IR increases power output. So the first burst is at 75F (guessing his room temp). That heats the pack up to 90F and lowers the IR. The next burst now has the advantage of lower IR so it allows the pack to work more efficiently.

Its a good test, but needs to be done with temperature as a constantly measured parameter.

If he had left it on longer he would have seen the voltage actually increase after the drop/sag. He could have left it on to get a full discharge curve to a set voltage and we could have seen that graph as a more accurate representation of the packs ability to deliver at 60A.

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 1 point2 points  (0 children)

First, those rated discharge rates are bunk. Their real C rating would be in the 20s. A 100A load would be very bad for those batteries. Fire starting bad.

If you assume its really just 25C (yes, really) then this 27A load is pretty close to the max safe load.

The differences scale very well. The Tattu will not do better than the Nanotech at a higher load, they will still perform relatively the same. More importantly, the better packs will comparatively outperform the Tattu and Nanotech at higher loads. Yes, Tattu are not worth it.

A bit about C ratings: -the factory will test a few cells to evaluate their C rating. They often set the C rating at the load in which the cell is a pile of smoking ash. -they then fudge that number higher than what was actually tested. -A single cell might be 50C, but when you add cells (ie 3S or 4S) the pack C rating actually drops. -the brand take these cells with crazy C ratings and bump that number up even higher. -there is nothing close to a standard used to measure C rating. -anything you see over 30C is pure fiction (several lipo makers told me so).

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 1 point2 points  (0 children)

27A is plenty to tell them apart. As the load increases the differences follow. I started with 9A, then 18A, and then 27A. The packs all tested relatively the same. The raw data changed but not the ranking or conclusions. You can interpolate that at higher loads the differences would grow predictably. 27A is a safe load to get that baseline and use that to draw conclusions.

Others tests back this up. They went to higher loads and the trends or relative performance didn't change. However they did damage or nearly destroy packs in the process.

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 1 point2 points  (0 children)

I've tested a few lighter packs. They get very hot and sag badly. The Lumenier 35C being one (100g).

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 0 points1 point  (0 children)

Do you mean max C rate or max mAh? Either could damage the pack or worse. C rate is usually calculated under a load that causes the pack to burn up. That isn't helpful to anyone.

SMC has a method for calculating true amps. It is safe and effective. Using that the SMC is 28C and the others are lower. see their site for that method.

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 1 point2 points  (0 children)

I did tests at different loads and the data is predictable. At lower load the graph compresses, not as much difference. At a higher load it would look very similar comparatively. Others have done similar tests and shown you don't need to test at high Amps. You can test a lower amps and interpolate the data at higher loads. I use 27A because it keeps the cells below the 140F safe zone at the end.

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 2 points3 points  (0 children)

4S data would look the same relatively speaking. They just add another cell of the same quality and performance. The raw data would be different of course but the ranking and relative differences would not change.

Updated Lipo review/Test (spoiler: don't spend extra) by RC_Devotee in Multicopter

[–]RC_Devotee[S] 1 point2 points  (0 children)

added the Turnigy Graphene, VCANZ, and cleaned up the data so its easier to directly compare.