Thanks!

Yeaaahhhh... David POWEEEERRR!!!

yes, because making both features available is too much of a choice, and making them available on mobile devices too much of a technical difficulty.

Video is very underexposed

Haha! Yep, That is because I am terrible with cameras.

i think he mentioned in the other video when he was using the microscope that the other desk he had it on was screwed down and very solid and yet still saw vibrations

Put the heavy table on suspension.

Exactly. Scanned down the comments expecting lots of people to have raised this but they don't seem to have. A standard LM317 needs between 1.5 and 2V to maintain regulation at 300mA depending of temperature. Add to that the 1.25V dropped across the current sense resistor and it's 2.75 to 3.25V. Looks like David needs a bit more practical electronics experience.

Easiest way to check if the the final circuit is regulating is to check the voltage drop over the resistor. It wont be 1.25V if the power supply is too low.

Agreed. Looks like it's just us two commenting on this.

Yup, I concur, I'm not even in the office lol its Sunday. I responded to Graham's comment above.

I reckon the microscope is dearly offended by the USB current source, yes

It's not really a "USB current source". Just using a USB connector as a source of 5v. There's also nothing wrong with using an LM317 for this task.

Would you prefer verbosity such as "USB-powered constant current source"?

Who said that there is something 'wrong' with it?

I think the audio volume was too low at some points but overall it was comprehensible - even for a non-native speaker

I disagree. Industrial grade super clean cotton is generally recommended.

on the 2nd channel uploaded on Sep 3, 2015

Thanks. That was nice to see again. I wonder how many minutes were cut out from this video figuring out again how that bastard works ;-)

tohopes would be very funny if dave2 did the same thing to dave1 if he got to editing as well. Thumbs up to dave2 being a permanant host. Though saying questioningly Power supply of doom? is there video of why this power supply earned the nickname?

yep, there is a video, gotta go back 6-8 months at least I just remember it being about power supplies, possibly a review, and then this came in on a tangent, it was about UI simplicity

I appreciate your response but its no problem, it was my idea for him to correct me. Its an Aussie joke, Aussies obsessively will correct you if you pronounce Z "incorrectly". It reckon it was a fun edit :)

I liked the video. I also didn´t mind Dave's voice over. Don´t get me wrong, it wasn´t necessary - but it added even more value. Two heads are better than one.

The voice over was only echoing what I was shouting at my monitor, anyway : )

its either in the previous video or one of the eevblog2 videos he shows the specific camera used.

Hopefully your not trolling and want an actual response. This was a two birds with one stone solution, if inadequate current (less than 300 mA) achieved sufficient brightness then job done. If not power from an alternate source and get the full 300mA. It was only a few minutes of work for a solution for both scenarios. I probably should have kept more footage, not very good at editing at the moment and I wasn't sure what to keep. In both scenarios the LED is safe from over current. Device is temperature stable at 300mA, building is aircon'd + heatsink sufficent. If your curious its running at about 50% relative luminous flux (166mA) what it could, at 300mA it would be at about 80%. We didn't yet need the extra brightness, might later, we will see. I know that the multimeter doesn't include forward voltage of LED or set drop, this is pretty basic and ultimately it didn't matter. It showed that I didn't pick the wrong resistor and that it wasn't open circuit or shorted, it also showed that the LM317 was functional as many were second hand. The test meant that I could be sure that I was indeed protecting the LED from over current for both scenarios. Thanks for the feedback, would you prefer longer videos with the extra details that fully justify a design decision or more like a project summery?

Why on earth do you think I'm trolling? You made a schoolboy error and I pointed it out. Trying to justify the error does you no favours. That's "you're" in the third para BTW.

Christopher Stone I got mine in one of my local Hardware Stores (33 Drawers/Unit for 8.99€). The shipping costs from China will ruin the price advantage you get.

So we should thumb this up to fuck with them :>

Maybe people would press thumbs up if he said "winner winner chicken dinner" a couple of times, and Bob's your uncle.

Or perhaps the video wasn't that interesting. It's a good start, though.

I think I speak for everyone here when I say nobody cares how to clean a microscope.

basshead Yet you clicked on a video with that title and then proceeded to comment on it, why?

next to tuv of coarse1

the other video labeled episode 992 maybe...

Unknown.

david aka dave2, has been working with dave for over a year on and off while also doing university which he recently finished. dave bought an old microscope, it needed cleaning, some people do care. mailbag = hoard :P

Ah!

Still confusing tho.

I took him to be from the UK when he first appeared - I commented on it at the time - but the Australian inflection is very infectious.

I am an Aussie from birth. Dave and I grew up in different areas and times in Sydney.

I understand the confusion, but in this case it is correct, Z is the 3rd dimension. On the ground, map or piece of paper (or the table from the microscope), the dimensions are X and Y, the Z is the height above it.