EEVblog #624 - Mailbag

EEVblog2 2nd Youtube Channel:

An Engineers Guide To Solving Problems Book:
A really crappy line tracer circuit patent
Geppetto Electronics LCDuino RGB backpack
TmpUSB temporary USB drive:
Sony Mavica 3.5" Floppy Drive Digital Camera
X-Core 16 Core 1000MIPS Analog Slice Kit:

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Electronics Info Wiki:

[LynkedVideos]

Dave, the second paragraph of Scott's letter said "I'm 15 in May." Happy birthday, Scott!

[midnight_commander]

"I want the knob."

-Dave Jones 2014.

[nsayer]

Just a note to say thanks so much for showing my LCDuino during the mailbag segment.

I don't know how to play that Hunt the Wumpus game either, but I wanted it to at least do *something* when you plugged it in, and it was the best I could think of on short notice.

[williamsquires]

Hey Dave, I believe the "transistor" in that "circuit tester" transmitter is a diac that operates like a low-voltage neon bulb (i.e. it forms a relaxation oscillator with the cap and resistor(s) on the board.) I'll bet that, if you remove the LED, and replace Q1 with a real neon bulb, it'll blink! (You may have to trace out the circuit and replace the current limiting resistor with a 100 kilohm one or the neon bulb will EOL!)

[frollard]

15:00
My understanding of the circuit detective is it loads the circuit from the 'detector' side and listens for a harmonic response caused by the module on the other end.

I had one and it worked fine.  This one appears to be snake oil.

[youtubasoarus]

I quite enjoy the Mailbag segments. But my favorite has to be the tear down videos, that's where I learn the most because you go through the boards and explain everything. I really enjoy that.

[fredo]

Hi Dave! I've made a design using XMOS chips for my final Bacc project this year. It was a USB to AVB sound card. Their core boards and open tools and designs are VERY powerful!

[electronicsNmore]

Mailbag videos always fun to watch. :-)

[tubical]

For 09:24 and the "wired" german official letter, yes it is an official letter from our federal government, the one of "Mecklenburg-Vorpommern" the city is "Rostock".

The letter you got is from the political education office, roughly translated....but i think you get the idea...

And inside is a info about your recently made election of the european government.

And don't worry!...As it is no subscription or somelike, it´s just a info, and and additional letter (offical kind of always looks like this....you know?! ;)

The other letter is an invoice, typical german bureaucracy rubbish as it says:
amount of items :1
item cost :zero ;)
Total amount : zero ;) ;) ;)

And an additional cash transfer via local german bank transfer for the cost of 0, 00 ;)

Have fun with it....:D

[midgetsHead]

Yeah we're all here because all of us are getting into engineering. I was in a coma after 2 weeks into med school and discovered that electronics are my way of thinking. You responded to me a year or so ago about an arduino being too simple and now I'm a manager at Microchip! Still trying to learn how our stuff works and just re-familiarizing myself with the programming language. I can read it, I just can't quite write it yet. But if not for the eevblog I would still be stuck in med school. Probably back to first semester or quarter year or whatever since I used to stay up for days buried in books about how things kill other things.

[MoesKeckeEcke]

The plug draws current, then you can sense current "inductively" lol....
Hey Dave as I am a German viewer, the paper you got is send out for free from some kind of educational part of German government to teach you democracy... I had to read them in school. It is just mind blowing that they send them to Australia for free o.O

[douro]

Mavica cameras- very handy and extremely reliable; they were even used by crime scene investigators.  The highest-end model had 40x optical zoom, a 3MP sensor and a Memory Stick slot.

[davadoff]

This video needs to be added to your mailbag playlist.

[NathanaelNewton]

The new microscope is amazing, here's a vote for a teardown of the floppy camera, I haven't seen one of those in probably 15 years? 

[BTNE_Videos]

Hi Dave, please let me know what's the model of that swinging arm for your LCD. Thanks 

[kirknelson]

On your circuit breaker tracer my guess is its generating a wide band rf single, Q1 is possibly used for a nonlinear junction and maybe for its capacitance. 

[DaedalusYoung]

Nice, worked a lot with a Mavica back in 1998-2001. I worked at a local radio/tv station, the photos were used on the tv channel, so the 640x480 resolution was actually just perfect. Quality was pretty good as well, it just didn't perform too well with the flash, it didn't take the extra light into account, so they were always overexposed.

[extremegabel]

The german magazine's from the federal agency for political education not buildings :-)

[GuruBrew]

I did a usage guide on that digital circuit tester here Digital Circuit Detective Tool & Installing a Second Motion Activated Light Switch if anyone is interested. It does work but does require an understanding of how to use it.

[philbx]

Bugger! The shipping for Bob's book on Amazon costs more than the book <grr>