Suggestion for a new t-shirt - Page 1
Forum section: electronics / general

author: Mastro Gippo
author_rank: Regular Contributor
timestamp: April 10, 2010, 05:32:10 pm
content: Watching episode #72, at 17:30, this idea came to my mind. The text should be handwritten, and the image can be replaced with the actual drawing of the schematic. What do you think?

author: MTron
author_rank: Regular Contributor
timestamp: April 11, 2010, 12:40:28 am
content: Hrmmm, i totally agree more t-shirts with circuit diagrams are needed!I could also go with one without the text!you can use the whole µCurrent diagram as the t-shirt....call it the µTee

author: Zad
author_rank: Super Contributor
timestamp: April 11, 2010, 07:54:54 pm
content: There is a 555 t-shirt, next logical one would be a 741 op-amp. The strap line could be something like "Electronics - make a difference"Or, rather more risqué:"Want to see my multivibrator?"

author: orbiter
author_rank: Frequent Contributor
timestamp: April 12, 2010, 11:42:33 pm
content: What software do you use to draw those diagrams Zad? I'm looking for something like that or similar if anyone can recomend something please.ThanksRegardsorb

author: DJPhil
author_rank: Frequent Contributor
timestamp: April 13, 2010, 02:54:50 am
content: Quote from: orbiter on April 12, 2010, 11:42:33 pmI just freehand it in mspaint so far, but I could use something a little easier myself. I went hunting and found a few links.A bunch of schematic symbols for copy/paste all zipped up.Very simple online 'stamp' style program, screen capture and paste to paint or something similar.The improved version of the above, with a little refinement.The upside to these low-tech methods is that you can hop in paint and change colors, annotate, or generally scribble all over what you're doing freehand. You could always use a printout from more advanced software like LTSpice, KiCad, Eagle, or whatever if you've already got it handy.On the t-shirt topic, I saw an illustration in Art of Electronics that made me laugh. Page 1014 has a circuit for using microelectrodes, and the 'Device Under Test' was labeled as shown in the image below. I doubt it could be used commercially, but I was thinking of making a t-shirt with a caption like, "Is that all I am to you, robot?" Unfortunately, I'm tragically bad at snappy sayings, suggestions welcome.

author: orbiter
author_rank: Frequent Contributor
timestamp: April 13, 2010, 10:45:30 am
content: Thanks DJThat improved version is ideal for the moment, I also keep my eye out for a program that I can download though, the I can save, edit my stuff etc. May even have a trial of Autocad Electrical if they do one & it's not too hard to use.regardsorb

author: rossmoffett
author_rank: Regular Contributor
timestamp: April 13, 2010, 11:38:05 am
content: Quote from: DJPhil on April 13, 2010, 02:54:50 amHahahahaha!! I had to look that one up, that's classic!

author: thedigitalprincess
author_rank: Contributor
timestamp: May 14, 2010, 09:22:22 pm
content: I'd totally wear that multivibrator one! HAHA.

author: safarir
author_rank: Regular Contributor
timestamp: May 14, 2010, 10:47:01 pm
content: +1 for the multivibrator one

author: huafeihua116
author_rank: Newbie
timestamp: May 29, 2010, 05:06:35 am
content: I need the 555 t-shirt...

author: merlin8224
author_rank: Newbie
timestamp: June 05, 2010, 10:26:03 pm
content: Just one big line" DON'T TURN IT ON .. TAKE IT APART"howz that ..

author: DJPhil
author_rank: Frequent Contributor
timestamp: June 05, 2010, 10:52:55 pm
content: Quote from: merlin8224 on June 05, 2010, 10:26:03 pmAdd a picture of a screwdriver and it's perfect.

author: dengorius
author_rank: Regular Contributor
timestamp: June 06, 2010, 02:13:27 am
content: I vote for something like thisAhahah j/k mate

author: EEVblog
author_rank: Unknown
timestamp: June 06, 2010, 04:44:27 am
content: Hilarious!

author: EEVblog
author_rank: Unknown
timestamp: June 20, 2010, 09:59:02 am
content: Quote from: DJPhil on June 05, 2010, 10:52:55 pmDone.Two different designs now available:http://www.zazzle.com/eevblog*Plus two other custom T-Shirt designs.I really like how the FSM one turned out.Dave.

author: merlin8224
author_rank: Newbie
timestamp: July 05, 2010, 09:21:28 am
content: Quote from: EEVblog on June 20, 2010, 09:59:02 amwohoo .. never thought you would actually use that .. looks great Dave ..heres one more ..A glass of water half filled with a caption saying "6dB full or 6dB empty"... a geeky version of the optimistic and the pessimistic attitude concept.cheers

author: RayJones
author_rank: Frequent Contributor
timestamp: July 05, 2010, 10:46:59 am
content: Quote from: merlin8224 on July 05, 2010, 09:21:28 amUm, does water squared = power?If not then the half glass is simply 3dB full or 3dB empty. ie -3dB *is* half of the final quantity, being water level.

author: DJPhil
author_rank: Frequent Contributor
timestamp: July 05, 2010, 11:00:00 am
content: Quote from: merlin8224 on July 05, 2010, 09:21:28 amI can work with that!

author: Unknown
author_rank: Unknown
timestamp: July 05, 2010, 11:09:53 am
content: -3dB, since decibel is a logarithmic unit, things get screwy close to zero (+3dB is twice as large as 0dB, so the 0dB point is 25% full?). If 0dB = 100% full, then 50% full = -3dB (when talking about voltage/current). So 3dB full seems wrong...*Goes back chasing lice*

author: EEVblog
author_rank: Unknown
timestamp: July 05, 2010, 11:49:31 am
content: I recon it's 6db down!Dave.

author: Zero999
author_rank: Super Contributor
timestamp: July 05, 2010, 11:53:28 am
content: Depends on whether you're talking about voltage/current or power.

author: EEVblog
author_rank: Unknown
timestamp: July 05, 2010, 12:31:51 pm
content: Quote from: Hero999 on July 05, 2010, 11:53:28 amI recon water is a magnitudeDave.

author: RayJones
author_rank: Frequent Contributor
timestamp: July 05, 2010, 10:52:33 pm
content: Yep, the water level is a magnitude, as is the level of a full glass of water.You simply cannot choose to square a magnitude to get a magnitude, it does not work that way.So 3dB down it is.Likewise, a voltage at half its expected magnitude is also 3dB down from the expected full voltage.If your voltage is being measured to calculate the signal's power, then yes the power is 6dB down.The frame of reference in the initial assertion is magnitude, that being a full glass of water, not the power of water in the glass.So, until somebody can demonstrate the power equation for H20, 3dB it is.The fundamental being dB's express a ratio, and dB = 10 x log10 (test/reference) => -3dB = 10 log10(0.5/1.0)Stating 6dB proves you are not worthy of true geekiness, and are instead randomly rambling something you read in a text book and never fully appreciated what a dB isPeople *will* point and laugh

author: EEVblog
author_rank: Unknown
timestamp: July 06, 2010, 12:56:40 am
content: You are failing to take into account the rarely understood voltage-water dualityThe true practical nerds would understand that 6dB down is the correct solution.Dave.

author: RayJones
author_rank: Frequent Contributor
timestamp: July 06, 2010, 03:21:32 am
content: AH, of course, I know what I left out.If you consider yourself a square then it is 6dB

author: Zero999
author_rank: Super Contributor
timestamp: July 06, 2010, 09:26:06 am
content: Using dB to measure a volume of water is meaningless because it's a dimensionless quantity. If we're going to measure the quantity of water, we need a reference.In this case we could use the volume of the glass to be the reference or if we're talking about the hydraulic analogy for voltage we'd be referring to the pressure which is only dependant on the depth of the water so the water level would be the reference.

author: RayJones
author_rank: Frequent Contributor
timestamp: July 06, 2010, 10:13:07 am
content: Ah yes, but a dB is also a dimensionless quantity!a dB is purely a ratio ofanything.If you wish to reference then to something tangible, then you need to specify a subscript.eg dBm in the RF world is 1 mW into 50 ohms. If you then measure a signal, it is as a ratio against 1mW.You can also validly state that a signal is 3dB down, but without an original dBm reference level, you won't know the actual power.ie dB != dBm.Back to our glass of water, I agree that "full" would be the reference, and all calculations would flow from there (misguided or otherwise). oh yeah, sorry 'bout pun (wrong thread)

author: merlin8224
author_rank: Newbie
timestamp: July 06, 2010, 11:27:12 pm
content: wow that lead to quite a bit of discussion. For my suggestions i am picking up relevant lines from the videos.This one comes from a simple example that Dave had given for understanding purposes (in his dB video at the end) and of course i had mentioned the context in which i am suggesting this.I saw water level as a magnitude. But then again you can always correct me on the caption and change it if you want for a more accurate and geekier version.cheers

author: Rhythmtech
author_rank: Regular Contributor
timestamp: July 14, 2010, 08:29:02 pm
content: Band style T-Shirt - Eddy Current and the Stray Transients with fuse symbol as the logo vertically behind the letteringL is for Inductor! with the inductor symbol as the underline for the letteringWhat's Your Power Factor? with Real Power/Apparent Power beneathI've properly vented my lame geekness for the day...