102 years for the Flip Flop

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Joined 2003
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You *and* Hack-A-Day need to get with-it, sharpen your game, polish your calendar. From an email to my family geeks:

me said:
A guy on a tube-amp chatroom found a thingie with Octal plug on bottom and 12AU7 holes in top, marked "FLIP FLOP", Electronic Engineering of California ZA 8336.
Dropbox - photos

In explaining it, I realized that this is 100 years since the Eccles & Jordan "Trigger relay" patent of 1918.

Eccles & Jordan Invent the Flip-Flop Circuit, the Basis for Electronic Memory : History of Information
Flip-flop (electronics - Wikipedia)

Oddly, considering later uses, E&J did not note the electronic set/reset function. They actually triggered it with a microphone "snapping the thumb and finger at a distance of five feet from the telephone". They re-set by "dimming the filament"!

The Colossus computer of 1943 used flops. The flip-flop types SR, D, T, JK seem to originate from a 1954 UCLA course.

The guy with the thingie-module was astonished that his PC and cellfone contain millions of flip-flops.

Note that my email is 3 months before the Hackaday article.

Those who are doomed to repeat the past are.... uh, I forget the rest of that saying...


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... the carcinogenic theory ... Not for me.
I don't actually wear crocs Osvaldo, I only said that for comedic effect. :)

I've heard people say "My shoes are killing me!", but you've put a new slant on that expression!

I wear shoes with leather uppers and soft synthetic soles. I presume you only wear shoes with leather soles in order to avoid the carcinogenic effect of plasticisers.

Even leather uppers may not be safe as benzidine is used in leather dyes and is linked to bladder and pancreatic cancer.

Not surprisingly, it appears that shoe manufacturing workers are at greater risk than shoe wearers: https://oem.bmj.com/content/oemed/53/6/394.full.pdf

I've found one piece of evidence that wearing flip-flops can cause cancer, but that is skin cancer due to exposure to UV radiation. Flip-flops linked to skin cancer - Telegraph
It may sound strange what I will say here, but it is the more sincere true: at home, I use high heels or be completely barefoot on hardly warm days like those. When I say high heels, I am speaking of 20cm or more of heels. There is a "pleasure" brand that I can buy here. Take into account I strongly like and enjoy high heels and this brand makes them hard to dance. So they support my #40 size and 90Kg of weight. At street, only "the 3 stripe brand" and at work, it is mandatory safety shoes. Surely a doctor or physician will say that they are bad for me, but what isn't bad to the health?

Respect to carcinogenic or not, I am not sure if there are any true in both senses, it depend on who paid the survey or the investigation job. I only repeat what I listen to, no expert at all in this aspect, and too not in many others :)
Keep in mind that originally when high heels were created, they were to be used for men. I don't remember exactly, but it seems to me by Leonardo for the warriors can use more safely their riding. Still now, some "important" politics use them to seem taller. Not my case, certainly I use them because I simply like them.
Now, in 30 minutes starts my vacations, so if the thread is not closed, we can continue in 17 days. Enjoy my absence. I will enjoy High heels in this time.
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