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Where have you actually come across a 555 timer in the wild?
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jh15:
I always liked to play with unijunction transistors in 1971. Then the 555 came out and that was more fun. Paid for some samples from an engineer I worked with in a Bell System OEM plant. (I think he got them for free but sold them to me for 4.00 I didn't care.) plus some early PLL chips.
uni's were used in the Bell MagiCall dialers, and I always went or got floor sweepings, don't think dumpsters were around then.

Built a phone answerer out of a 555 and a pll, and 2 cassette recorders, think it was a Radio Electronics magazine plan.

I repaired avionics instruments, and believe it was the Boeing 747 air speed indicator that had a flatpack 555 in it, not sure if it was the same instrument that had a uni. They never went bad. In fact the designs seemed so weird to some.

In my opinion, they were designed to minimize the use of large value capacitors like tantalums and aluminum electrolytics for reliability.

Jokes went around when I got a Quad AC ammeter from US 1 aircraft to fix. It had a sticky analog display needle written on the repair request. Jokes went around if then pres Clinton had found another intern, etc.
dastructhm:
I've torn down many electronic products. I've never seen a 555 timer inside.  :palm:
AVGresponding:

--- Quote from: dastructhm on October 09, 2022, 02:06:48 am ---I've torn down many electronic products. I've never seen a 555 timer inside.  :palm:

--- End quote ---

Here's one for you then:





LED fire alarm beacon, manufacturing date 22/07. The design probably hasn't changed much if at all since then, as the LPCB certification process costs money.
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