I think I am starting to really lose it....

I was building the "Evasive Beeping Thing" from Make. A search through all of my "parts" finally got me resistors and caps of approximately the correct values I wanted *even though they are not specified in the article :-( ". After nearly a fortnight, I finally was ready to test it. hooked up a nine volt battery, and.....nothing. Fearing the worse, I touched the 555 IC...and it was hot as blazes.
2 days of inspecting the circuit and trying to make sure no shorts were occurring, I finally gave up and unsoldered the whole thing.
I then through together a quick 555 timer circuit using an ic socket, in order to test if I had destroyed my IC. That didn't work at first (but just in case, I tried a 555 I knew was good, and that did work). Just before throwing out the assumed defunct 555, I looked at it under a brighter light (and low and behold, on the IC was written in very small worn type: 741. It was an op-amp ! I could have screamed....*sigh*. Oh well, at least I got a tester out of the deal LOL
*sigh*


Picture of I think I am starting to really lose it....
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Plasmana9 years ago
Ouch! That is the problem, most of the IC's are so alike! That reminds me of the recent electronic accident I had, I blew up the PCB copper tracking...
P2210039.JPG
Goodhart (author)  Plasmana9 years ago
I don't mind them being alike (makes using sockets easier), but the type written on it (part ID) was so very tiny and light.....I had troubles determining just what it was. BTW: how did you do that to the copper tracking?
Yeah, that is same for me... The copper tracking blew up from too much current, I accidently put the solder tracking on the wrong copper track (as you can see in the picture) where it carries very little current. Oh, and that is my flyback transformer driver.
Goodhart (author)  Plasmana9 years ago
My 555's are printed on pretty plainly, but that 741 was lightly etched, and if there had been any printing on it, it had worn off in transit.
Oh, that makes sense then.
Goodhart (author)  Plasmana9 years ago
Yeah, with a CFL light right up against it, I finally did see what was printed on the 741 grrrr. :-)
Here are more pictures...
P2210042.JPGP2210035.JPG
guyfrom7up9 years ago
haha i don't like 555s, too many external parts and it's a hassle...
What do you use other than the 555 timers?
P2210039.JPG
Goodhart (author)  guyfrom7up9 years ago
what are you thoughts about using a 741 Op Amp instead LOL
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