ebay and their silly algorithms... "You searched for transistors recently, here's some helpful links to similar products" followed by a list of random auctions for every type of transistor you could think of... ![Face Palm :palm:](https://www.eevblog.com/forum/Smileys/default/facepalm.gif)
ebay obviously doen't understand that people don't search for ANY transistor, but a particular part No. Even worse, the search was for a 7912CV linear regulator, NOT a transistor.
McBryce.
Pardon my ignorance, but what is special about it that you have to resort to ebay to find one, rather than buy brand new from any electronic distributor ?
I tried googling for the datasheet but somehow it won't even fine one ?!
![Shocked :o](https://www.eevblog.com/forum/Smileys/default/shocked.gif)
Every time it gives me instead the datasheet for the L79XX series.
I don't know what the prefix ' L ' means... thought maybe LDO, but according to the datasheet, it is not an LDO. So I don't know...
I have a random collection of 50 of these regulators to sort and organize, right now. There is a great variety of prefixes and suffixes and I can't even figure out what they mean. Datasheet are either non existent, or confusing.
For example my datasheet for the L79XX series says that the 'CV' and 'CT' prefixes designate the package type. CV is for T0220 and CT for TO3.
OK... except in my stock I happen to have a few TO220 that are marked 'CT' !
Some are market CVT, don't know what that one is.
Some have prefix 'KA'. Like KA7805... Looks like 'K' stuff is a prefix used by Fairchild... but looking at the datasheet for it, it just looks like a regular 7805.
So.. the prefix doesn't necessarily mean anything does it... so how do I know what the prefix 'L' means, in what does it differ from a regular/vanilla/ non 'L' prefix chip ?
![Confused :-//](https://www.eevblog.com/forum/Smileys/default/confused0024.gif)
Does it even mean anything at all, from an electrical properties perspective that is...
I also have a dozen regulators that have an 'A' suffix. Like 7805A say.
Again the datasheet gives no obvious clue on the front page about what's special about this 'A' suffix.
All I can see, that's obvious, is that they are all branded ' NEC ' AND all come in a special 100% plastic / isolated TO220 package. No metal tab.
So the 'A' might either mean nothing and just be how NEC chose to differentiate their regulator naming, just for the sake of it. Or, the A refers to this plastic/isolated package.
Or.... it refers to whatever electrical characteristic and good luck knowing what it is, as the datasheet sure doesn't make it obvious on the cover page.
I didn't expect something as simple, mundane as 3 pin regulators to be such a shit show.
It's a huge mess and am not too sure how to go about sorting them now... it drives me completely nuts.
I think what I will do is mix them all. Only sort them by voltage and polarity, and that's it.
I might test them all on a bread board to see if some are LDO, and put these aside from the rest, but that's about it.
If I need something very specific, really very specific, and it's not good enough to pick a random one from my stock, then I guess in this case I can just go buy it brand new, hence I have the datasheet for it so I know what it is exactly.