Bad L78L05 batch??

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the dude of dudes

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I picked up a bag of +5v regulators in TO-92 packaging off Ebay for cheap, but I'm starting to think the whole batch is toast (???). They're stamped ST L78L05, on the second line is a single letter 'A', and on the third line is GE 542. I assume these to be a standard +5v regulator, but when I use in a circuit with a 9v alkaline battery I get 8.5v out instead of 5. I've tested several of them, all with the same results. Are they toast?
 
Your problem sounds very similar to a problem posted a while ago.

Have you tried swapping the pins? The package might have some markings on it, but it might be a faulty? Try it. You've got nothing to loose: D
 
Buying no-name-brand stuff that is made in a country you never heard of from E-Bay is not a good idea.
 
I had the pins reversed. The orientation is opposite a 78M05, and I misread the datasheet as being the top view instead of the bottom view (or is it the other way around?? hmm..). Anyways, works like a champ now! Thanks for all the replies!

I only paid 10 cents per component on E-bay, compared to $2 at my local wholesaler. Mouser is cheaper, but I need a large order for me to offset the shipping cost. I cant believe the markup on some components by local sellers.
 
the dude of dudes said:
I cant believe the markup on some components by local sellers.
Click to expand...

I wish we had some local sellers so competition would keep the price down. Only one supply house here sells hobby-type components, and that is a very expensive, limited selection. One CD4017 here costs $2.94 plus tax, and a six-pack of 74LS02 is the same price.

Unless one is in a major metropolitan area, to satisfy his inner-economist one has to buy mail order. That usually means high shipping-and-handling charges, minimum orders in some cases, and the ever-present danger of faulty or wrongly-ordered merchandise.
 

Wow! That is expensive. Here in South Africa, a well known (but expensive) dealer asks R3.70 ($0.49). At the wholesalers I'll get it for half that price. Mind you, the 74LS02 here costs R3.04 ($0.40) per unit, but again, this dealer is very expensive.
 
We've had some problems with some IC's at work. Apparently, some of the people that work in the manufacturing plants will steal the IC's that are bad and supposed to be thrown out. Then they sell them to some no-name distributor.
Sourcing buys them up usually because the part is obsolete and they are scrounging for any that are still on the market.
Then the circuits stop working and we spend a few weeks trying to determine the problem.
 
I was going to name some Big-Name electronics parts stores that sell "sweepings from the manufacture's floor", but eveybody knows who they are. Also their prices are outrageous.
 
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