From: "Werner"
Newsgroups: sci.electronics.basics,sci.electronics.components,sci.electronics.design,sci.electronics.equipment,sci.electronics.misc
References: <5lQJ9.1476$jM5.4170@newsfeeds.bigpond.com>
Subject: Re: Bad LM338K?
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Date: Thu, 12 Dec 2002 09:25:02 GMT
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NNTP-Posting-Date: Thu, 12 Dec 2002 10:25:02 MET
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I've bought my LM338 at the regular electronics store ... the device works
fine for loads under 0.5 amps ... but around 0.8 Amps it drops the output
voltage under the voltages I've set with a minimal load of 30 mAmps at the
LM's output ....
The cooling element is fine, in fact, the LM does not even provide the
desired output and the output voltage drops as soon as the 1 Amp load is
applied ... feeling the LM housing after a few seconds run, is only warm
(not hot) ... all the time the input to the LM stays very stable, as I've
used a very heavy duty transformer (10 Amps rating) ...
"Phil Allison" wrote in message
news:5lQJ9.1476$jM5.4170@newsfeeds.bigpond.com...
>
> "Werner" wrote in message
> news:udMJ9.46530$Ti2.7149@afrodite.telenet-ops.be...
> > Hi guys,
> >
> > I'm looking for a answer to a puzzling question ...
> >
> > I've build a power supply from a LM338K (TO3) with a 10.000 uF and a
100uF
> > capacitor on the input line and a 1uF and a 0.1uF capacitor to output a
> > fixed 24 volts DC supply.
>
>
> ** The LM338K may be faulty or even a fake - where did you get it ?
>
>
>
> .................... Phil
>
>
>