7812 and 7815 voltage regulators

[atec77]

Trevor Wilson wrote:

"Mr.T" <MrT@home> wrote in message
news:491fd621$0$4449$afc38c87@news.optusnet.com.au...
"atec77" <atec77REMOVE@hotmail.com> wrote in message
news:gfok9l$fqm$1@aioe.org...
he appears to be a long way from most shopping malls
so in the Ozzie tradition making do for now...
That's a good reason of course, but he could have just said so rather than
abuse anyone offering advice.
I'm still not clear why he didn't just download the data sheet though.

**Because he, like atec77, is an ignorant prick. I no longer waste my time
with ignorant pricks. I have better things to do with my time.


Which in truth means

"Having been outed as a self serving wanking spammer twevy got the
shites and hoped by abusing members of the fraternity denying him entry
might divert the stares and accusation about his perverted ways
elsewhere , but it didn't all and sundry saw twevy for the arsewipe he
is . It is no surprise twevy that you failed so miserably in business
and your personal life."
I wish you nothing but discomfort for Christmas and hope the future to
be bleak and foreboding for the few remaining years you have.

 

[atec77]

Trevor Wilson wrote:

"Mr.T" <MrT@home> wrote in message
news:491fd621$0$4449$afc38c87@news.optusnet.com.au...
"atec77" <atec77REMOVE@hotmail.com> wrote in message
news:gfok9l$fqm$1@aioe.org...
he appears to be a long way from most shopping malls
so in the Ozzie tradition making do for now...
That's a good reason of course, but he could have just said so rather than
abuse anyone offering advice.
I'm still not clear why he didn't just download the data sheet though.

**Because he, like atec77, is an ignorant prick. I no longer waste my time
with ignorant pricks. I have better things to do with my time.


Which in truth means

"Having been outed as a self serving wanking spammer twevy got the
shites and hoped by abusing members of the fraternity denying him entry
might divert the stares and accusation about his perverted ways
elsewhere , but it didn't all and sundry saw twevy for the arsewipe he
is . It is no surprise twevy that you failed so miserably in business
and your personal life."
I wish you nothing but discomfort for Christmas and hope the future to
be bleak and foreboding for the few remaining years you have.

 

[ian field]

"mark krawczuk" <krawczuk@adam.com.au> wrote in message
news-6dnRjAP7k74YLUnZ2dnUVZ_q7inZ2d@adnap.net.au...

u a spaz ???? cant you get it thru ya head,,, i dont want to spend 15$
to get a $1.50 ....


and maybe also i want to make do with what i got..

You're obviously an ignorant fuckwit who can't read - I pointed out that a
317 needs 2 resistors so a couple of diodes on a 78xx aren't additional.

 

[kreed]

On Nov 13, 3:28 pm, "K Ludger" <kj...@kljl.org> wrote:

"mark krawczuk" <krawc...@adam.com.au> wrote in message

news:fbSdnXAo84XsM4bUnZ2dnUVZ_oTinZ2d@adnap.net.au...

hi, i want to make  up a 13.8 volt  power supply.

i have some 7812 and 7815 voltage regulators.

would it be best to increase the voltage out of the 7812
or
decrease the voltage from the 7815 ?

how can i do this  ?
thanks,
mark k

Check out the data sheet Mark, you can add a diode or three in the common
leg to ground to "jackup" the regulator. Diode cathode points to ground,
Each diode will add ~0.6V. Try it & see.

If its low current a quick and dirty for the 7815 could be to do the same
only with the diodes in the output, each will drop ~0.6 depending on the
load drawn.

These approached may not be ideal from the regulation point of view but for
a GP supply they should be fine. How much current are you wanting to draw?

-------------------
While it might not matter for your application, I would not suggest
putting diodes in series with the output line
the reason is that the voltage dropped across the diodes will change
with the current drawn through them. (and likely the temperature as
well).

Putting diodes in the ADJ or GND terminal to ground is fine, the
current through them is so small that it isnt going to affect their
voltage. I have never had any problems doing this even with larger
3-5 A regulators.

I do like the idea from Ian Field about running a bias resistor
though.

 

[mark krawczuk]

hey toss pot , you cant read u pedafile , DID I EVER MENTION A 317 IN MY
ORIGINAL POST ... NO YOU POOF..





"ian field" <gangprobing.alien@ntlworld.com> wrote in message
news:yZWTk.46223$%D2.37809@newsfe18.ams2...

"mark krawczuk" <krawczuk@adam.com.au> wrote in message
news-6dnRjAP7k74YLUnZ2dnUVZ_q7inZ2d@adnap.net.au...
u a spaz ???? cant you get it thru ya head,,, i dont want to spend
15$ to get a $1.50 ....


and maybe also i want to make do with what i got..


You're obviously an ignorant fuckwit who can't read - I pointed out that a
317 needs 2 resistors so a couple of diodes on a 78xx aren't additional.

 

[ian field]

"mark krawczuk" <krawczuk@adam.com.au> wrote in message
news:7fSdncHgCNr4d7LUnZ2dnUVZ_o3inZ2d@adnap.net.au...

hey toss pot , you cant read u pedafile , DID I EVER MENTION A 317 IN MY
ORIGINAL POST ... NO YOU POOF..

You're thick as shit.............and then some!!!

 

[mark krawczuk]

is that all u can say you faggot.... you cant answer taht can you ?? i didnt
even mention 317 in my post..
mark k




"ian field" <gangprobing.alien@ntlworld.com> wrote in message
news:JcVXk.5128$io1.1324@newsfe30.ams2...

"mark krawczuk" <krawczuk@adam.com.au> wrote in message
news:7fSdncHgCNr4d7LUnZ2dnUVZ_o3inZ2d@adnap.net.au...
hey toss pot , you cant read u pedafile , DID I EVER MENTION A 317 IN
MY ORIGINAL POST ... NO YOU POOF..


You're thick as shit.............and then some!!!

 

[clanker]

mark krawczuk wrote:

is that all u can say you faggot.... you cant answer taht can you ?? i didnt
even mention 317 in my post..
mark k

Age = 14, IQ = ~60. Let this angry little man go.

 

[Wayne.]

mark krawczuk wrote:

is that all u can say you faggot.... you cant answer taht can you ?? i didnt
even mention 317 in my post..
mark k

Goodness sake!!! Get over yourself. You ask a question, you were
advised of a more appropriate alternative, and you have done nothing but
bitch since.

MAN UP!

 

[ian field]

"Wayne." <abuse@hotmail.com> wrote in message
news:4930a973$0$18618$5a62ac22@per-qv1-newsreader-01.iinet.net.au...

mark krawczuk wrote:
is that all u can say you faggot.... you cant answer taht can you ?? i
didnt even mention 317 in my post..
mark k


Goodness sake!!! Get over yourself. You ask a question, you were advised
of a more appropriate alternative, and you have done nothing but bitch
since.

MAN UP!

I can't understand what he got so hysterical about - all I did was correct
someone who said a 78xx with a couple of offset diodes had a higher
component count, it doesn't because the 317 needs a couple of resistors to
set the voltage.