9V 1A schematic needed

[Fred Bloggs]

DaveM wrote:

LMFAO!!

What's really laughable is how you similarly stupid people can
understand each other so well- sort of like pedophiles and other
sociopathic deviants, you all know each other instinctively. Someone
with your posting history is no position to laugh at anything. You are
right about one thing, you are a "F"ing"A".

 

[Roger Lascelles]

"John Woodgate" <jmw@jmwa.demon.contraspam.yuk> wrote in message
news:+vZqtVBIt9OCFw3u@jmwa.demon.co.uk...

I read in sci.electronics.design that Mac <foo@bar.net> wrote (in
pan.2005.03.19.07.11.50.951783@bar.net&gt about '9V 1A schematic
needed', on Sat, 19 Mar 2005:

In fact, the overall efficiency, measured as Idc/Irms, is higher at low
rectifier conduction angles, even though the peak diode current is
higher. A large filter capacitor doesn't increase transformer heating.
--

My simulations slow a slight increase in RMS current when moving from a
lowish capacitor to a very large one, with load DC current held constant.
The increase is perhaps 10% with typical small transformer supplies. So you
have some extra heating, not precisely zero, but close enough.

However, this is different to efficiency, which is what you are talking
about.

The point is that transformer winding resistance and leakage inductance are
quite dominant in determining RMS current. Because these factors are
invisible on the schematic, I think people start to think of peak currents
climbing ever upwards.

The other thing is that you get diminishing returns on trying to drag up
that marginally low voltage by increasing the capacitor !

I know a guy who used to make audio mixers etc, and he used low resistance,
low leakage inductance toroid transformers - then added resistance to
stretch the conduction angle to reduce hum. Perhaps the longer conduction
pulse had fewer of those more audible harmonics.

Roger Lascelles

 

[John Fields]

On Sat, 19 Mar 2005 05:56:58 GMT, "J-vibe" <nospam@nospam.com> wrote:

It's amazing how moronic & pathetic some people can be. Don't be upset at me
for your failure to understand my question.

---
You should realize that it was your original badly-formulated question
which started the whole thing and take responsibility for it instead
of trying to make yourself appear blameless. A transformer _isn't_
what you're looking for, what you want is called a power supply.

But, even if that's what you had in mind and merely called it the
wrong thing, your question was vague in that the performance
requirements of the power supply weren't defined. While we could
guess that what you really wanted was a power supply, we can't reply
sensibly unless you tell us what you want/need. For instance, even at
this late stage in the game you haven't given us an inkling as to
whether or not you need the supply to provide a regulated output and
if you _do_ need it to be regulated, how well. Nor have you specified
the dimensions into which you want the thing to fit. "As small as
possible" to you may mean a one inch cube, while to anyone else it may
mean something entirely different.

Finally, this is sci.electronics.design and, while most of us here
will field basic questions, the proper venue for yours would be
sci.electronics.basics, where (no offense intended) there are no
stupid questions and newbies are treated, generally, very nicely if
they behave themselves.

--
John Fields

 

[John Woodgate]

I read in sci.electronics.design that Roger Lascelles
<invalidl@invalid.invalid> wrote (in <3a29ijF67fp9mU1@individual.net&gt
about '9V 1A schematic needed', on Sat, 19 Mar 2005:

"John Woodgate" <jmw@jmwa.demon.contraspam.yuk> wrote in message
news:+vZqtVBIt9OCFw3u@jmwa.demon.co.uk...
I read in sci.electronics.design that Mac <foo@bar.net> wrote (in
pan.2005.03.19.07.11.50.951783@bar.net&gt about '9V 1A schematic
needed', on Sat, 19 Mar 2005:

In fact, the overall efficiency, measured as Idc/Irms, is higher at low
rectifier conduction angles, even though the peak diode current is
higher. A large filter capacitor doesn't increase transformer heating.
--

My simulations slow a slight increase in RMS current when moving from a
lowish capacitor to a very large one, with load DC current held constant.
The increase is perhaps 10% with typical small transformer supplies. So you
have some extra heating, not precisely zero, but close enough.

I based my statement on theoretical calculations, so simulations may
provide somewhat different results.

However, this is different to efficiency, which is what you are talking
about.

The point is that transformer winding resistance and leakage inductance are
quite dominant in determining RMS current. Because these factors are
invisible on the schematic, I think people start to think of peak currents
climbing ever upwards.

Agreed. Do you find that leakage inductance has a significant effect?

The other thing is that you get diminishing returns on trying to drag up
that marginally low voltage by increasing the capacitor !

A real mug's game, that is! 1 volt per farad, or thereabouts.

I know a guy who used to make audio mixers etc, and he used low resistance,
low leakage inductance toroid transformers - then added resistance to
stretch the conduction angle to reduce hum. Perhaps the longer conduction
pulse had fewer of those more audible harmonics.

Yes, it does. I've done a lot of analysis of these circuits in

connection with the famous IEC/EN 61000-3-2 standard on mains harmonic
emissions.
--
Regards, John Woodgate, OOO - Own Opinions Only.
There are two sides to every question, except
'What is a Moebius strip?'
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk

 

[Larry Brasfield]

This has been converted, via a process I will call the DERF transform [1].
This elision process conforms to accepted Usenet quoting practise with
the exception that elided text is replaced by "[DERF]" and, where needed
for grammaticality, short sequences within a '[]' pair are inserted.

[1. Application of a filter removing Dreck, Extraneousness, Redundancy, Foolishness.]

"Fred Bloggs" <nospam@nospam.com> wrote in
message news:423BEDE7.8060207@nospam.com...

[DERF]

where are all the words on the noise induced detection problem in the 40khz amplifier thread?

I'm not sure what words you refer to. Can you clarify?

now you are be called on it- You just don't seem to be taking up the challenge,
(That was not English before the DERF transform either.)

If by 'called on it' you refer to your 3 posts several hours
ago, I have not read them yet. I've always been the sort
to save my favorite parts of a meal until last. However, if
you have elected to actually engage in technical argument,
I eagerly anticipate both the "challenge" <g> and the result.
However, from the volume reduction here effected by the
DERF transform, I suspect that you have not undergone
enough of a personality transformation to actually get to
the technical merits with me. "We" shall see shortly.

[DERF]
--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Larry Brasfield]

"John Woodgate" <jmw@jmwa.demon.contraspam.yuk> wrote
in message news:+vZqtVBIt9OCFw3u@jmwa.demon.co.uk...

I read in sci.electronics.design that Mac <foo@bar.net> wrote (in
pan.2005.03.19.07.11.50.951783@bar.net&gt about '9V 1A schematic
needed', on Sat, 19 Mar 2005:

Choosing capacitor values is a bit tricky, too. The bigger they are, the
more they force the transformer into a low duty-cycle, high-current mode
of operation.

In fact, the overall efficiency, measured as Idc/Irms, is higher at low
rectifier conduction angles, even though the peak diode current is
higher. A large filter capacitor doesn't increase transformer heating.

That statement really makes no sense to me.
How can you crowd the same charge transfer
into less time and get its RMS value to decrease?
(For conceptual simplification, assume the DC
current taken from the bridge is constant, so that
the charge, (Idc * (2 f)), is held constant.

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Larry Brasfield]

(Minor correction inserted in place below.)
"Larry Brasfield" <donotspam_larry_brasfield@hotmail.com> wrote
in message news:QUX_d.14$te2.382@news.uswest.net...

"John Woodgate" <jmw@jmwa.demon.contraspam.yuk> wrote
in message news:+vZqtVBIt9OCFw3u@jmwa.demon.co.uk...
I read in sci.electronics.design that Mac <foo@bar.net> wrote (in
pan.2005.03.19.07.11.50.951783@bar.net&gt about '9V 1A schematic
needed', on Sat, 19 Mar 2005:

Choosing capacitor values is a bit tricky, too. The bigger they are, the
more they force the transformer into a low duty-cycle, high-current mode
of operation.

In fact, the overall efficiency, measured as Idc/Irms, is higher at low
rectifier conduction angles, even though the peak diode current is
higher. A large filter capacitor doesn't increase transformer heating.

That statement really makes no sense to me.
How can you crowd the same charge transfer
into less time and get its RMS value to decrease?
(For conceptual simplification, assume the DC
current taken from the bridge is constant, so that
the charge, (Idc / fc), is held constant.

(Where 'fc' is 2 * line_frequency for a full-wave bridge,
or 1 * line_frequency for a half-wave bridge.)

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Fred Bloggs]

Larry Brasfield wrote:

.
....

Oh tee-hee-hee-heee. hey look at how clever Laweee Brathfeld is every
body- [ yell that with lisp and childish voice....]

Where's your workup on the 40kHz amplifier thread, fairy loudmouth boy?
Can't go any further with 4KTRB and some other simple-minded trash? We
are not surprised, windbag. You are one little superficial and worthless
moron.

 

[Fred Bloggs]

Larry Brasfield wrote:

That statement really makes no sense to me.
How can you crowd the same charge transfer
into less time and get its RMS value to decrease?
(For conceptual simplification, assume the DC
current taken from the bridge is constant, so that
the charge, (Idc * (2 f)), is held constant.

Ooooh- deep, deep, question, superficial little piss ant boy and
pretentious moron...Where's your workup on the 40kHz amplifier thread,
fairy loudmouth boy? Can't go any further with 4KTRB and some other
simple-minded trash? We are not surprised, windbag. You are one little
superficial and worthless moron.

 

[Fred Bloggs]

Larry Brasfield wrote:

the charge, (Idc / fc), is held constant.
(Where 'fc' is 2 * line_frequency for a full-wave bridge,
or 1 * line_frequency for a half-wave bridge.)

Did ya' figure that out, retard? Where's your workup on the 40kHz
amplifier thread, fairy loudmouth boy? Can't go any further with 4KTRB
and some other simple-minded trash? We are not surprised, windbag. You
are one little superficial and worthless moron.

 

[Larry Brasfield]

The DERF tranform, applied here, is described earlier in this thread.

"Fred Bloggs" <nospam@nospam.com> wrote in
message news:423C5287.6090503@nospam.com...

Larry Brasfield wrote:
[DERF]
Where's your workup on the 40kHz amplifier thread [DERF]?

See my post at 12:10 on March 18.

?

I explained that already. See my post at 7:19 on March 19.

[DERF]
--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Fred Bloggs]

Larry Brasfield wrote:

I explained that already. See my post at 7:19 on March 19.

Your explanation is unacceptable- it is a rodent dodge, something I'm
damned sure you have puuuuuuuulllenty of practice with. You're dropping
it because you no way in hell can go any further- you have nothing left.
Anymore who expends 500 words on a bs 4KTRB answer is a total fraud.
Looks like you're crumbling, windbag- there's just nothing there.

 

[J-vibe]

Fred,
I've been told about your posts and how you love to answer with really
stupid responses.
So I guess I'm also now privileged with your child-like "Daddy! look at me!,
look at me!" lack of attention.
I feel special now! I do have a sense of humor...
Got to love that those legs of yours, ever thought of modeling for Sheer
Nylons?
http://www.dooyoo.co.uk/archive-lifestyle/my-experience-of-varicose-veins/301495/
Fred, just put a lid on it.... I came here to learn electronics. If I wanted
jokes, I'd go to
rec.jokes

"Fred Bloggs" <nospam@nospam.com> wrote in message
news:423BEC75.9010705@nospam.com...

DaveM wrote:
"Fred Bloggs" <nospam@nospam.com> wrote in message
news:423B861A.7090909@nospam.com...


Larry Brasfield wrote:


Does anyone have a 9V 1A transformer schematic? I want to
integrate it into a project to run a disk drive. The smaller
the better.



The usual procedure, assuming you are using a CAD tool, is to
pull a generic transformer symbol from the library already
available with every such tool I've seen, then edit some fields
on it to state its output value and current rating.

Damn you're dumber than a rock- no clue in hell what the OP was
talking about...



LMAO!!!! Larry gave a very direct answer to the OP's question. He
specifically asked for a schematic for a transformer. It was all
very tongue-in-cheek. I thought about giving a very similar answer
but Larry beat me to it.

Looks like you're the one behind the curve. You seem to miss the point
that his answer was of about the same characteristic relevance as all
his other posts- he is a totally clueless nitwit, and any attempt at
humor would be swamped by the overwhelming hot air, pretense,
pseudo-theoretical factoid trash, and other elements of his style.

 

[Larry Brasfield]

This has been converted, via a process I will call the DERF transform [1].
This elision process conforms to accepted Usenet quoting practise with
the exception that elided text is replaced by "[DERF]" and, where needed
for grammaticality, short sequences with a '[]' pair are inserted.

[1. Application of a filter removing Dreck, Extraneousness, Redundancy, Foolishness.]

"Fred Bloggs" <nospam@nospam.com> wrote in
message news:423C535E.409@nospam.com...

Larry Brasfield wrote:

That statement really makes no sense to me.
How can you crowd the same charge transfer
into less time and get its RMS value to decrease?
(For conceptual simplification, assume the DC
current taken from the bridge is constant, so that
the charge, (Idc * (2 f)), is held constant.

[DERF]
(I am tempted to refine the DERF notation so that
ridiculous amounts cut repetition are indicated.)

Fred, you need help. Or your meds. Or both.
Settle down and try to remember how it was
to resemble a normal person, if you can.

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Larry Brasfield]

The DERF tranform, applied here, is described earlier in this thread.

"Fred Bloggs" <nospam@nospam.com> wrote in
message news:423C57BE.9040205@nospam.com...

Larry Brasfield wrote:
I explained that already. See my post at 7:19 on March 19.

Your explanation is unacceptable-
[DERF]
You're dropping it because ...

No, Fred, I am not dropping it all. As anyone with
the brains God gave turnips can see, you are not
responding to it except with garbage removed by
the DERF transform. Do you truly find it so hard
to devise a rational argument, or do you see your
role here as mere pontification? Do you imagine
that your garbage injections here do anything but
make you ever more obviously a fool?

[DERF]

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Larry Brasfield]

"J-vibe" <nospam@nospam.com> wrote in message
news:W2Z_d.14608$cN6.9357@newsread1.news.pas.earthlink.net...

Fred,
I've been told about your posts and how you love to answer with really
stupid responses.
So I guess I'm also now privileged with your child-like "Daddy! look at me!,
look at me!" lack of attention.
I feel special now! I do have a sense of humor...

I hope this means you fully recovered from whatever
shock you suffered on account of my application of
the inverse-DERF transform to what would have been
empty text otherwise. I would like to know that, with
a little research, you were able to discern its meaning.

Please drop me a line by email if you would like any
further clarification, mitigation, or a real apology.

[Frivolity cut.]

"Fred Bloggs" <nospam@nospam.com> wrote in message
news:423BEC75.9010705@nospam.com...
[Off-point old quotes cut.]

[Fred-dreck cut.]

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Fred Bloggs]

J-vibe wrote:

Fred,
I've been told about your posts and how you love to answer with really
stupid responses.

And you believe everything you're told?

So I guess I'm also now privileged with your child-like "Daddy! look at me!,
look at me!" lack of attention.
I feel special now! I do have a sense of humor...

He's the deal, you worthless little SHIT AND PUKE- GO FUCK YOURSELF-
TAKE YOUR ASININE TRASH QUESTION TO BASIC- IT DOESN'T EVEN RATE THAT-
YOU ARE A WISE-ASS LITTLE MORON PUNK- AND THAT IS A FACT....

"J_VIBE" HUH- THAT SOUNDS SO COOL-!!! OOOHHH-HOOO-HOOO. I HOPE YOU LIKE
THE IDEA OF WORKING IN A KITCHEN....

 

[Fred Bloggs]

Larry Brasfield wrote:

Please drop me a line by email if you would like any
further clarification, mitigation, or a real apology.

What's the matter pseudo-intellectual, afraid to have your bullshit
scrutinized in public? You are already following the chickenshit
pattern- the little worms who claim they are being attacked and send
little anonymous bullshit emails around....invariably worthless garbage.

 

[Fred Bloggs]

John Larkin wrote:

So don't pay him undue attention: he's not nice and he's not
important.

As far as you'll ever know this is true- I have you and many other
ego-trash regulars on virtual plonk-and will *NEVER* answer any of your
questions. You need to get a clue and ask why the transactions on NG are
so low-brained. and low-class, then figure the answer has a lot to do
with people like you, narcissists, frauds, and braggarts.

 

[Fred Bloggs]

Larry Brasfield wrote:

No, Fred, I am not dropping it all.

You haven't done a f_ucking thing, pseudo-intellectual- you stopped
short because you're a f_ucking phony piece of loudmouthed trash-
spewing a bunch of 4ktrb trash. What is clear is that you are a sorry
assed sack of shit NG troll.