Isolated, regulated, toroidal step down transformer AC power

Mark wrote:
You said (in what I think was your second post on this thread).

"You are missing the point. There is no way that you can get 15VDC from
a 9.00 VAC rms sine wave using only rectification, filtering and
regulation "
Click to expand...

9.00 VAC RMS * 1.414 (VPeak) = 12.726 Volts, minus the diode drop.
Either the transformer is more than 9.00 VAC, or you aren't getting 15
volts. That is, unless the laws of physics don't apply on your world.




--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
Bob Parker wrote:
Terry Given wrote:

yeah, I second that. I wont buy a cap if I cant get a datasheet for it.
one 10uF cap with 27 Ohms ESR was enough for me. Of course now, thanks
to Bob, I can measure that in a jiffy :)

Cheers
Terry

Thanks Terry. Now I'm thinking about how to make a meter which shows
musicality in capacitors. Maybe do a frequency sweep to see how it
performs at the bass vs midrange vs treble ends of the spectrum? ;-)

Bob
Click to expand...

If you do, you have to release a new version every three or four
months with new features, or better accuracy. ;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
Bob Parker wrote:
On 2/04/2007 05:10 Trevor Wilson wrote:

Here's another couple of places you can ask
your nonsensical question:

sci.electronics.repair
rec.audio.tech

See what responses you receive.

The techs in sci.electronics.repair are a much less bullying lot
than the aggressive riff-raff here.
They're sure to welcome a vague question about an unidentified item
of audiophile equipment, and being lectured about their manners when
they ask for enough information to be able to give any advice. ;-)

Bob
Click to expand...

Yeah, all of them except that Terrell character. Oh, wait that's me!
;-)


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
This one? http://www.tourisminternet.com.au/Yara1.JPG

Calling me a 'Mexican' would be somewhat more traditional.

"Bob Parker" <bobp.deletethis@bluebottle.com> wrote in message
news:46122b16$0$15019$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
On 3/04/2007 20:20 Mark wrote:
Anything else you wanted to tell me about your expectations?

"(You Are Not Expected To Understand This But)

You Have Greatly Misunderstood The Purpose Of Aus.Electronics and Alt
Usenet Kooks. You Have Lost. Learn to Be Funny, You Pathetic Wanker.

Hope This Helps, Have A Nice Day."

I won't bother to make pretensions of 'hip cyber-credibility', except to
say:

TAWSFI, HETLA DETLA YAFLAEIP.

TUTLA EFETLA EEETLA, SRFLA MTFLA ATHFL YAUA!

...and try to sound important whilst doing it.


Get back under your bridge, troll.
Click to expand...
 
I don't think it could be rightly described as a "charge pump" device at
all.

Apparently (because I had to look it up) Charge Pump devices work by
electronically switching the polarity of the capacitors. IE "the capacitor
is disconnected from the original charging voltage and reconnected with its
negative terminal to the original positive charging voltage".

That doesn't happen at all within my application.

I think that the schematic I am looking at is rightly described as a voltage
multiplier.

I.E. it is an "electrical circuit that converts AC electrical power from a
lower voltage to a higher DC voltage by means of capacitors and diodes
combined into a network."

In particular it is a half-wave series multiplier, where the voltage is only
doubled once.

However, voltage multipliers "can be used to generate bias voltages of a few
volts or tens of volts or MILLIONS OF VOLTS"

You said:

" Mark Ilsley = UTTER FUCKING LIAR


Yes, it is a pair of half-wave rectifiers which DOUBLE the voltage. 9 VAC
in and +/-15 VDC out AFTER regulation.
Click to expand...

** Totally impossible bollocks !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

9 volts AC = 12 volts DC *peak* after rectification and filtering."

There is no escape. "Totally impossible" has only ONE meaning.

But I do so love watching you squirm on the end of my hook.

Desperately wracking your brain for an escape, an excuse, an explaination.
ANYTHING to save face. It's fun to observe you in this mode.



"Phil Allison" <philallison@tpg.com.au> wrote in message
news:57974rF2bvg99U1@mid.individual.net...
"swanny"

That's not what you have got. It's what you think you have got.
You have 30VDC out (+/-15VDC).

You have a wall wart transformer with poor load regulation. I'm guessing
it's
about 15VAC you have coming out of your wall wart. I also suspect the
original
design is relying on this to work.


** Nope.

From the copious schizoid ramblings of this delusional bush maggot - I
now surmise the PSU he has operates from a nominal 9 volt AC plug pack
with a couple of amps capacity. One side of the secondary goes directly
to circuit ground.

Then come four diodes and four electros ( values not described) that act
together as " charge pump" voltage multipliers. This will generate maybe
+/- 23 volts DC ( plus ample ripple) at the input to the 7815 / 7915 regs.

Load regulation will be mediocre - at best.

What he ought to do is get a new AC supply tranny ( toroidal is OK) with a
18-0-18 volt secondary of circa 2.5 amps and use a bridge rectifier and
filter electros of say 6,800 uF or a parallel combo to that same sort of
value.

This will have good load regulation and low ripple.

But you will never tell HIM that !!



...... Phil
Click to expand...
 
" Mark Ilsley = UTTER FUCKING PSYCHO LIAR "


I don't think it could be rightly described as a "charge pump" device at
all.
Click to expand...

** Oh yes it can.


Apparently (because I had to look it up) Charge Pump devices work by
electronically switching the polarity of the capacitors. IE "the capacitor
is disconnected from the original charging voltage and reconnected with
its negative terminal to the original positive charging voltage".
Click to expand...

** Exactly what the diodes do when the AC polarity changes.



Yes, it is a pair of half-wave rectifiers which DOUBLE the voltage. 9 VAC
in and +/-15 VDC out AFTER regulation.


** Totally impossible bollocks !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

9 volts AC = 12 volts DC *peak* after rectification and filtering."


There is no escape.
Click to expand...

** For a totally autistic, lying moron like you.





......... Phil
 
Wrong. The laws of physics do apply in OUR world and it certainly is
possible under those laws.

I believe (because I am no expert) that the design I am looking at is
rightly described as a Voltage Multiplier. (read below)

In any case, I wouldn't be quite so adamant about it, if I were you.

Abyway, whilst you are here, why don't we talk about US laws that aren't
applied in Cuba.


"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
news:46136E87.21199544@earthlink.net...
Mark wrote:

You said (in what I think was your second post on this thread).

"You are missing the point. There is no way that you can get 15VDC from
a 9.00 VAC rms sine wave using only rectification, filtering and
regulation "


9.00 VAC RMS * 1.414 (VPeak) = 12.726 Volts, minus the diode drop.
Either the transformer is more than 9.00 VAC, or you aren't getting 15
volts. That is, unless the laws of physics don't apply on your world.




--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
Click to expand...
 
What utter piffle.

I won't be bullied into suppling requests for information. It would be an
act of submission to do so and a reward for the bullies.

I will respond to any polite request for more information with the
information requested, provided it is within the terms of the original
question. I do not feel obliged to answer any questions pertaining to
matters outside those terms or conditions, however I am still FREE to answer
them, if I wish.

Bob ASKED me what I did for a job (and quite politely as I remember it) and
I gave him a very short reply. My family commitments are relevant (to the
question of why I have not been able to peruse a number of other possible
avenues of investigation).

Their have been other reasons given. Caution, inexperience and a lack of
equipment being some of them. You must also consider remote location. I
can't just duck around the corner and pick up whatever I may need.

I had a look under the 'bonnet' last night and the regulator ICs are lying
flat on the PCB closely surrounded by many capacitors. The risk of shorting
the pins with the DMM probes is perilous. I need to pick up a set of mini
alligator clips to do the measurements safely. Attaching them when the power
is OFF. At the moment that means waiting until after the Easter break.

I really expect no further help from you, Poxy. And I am untroubled by my
position.

"Poxy" <pox@poxmail.com> wrote in message news:46104cd3@dnews.tpgi.com.au...
Mark wrote:
Poxy, you can not claim that asking a difficult question IS prima
facie a claim of expertise by the person posing the question. That
appears to be the edifice of your argument and it isn't true.

I apologise for assuming you had some level of competence and experience
with electronics. I clearly misjudged you initially.

However, what I can tell now after reading these inumerable posts
containing
so little information about your alleged "device" and so much sbout
yourself
and your opinions is that whether you know it or not, you're a troll. I
don't think your motivations nor intentions in going on this way are to
solve whatever problem you might have, it's to cause conflict and grief.

I doubt whether this "device" actually exists, or whether it's a construct
of experiences and things you've read, as when put together none of it
makes
sense and you are unable to come up with a cogent explanation.

In a similar way, I doubt all this business about your family - it's such
an
irrelevant thing to bring into a discussion about a technical issue - it
sounds like another fabrication you've made up and thrown in just to cause
conflict and confusion.

I don't quite get what it is you find so attractive about trolling, but I
do
regret being sucked in and trying to offer help.






Difficult questions aren't always difficult to postulate. Sometimes
they are very simple. For example, the square root of minus one has
no real solution but it isn't difficult to postulate.

If I've asked a difficult question it is entirely accidental. If I've
acted with belligerence, it was entirely in defending MYSELF and not
my IGNORANCE.

People have value WHETHER OR NOT they know anything about
electronics. I had a right to defend my self respect and I exercised
that right and I still do, against anyone that would seek to take it
away from me.

There has been precious little help and a hell of a lot of
humiliation. And that's the truth about it.

Piffle to your top-posting argument.

Top posting + asking for help + not suppling all requests for more
information <> arrogance.

Top posting is a matter of style.

Asking for help is sometimes necessary and at other times, unwise.

Suppling ALL requests for information is:

a) Sometimes not possible.
b) Not always timely or practical (equipment and expertise).
c) Not something you should EVER allow yourself to be BULLIED into.

The more you bludgeon the more resolutely I resist. Why?

People have value WHETHER OR NOT they know anything about electronics.

How can you NOT see that?

"Poxy" <pox@poxmail.com> wrote in message
news:460f65ff@dnews.tpgi.com.au...
Mark wrote:

'Difficult' questions might be asked out of pure ignorance. In fact,
'difficult' questions might be asked for any reason what-so-ever.
If a question poses a difficult answer, it would be pure folly to
make ASSUMPTIONS about the expertise of the person putting the
question.

You have purposely supplied so incredibly little information that
we've had
to make the best assumptions we could in an attempt to help. Even
when told
what you're asking is complex, impractical and most likely not
required, you've responded in such a dismissive manner that one
could only assume you
must have a clue what you're talking about.

Interestingly, the only person who immediately picked you for what
you are is Phil - I'm not the biggest fan of Phil's choice of
interpersonal manner sometimes, but he did work you out in an
accurate and timely fashion.

As to your suggestion that 'top-posting' is arrogant, that
presupposes that top-posting amounts to a pretension of superior
importance. I regard it as a subjective judgement of style. I
honestly have no objection to any particular topography of posting
and do not make assumptions about a persons pretentions based on it.

No, top posting in a forum where bottom posting is the convention
*AND* asking for help *AND* ignoring repeated requests to not top
post is arrogant
and rude, as is your general manner.

Rather, such persistent objections to any particular topography of
posting are childish in the extreme. You might just as well say "I
don't like you because you're wearing green today"

No, because you are being rude and inconsiderate towards the people
*YOU ARE
ASKING FOR HELP*.

Phil-O-phile's are a community, not a conspiracy. Nor are they
entirely composed of "dysfunctional sociopaths" and I have already
made this distinction perfectly clear (maybe about 3 times
already!).
Click to expand...
 
Yeah, right. Or to paraphrase your own comments:

"Hey, just because we behaved like arrogant cunts, don't expect any better
treatment elsewhere"

which is roughly to say: "Usenet is our life, and we can follow you
anywhere"


"Bob Parker" <bobp.deletethis@bluebottle.com> wrote in message
news:4610bed7$0$15004$5a62ac22@per-qv1-newsreader-01.iinet.net.au...
On 2/04/2007 05:10 Trevor Wilson wrote:

Here's another couple of places you can ask
your nonsensical question:

sci.electronics.repair
rec.audio.tech

See what responses you receive.


The techs in sci.electronics.repair are a much less bullying lot than
the aggressive riff-raff here.
They're sure to welcome a vague question about an unidentified item of
audiophile equipment, and being lectured about their manners when they ask
for enough information to be able to give any advice. ;-)


Bob
Click to expand...
 
On 5/04/2007 13:12 Mark wrote:
But I do so love watching you squirm on the end of my hook.

Desperately wracking your brain for an escape, an excuse, an explaination.
ANYTHING to save face. It's fun to observe you in this mode.
Click to expand...
Go and irritate the hell out of some other newsgroup will you, troll?
It's bad enough having all the 'net kooks' crossposting their stuff
into aus.electronics without you making it even worse.
 
On 5/04/2007 15:13 Mark wrote:
Yeah, right. Or to paraphrase your own comments:

"Hey, just because we behaved like arrogant cunts, don't expect any better
treatment elsewhere"

which is roughly to say: "Usenet is our life, and we can follow you
anywhere"
Click to expand...
Go and annoy some other group with your babble, troll. We're tired
of you being here.
 
On 5/04/2007 13:45 Phil Allison wrote:
" Mark Ilsley = UTTER FUCKING PSYCHO LIAR "


I don't think it could be rightly described as a "charge pump" device at
all.


** Oh yes it can.


Apparently (because I had to look it up) Charge Pump devices work by
electronically switching the polarity of the capacitors. IE "the capacitor
is disconnected from the original charging voltage and reconnected with
its negative terminal to the original positive charging voltage".


** Exactly what the diodes do when the AC polarity changes.



Yes, it is a pair of half-wave rectifiers which DOUBLE the voltage. 9 VAC
in and +/-15 VDC out AFTER regulation.

** Totally impossible bollocks !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

9 volts AC = 12 volts DC *peak* after rectification and filtering."


There is no escape.


** For a totally autistic, lying moron like you.

........ Phil
Click to expand...

This troll doesn't have a clue about even basic electronics. No
point trying to explain anything to him.
All he does is make a (bigger) fool of himself by automatically
contradicting whatever you say, claiming that he knows more than you do
and claiming to have you on his hook, to provoke more responses. Sorta
like the Monty Python 'Argument' sketch.
He's a stock-standard newsgroup troll. He doesn't have a life so he
gets on here for recreation and entertainment.


Bob
 
Mark wrote:
I don't think it could be rightly described as a "charge pump" device at
all.

Apparently (because I had to look it up) Charge Pump devices work by
electronically switching the polarity of the capacitors. IE "the capacitor
is disconnected from the original charging voltage and reconnected with its
negative terminal to the original positive charging voltage".

That doesn't happen at all within my application.

I think that the schematic I am looking at is rightly described as a voltage
multiplier.

I.E. it is an "electrical circuit that converts AC electrical power from a
lower voltage to a higher DC voltage by means of capacitors and diodes
combined into a network."

In particular it is a half-wave series multiplier, where the voltage is only
doubled once.

However, voltage multipliers "can be used to generate bias voltages of a few
volts or tens of volts or MILLIONS OF VOLTS"
Click to expand...
I've not seen this method described used to generate a bipolar supply from a
single AC source before. Do you have a schematic or photo of the PCB that would
allow further examination?
 
On 2007-04-01, Mark <marknospampleaseilsley@dodo.com.au> wrote:
With great difficulty.

However, it is a problem with the thread structure of most readers, not with
the order of my statements.
Click to expand...
does that make sense to you?

--

Bye.
Jasen
 
On 7/04/2007 13:32 jasen wrote:
On 2007-04-01, Mark <marknospampleaseilsley@dodo.com.au> wrote:
With great difficulty.

However, it is a problem with the thread structure of most readers, not with
the order of my statements.

does that make sense to you?
Click to expand...

It's the same 'Mark logic' which has applied to all his other postings.

It makes sense to him but not us. :-(
 
That's not what you have got. It's what you think you have got.
You have 30VDC out (+/-15VDC).

You have a wall wart transformer with poor load regulation. I'm guessing it's
about 15VAC you have coming out of your wall wart. I also suspect the original
design is relying on this to work.

Try taking some measurements rather than quoting the info that's printed on it.
Click to expand...
Mark said he had 4 diodes in the rectifier, that's not a normal doubler.
or rather that's two doublers one going up and one going down.

Bye.
Jasen
 
On 2007-04-02, Mark <marknospampleaseilsley@dodo.com.au> wrote:
What was wrong with either of these suggestions?

a) Buy another UPS (on Ebay for around $30) and then just step-down the
voltage using my pre-existing wall-wart transformer. If 240 VAC goes in,
something CLOSE to 9 VAC should come out and everything is happy, ..maybe.
Click to expand...
good luck finding an online, sine wave, UPS for that price.

A $30 UPS is likely to be modified square wave, and offline, and it'll be
exactly useless for your purpose.

Bye.
Jasen
 
On 7/04/2007 15:21 jasen wrote:
On 2007-04-02, Mark <marknospampleaseilsley@dodo.com.au> wrote:
What was wrong with either of these suggestions?

a) Buy another UPS (on Ebay for around $30) and then just step-down the
voltage using my pre-existing wall-wart transformer. If 240 VAC goes in,
something CLOSE to 9 VAC should come out and everything is happy, ..maybe.

good luck finding an online, sine wave, UPS for that price.

A $30 UPS is likely to be modified square wave, and offline, and it'll be
exactly useless for your purpose.

Bye.
Jasen
Click to expand...

I thought of telling him that, but I knew he'd disagree because it
wasn't what he wanted to hear, so I didn't.

Bob
 
Which description method would that be? "Charge Pump" or "Voltage
Multipliers".

These devices are commonly classed as Voltage Multipliers.

The specific voltage multiplier I am looking at is a Half-wave Voltage
Doubler, or more accurately, two of them.

Here is a schematic of a "Half-wave Voltage Doubler"
http://tpub.com/neets/book7/0294.GIF

Here is the general description of Voltage Multipliers from the Electrical
Engineering Training series: http://tpub.com/neets/book7/27m.htm

My device is not like the "Full-wave voltage doubler" described in Fig 4-49
because it produces two output voltages (+/- 15VDC). So two halves do not
make a whole, in this case.

It is TWO Half-wave Voltage Doublers. I have Emailed the schematic to
gswan3@bigpond.com.au in pdf format. I can't think of any easy way to
publish it here. Enjoy the Spam.

p.s. What does a wolf in sheep's clothing do over the Easter break?


"swanny" <blahgswan3blah@blahbigpondblah.comblah.blahau> wrote in message
news:GG5Rh.9703$M.59@news-server.bigpond.net.au...
Mark wrote:
I don't think it could be rightly described as a "charge pump" device at
all.

Apparently (because I had to look it up) Charge Pump devices work by
electronically switching the polarity of the capacitors. IE "the
capacitor
is disconnected from the original charging voltage and reconnected with
its
negative terminal to the original positive charging voltage".

That doesn't happen at all within my application.

I think that the schematic I am looking at is rightly described as a
voltage
multiplier.

I.E. it is an "electrical circuit that converts AC electrical power from
a
lower voltage to a higher DC voltage by means of capacitors and diodes
combined into a network."

In particular it is a half-wave series multiplier, where the voltage is
only
doubled once.

However, voltage multipliers "can be used to generate bias voltages of a
few
volts or tens of volts or MILLIONS OF VOLTS"


I've not seen this method described used to generate a bipolar supply from
a
single AC source before. Do you have a schematic or photo of the PCB that
would
allow further examination?
Click to expand...
 
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