Isolated, regulated, toroidal step down transformer AC power supply design.

[Bob Parker]

There seems to be a trend to put clear cases on everything these days... Maybe
if you can shine a light through it you can measure its 'transparency'?

Interesting idea, but I think technically knowledgeable people would
see right through it ....

 

[Mark]

I grew tired of this thread a short time ago.

I wouldn't jump to that conclusion hastily. I spent a hell of a long time
tracking down dry joints after the refit. It was a fairly tedious exercise.
Nearly 40 caps were replaced in total, mostly small capacitance
coupling-caps between op-amps.

I've tracked and tracked and tracked it down and I am convinced that it
either ain't where I am looking or that I am not capable of finding it.

Regarding the limits of my intelligence, you haven't pushed near the
envelope yet.

 

[Brian g]

I grew tired of this thread a short time ago.

I am convinced that I am not capable of finding it.




****** Hoo fucking ray!!!!!! At last!!!

Brioan g

 

[Bob Parker]

I grew tired of this thread a short time ago.

I wouldn't jump to that conclusion hastily. I spent a hell of a long time
tracking down dry joints after the refit. It was a fairly tedious exercise.
Nearly 40 caps were replaced in total, mostly small capacitance
coupling-caps between op-amps.

I've tracked and tracked and tracked it down and I am convinced that it
either ain't where I am looking or that I am not capable of finding it.

Regarding the limits of my intelligence, you haven't pushed near the
envelope yet.

Is it possible for you to answer this question with a simple yes or
no? .....

Did this thing have a ridiculous sensitivity to mains voltage
variations *before* you dived into it and started replacing parts?

Just "yes" or "no" is all that's required. Thanks.

 

[Mark]

Some of my assumptions may well have been incorrect, but they are ALL THERE
in the thread and that was ALL I claimed about them.

...but you retorted "No it isn't. You simply spout a whole lot of hogwash in
your thread."

So you can probably understand my frustration (about being asked to repeat
things over and over again) and my futher presumptions that:

a) You didn't read (or understand) the thread. You got it wrong.

b) Having not read (or understood) the thread, decided that I was
"spout[ing] a whole lot of hogwash in [my] thread."

So, you came to a conclusion on a wrong basis. I.E. Having not read or
understood the thread.

I HAVE read the thread. ALL of it. And I know that you have made little
contibution to what has already been written.

Yes, it is a pair of half-wave rectifiers which DOUBLE the voltage. 9 VAC in
and +/-15 VDC out AFTER regulation. Before regulation it MUST be something
less than 18 VDC, but the schematic does not specify this. The diodes look
like Schottkys to me, I haven't replaced them.

I would say that these simple features (9 VAC in, 15 VAC out, after
regulation) qualify the rectifier as a "voltage DOUBLING design". It is in
the SCHEMATIC and I can reproduce it.

I am calling your BLUFF. It is a "voltage DOUBLING design".

Wolf in a sheep's clothing.

 

[Mark]

You are not compelled to treat others with the same respect with which they
treat you, but it is advised in all cases.

However, to surmise what my be your position: "Tell us what WE[1] need to
know or suffer our abuse" does not qualify as just or fair treatment for
anybody.

If you truely believe otherwise, then I think they have a job for you at
Guantanamo Bay. (get it?)

[1] I would like to point out that it is you purports to speak for others,
not me.

I don't really think that IS your position, but it was a very silly thing to
say.

 

[swanny]

Some of my assumptions may well have been incorrect, but they are ALL THERE
in the thread and that was ALL I claimed about them.

..but you retorted "No it isn't. You simply spout a whole lot of hogwash in
your thread."

So you can probably understand my frustration (about being asked to repeat
things over and over again) and my futher presumptions that:

a) You didn't read (or understand) the thread. You got it wrong.

b) Having not read (or understood) the thread, decided that I was
"spout[ing] a whole lot of hogwash in [my] thread."

So, you came to a conclusion on a wrong basis. I.E. Having not read or
understood the thread.

I HAVE read the thread. ALL of it. And I know that you have made little
contibution to what has already been written.

Yes, it is a pair of half-wave rectifiers which DOUBLE the voltage. 9 VAC in
and +/-15 VDC out AFTER regulation. Before regulation it MUST be something
less than 18 VDC, but the schematic does not specify this. The diodes look
like Schottkys to me, I haven't replaced them.

No, it must be more than that or the regulators won't regulate. Once again, you
have no idea what you are talking about.

I would say that these simple features (9 VAC in, 15 VAC out, after
regulation) qualify the rectifier as a "voltage DOUBLING design". It is in
the SCHEMATIC and I can reproduce it.

I am calling your BLUFF. It is a "voltage DOUBLING design".

No it isn't. You don't have a clue. You've said so previously. It's a pair of
half wave rectifiers, one for the +DC rail and one for the -DC rail.

 

[Mark]

Ok, thanks for that link. No, it isn't like mine.

Mine has two extra diodes in the bridge, (four diodes in all) but it ISN'T a
full wave rectifier.

Instead of converting the whole of the input waveform to ONE waveform of
constant polarity, I produces two bi-polar waveforms (+/-) and doubles the
voltage of each of them.

 

[Bob Parker]

Ok, thanks for that link. No, it isn't like mine.

Mine has two extra diodes in the bridge, (four diodes in all) but it ISN'T a
full wave rectifier.

Instead of converting the whole of the input waveform to ONE waveform of
constant polarity, I produces two bi-polar waveforms (+/-) and doubles the
voltage of each of them.

That's right Mark. Keep pretending you can't see my questions
asking if this fault happened after you fiddled with the electronics.
Just keep babbling on about half-wave rectifiers and voltage doublers as
though this is some mysterious problem unrelated to you tearing out all
those naughty horrible-sounding ordinary capacitors and installing the
Backgates you got from Hawaii.
Half-wit.

 

[Mark]

Yeah, OK that's really creative thinking.

I think the UPS solution may be cheaper and easyier. Looking into it.
Thanks.

 

[Mark]

Yeah, someone else suggested the UPS. I think they can be purchased quite
cheaply on EBay. I have no idea how others do it or if they suffer the same
problems.

We live in the far N/E Victoria, just near the NSW boarder and it is the
most notoriously unreliable power supply in the state. I've been told (by
TXU) that we suffer more lighting strikes here than any other part of the
state. We suffer black outs on a weekly basis, occasionally see brownouts
and get voltage over supply almost daily.

 

[Phil Allison]

"Mark"

We live in the far N/E Victoria, just near the NSW boarder

** Might as well just post your address and phone number as tell us that.

How *are* things in beautiful Merbein tonight - really jumpin like usual
?

ROTFL !!!




...... Phil

 

[jasen]

Some of my assumptions may well have been incorrect, but they are ALL THERE
in the thread and that was ALL I claimed about them.

it is but it's all upside down.

how about you select the relevant bits and bring them all together.

 

[Franc Zabkar]

That's right Mark. Keep pretending you can't see my questions
asking if this fault happened after you fiddled with the electronics.
Just keep babbling on about half-wave rectifiers and voltage doublers as
though this is some mysterious problem unrelated to you tearing out all
those naughty horrible-sounding ordinary capacitors and installing the
Backgates you got from Hawaii.
Half-wit.

In my first post to this thread I tried to diplomatically steer the OP
toward first principles in the hope that the penny would drop, but he
clearly has no understanding of the basics. It would have been far
better for him to have acknowledged his ignorance at the outset.
Instead he has chosen to engage in damage control and in so doing has
only dug himself into a deeper hole.

- Franc Zabkar

 

[Mark]

Correction: what *may be your position.

You are not compelled to treat others with the same respect with which
they treat you, but it is advised in all cases.

However, to surmise what my be your position: "Tell us what WE[1] need to
know or suffer our abuse" does not qualify as just or fair treatment for
anybody.

If you truely believe otherwise, then I think they have a job for you at
Guantanamo Bay. (get it?)

[1] I would like to point out that it is you purports to speak for others,
not me.

I don't really think that IS your position, but it was a very silly thing
to say.

Neither are we compelled to answer you civily,


yeah, if that's what is needed, usually it isn't,
as a result such supplies aren't common

Bye.
Jasen

 

[Mark]

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 "

Well, you were 100% wrong about that, Franc. I can even produce the
schematic diagram which proves your statement incorrect.

BUT I DIDN'T RESPOND BY INSULTING YOU, as many others would have done.

And now, it is you who "engage in damage control" by trying to draw
attention away from your error and towards my alleged arrogance.

Unfortunately for you, I have acknowledged my ignorance about electronics
(on this very thread) about 1/2 dozen times PRIOR to your allegation. So,
the allegation doesn't come through the wash.

I don't blame you particularly for engaging in damage control, but it is a
very weak position for you to take. You must be in that second class of
'Phil-o-phile', one who fears him.

 

[Mark]

I can see your questions Bob.

The problem wasn't caused by the recapping, it pre-existed.

It was one of the motivations for recapping the applications power supply.

 

[Mark]

Does anyone else understand this? I don't. Merbein???

 

[Mark]

9 VAC in, 15 VDC out, after regulation.

How is that NOT a voltage DOUBLING design?

Or is it because you believe that such a design is impossible?

It must be one or the other.

Some of my assumptions may well have been incorrect, but they are ALL
THERE
in the thread and that was ALL I claimed about them.

..but you retorted "No it isn't. You simply spout a whole lot of hogwash
in
your thread."

So you can probably understand my frustration (about being asked to
repeat
things over and over again) and my futher presumptions that:

a) You didn't read (or understand) the thread. You got it wrong.

b) Having not read (or understood) the thread, decided that I was
"spout[ing] a whole lot of hogwash in [my] thread."

So, you came to a conclusion on a wrong basis. I.E. Having not read or
understood the thread.

I HAVE read the thread. ALL of it. And I know that you have made little
contibution to what has already been written.

Yes, it is a pair of half-wave rectifiers which DOUBLE the voltage. 9 VAC
in
and +/-15 VDC out AFTER regulation. Before regulation it MUST be
something
less than 18 VDC, but the schematic does not specify this. The diodes
look
like Schottkys to me, I haven't replaced them.

No, it must be more than that or the regulators won't regulate. Once
again, you
have no idea what you are talking about.

I would say that these simple features (9 VAC in, 15 VAC out, after
regulation) qualify the rectifier as a "voltage DOUBLING design". It is
in
the SCHEMATIC and I can reproduce it.

I am calling your BLUFF. It is a "voltage DOUBLING design".

No it isn't. You don't have a clue. You've said so previously. It's a pair
of
half wave rectifiers, one for the +DC rail and one for the -DC rail.

Wolf in a sheep's clothing.

 

[Mark]

With great difficulty.

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