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

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.

b) A design involving transformation to a nominal VAC then rectification and regulation to a nominal DC, filtering and decoupling, and then inversion back to 9 VAC (+/- x%).

But then why bother to make it when you can buy option a) for $30 bucks.

But then again, maybe ONLY a Ferro-resonant UPS design will do it? Probably not.

I did amend my specification to 2 amps (fused at input). The fact of the matter is that I could have scaled up/down most designs that I was likely to receive, except for the very small or the ridiculously large.

Now, where's my nomination? CLUELESS NEWBIE OF THE MONTH seems like a synch to me and you only got two nominations. Phil will vote for me I swear and you just can't get a better credentials than that. Bob will vote for me, twice. Trev will, honest!

[Big snip of my helpful questions that the OP totally ignored]

Well, there's 3 minutes of my life I won't be seeing again...

(YANETUT)

YHGMTPO AE & AUK. YHL. LTBF,YPW.

HTH, HAND.

--
   W  "Some people are alive only because it is illegal to kill them."
 . | ,. w ,      
  \|/  \|/              Perna condita delenda est
---^----^---------------------------------------------------------------

**Oh yeah? See if you can find anyone who disagrees with Bob. Bob has you nailed.

I'll wait.

While I do, go to one of the following newsgroups:

rec.audio.tech sci.electronics.repair

Maybe they'll help you.

--
Trevor Wilson
www.rageaudio.com.au

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.

Oh, OK. So why should I try to deny any allegation of success!

Yup, you got me: This is a successful Troll.

I've fooled you all, *except that wise-old-sage Bob* of course. He saw right through me from the beginning.

Oh, and Phil of course, although I appear to have him turned around, I know he'll come good. He should have trusted his instincts and never budged an inch.

Oh, and you of course. Bob has set you strait.

Yup, you got me so nailed I can't scratch my arse for trying.

Damn! And here I am substituting all those caps with resistors instead! Especially the big caps, with such a small ESR that they can be replaced simply with a wire link ...

Make sure it's silver wire for good acoustic transparency! ;-)

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

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

This one?

Call>> Anything else you wanted to tell me about your expectations?

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.

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 positi>> Poxy, you can not claim that asking a difficult question IS prima

Get back under your bridge, clueless troll.

does that make sense to you?

--

Bye.
   Jasen

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

It makes sense to him but not us. :-(

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

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

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