John Curl's Blowtorch preamplifier part II

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I support attempts to write accurate technical english on a technical Forum.
Otherwise we are left guessing at what ambiguous statements might mean.

Spelling errors can be excused, lack of english due to being a non native language is excused.
gobble de gook written to save time can never be excused.

I believe that "gobbledegook" is the proper usage and spelling. ;)
 
Andrew,
It makes it much easier if you add the comma to the numbers when they get that large such as 100,000 or 100K would also be fairly universal. Hrs is fairly standard as far as I know for hours. Otherwise I don't see any problem with any of the ways you posted.
I used to use the comma separator to divide the thousands and make for easier legibility
But my EU neighbours use the comma as the decimal place, even though they are in an english technical language Forum.

It seems that avoiding the separator will help with unambguous typing until we get all our Members to use the stop (.) as the decimal place.

How do you read:
1.000Vdc
1,000Vdc
1,000,00Vdc
100,000.0Vdc
0.1Vdc
0,1Vdc
,1Vdc
.1Vdc

that list has some ambiguity as long as we have to tolerate the EU convention of using the comma decimal place on our Forum.

Do you see why I felt the need to change from my former practice of correctly using the comma (,) separator for easier legibility, in this english language Forum?
 
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I believe that "gobbledegook" is the proper usage and spelling. ;)
I tell myself that I can't spell, now you have proved it. And everyone knows my grammer is near non existant. But when Members take the time to inform me, I try to take the advice on board.

Unfortunately, my Browswer has stopped spellchecking after I did an update after an invite to speed up Firefox, even though it appears to be turned on. I have checked twice.

Find other links to parliamo Glasgow
https://www.youtube.com/watch?v=0fw_2waRx7s

concatenating the words in the translation makes the reading nearly impossible.
Maybe I had that in mind when I separated out the "de"?
 
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in bias operation the LED can be operated way below the rated current that the nominal life is given for

Exactly what a HD/ER diesel engine is, a pinched/squeezed/quenched version of the standard model.

(call me a pathetic bean counter soab, for non-politicians, 'most of the time' is way over 50%. My attorney advised me to make a public announcement : any resemblance to legal/illegal persons or statements of a political nature, is purely a figment of your imagination.)
 
www.hifisonix.com
Joined 2003
Paid Member
"I have to start getting used to adressing you as Mr. Mr. Russell, Mr. Russell."

9.5 years in Asia, (Tokyo, Taipei, Shanghai) back in Europe now. Hustle and bustle of Shanghai on Sunday and today I took a walk in a beautiful forest. Awesome!

I consider myself very lucky to have experienced what I did career wise.

My equipment will arrive in about 5 weeks, my wife will be sent out to do some shopping and I am going to wind it up. Apparently the 703's can take 200 watts.

:D

__________________
Hasi bo best
 
The Blowtorch that was recently pictured was so 'pretty', even 'shiny', that I did not recognize it. For the record, we didn't add any led's to the CTC Blowtorch, because they would add something extra that is NOT really necessary for the function it was intended for. I do use led's in the Parasound JC-2 and many other designs.
 
diyAudio Member RIP
Joined 2005
reverse currents

That's illuminating <ducks>.

The first time I have seen an absolute maximum reverse current spec. One wonders if that is a degradation mechanism similar to the effect of reverse breakdown on base-emitter junctions, which is well-known to degrade beta.

In that other forum years ago a couple of us took issue with the operation of a very sensitive soul's "optical compressor" as being questionable, as the guy had a 100nF driving the LED of an optocoupler --- and nothing else. PRR stepped in and chided us for our failure to see that the designer was counting on the reverse breakdown of the LED to pass currents of both polarities. Indeed that was how it managed to work, but I maintained that the breakdown voltage was not an even-remotely-guaranteed spec. I even measured a bunch of LEDs, and contacted the manufacturer of the opto about it, receiving a stony silence.

So maybe the design was something that needed an extended "break-in" :rolleyes:

But so far, all of this data about light output aging has not touched on the association, or perhaps the lack of it, with forward-biased I-V curves and noise. I haven't looked too hard, but searches for such are not yielding much of anything.
 
But so far, all of this data about light output aging has not touched on the association, or perhaps the lack of it, with forward-biased I-V curves and noise. I haven't looked too hard, but searches for such are not yielding much of anything.

There is extensive literature in using LED's for medical devices. Those SPO2 finger clips use RED and IR pulsed at very high peak current. I have found 1/f and popcorn noise in the optical output. Don't fool yourself the medicos use the cheapest stuff they can find, I have stories.

This one has useful data... http://www.researchgate.net/profile...ing_diodes/links/54bcea0f0cf29e0cb04c55e3.pdf

EDIT - This paper is available for free but now my link points to the one the company pays for.
 
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