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Bob Engelhardt <BobEngelhardt@comcast.net>: Jan 05 04:03PM -0500 On 1/5/2017 1:04 PM, Jeff Liebermann wrote: ... > DLG600 is rated at 90V/25A, while the TIP32C at 100V/3A. That would > seem to be a rather poor choice for a substitute.   What you don't know, cause I didn't say, is that the supply is 50v, 1.5A.   > you choose to use a different package, you'll need to do some creative > mounting and heat sinking. The analog series current limiting > transistor will dissipate considerable heat at high loads.   There is no calibration in the circuit - the current limit is picked by rotating a pot until the current is limited where you want it. Hopefully this will be able to account for the different device. There was a poster who did this, so I'm probably OK.   I will mount it, isolated, to the steel frame. And at 1.5A that "should" be enough sinking.   > Sounds like too much work. I'll see if can find one in my junk pile. > I've been hoarding germanium devices for years for use in repairs.   My order is in, but thanks anyhow.   Bob

amdx <nojunk@knology.net>: Jan 05 10:38AM -0600 On 1/5/2017 10:02 AM, Bob Engelhardt wrote: > be replaced with a silicon one.     >My question is: why does the diode need > to be replaced?   Because the current limiting is partially determined by the relationship between the voltage drops of the diode (0.3V) and the emitter / base junction of the transistor. If you change only the transistor to (0.6V) you will probably never develop enough voltage on the transistor to start it conducting.   Mikek       --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

Bob Engelhardt <BobEngelhardt@comcast.net>: Jan 05 04:05PM -0500 On 1/5/2017 2:44 PM, Benderthe.evilrobot wrote: >...- the fact that the diode also > provides dome degree of temp-comp, is probably incidental.   Yeah - the diode and transistor are very thermally independent.

Bob Engelhardt <BobEngelhardt@comcast.net>: Jan 05 11:58AM -0500 On 1/5/2017 11:38 AM, amdx wrote: ... > If you change only the transistor to (0.6V) you will probably never > develop enough voltage on the transistor to start it conducting.   > Mikek   Ah! That makes perfect sense. Thank you.

Bob Engelhardt <BobEngelhardt@comcast.net>: Jan 05 12:46PM -0500 On 1/5/2017 12:07 PM, Bob Engelhardt wrote: > The transistor is a DLG600. ...   Oops - D _T_ G, as you said

Bob Engelhardt <BobEngelhardt@comcast.net>: Jan 05 12:07PM -0500 > If the transistor you need is a DTG600, NTE179 is a substitute and is germanium. I have one in stock if you want it. This is a TO-3 style transistor right?   > The posted schematic was a bit fuzy, so if I have the part number wrong, please post the correct one.     The transistor is a DLG600. I remember seeing that the NTE179 was a substitute, but the NTE179's that I found were just about as expensive. Especially compared to the $0.48 for the TIP32C.   Thanks just the same.   Bob

"Percival P. Cassidy" <Nobody@NotMyISP.net>: Jan 03 03:08PM -0500 On 01/03/2017 02:21 PM, MJC wrote:     > I thought that decades ago Microsoft had a convention of slashing an oh > to distinguish from zero (while others did the inverse). Maybe they had > to fall in line, for once!   Is it Norwegian that has a slashed oh? Having a slashed zero (although that is what I often write) could be confusing.   Perce

John Robertson <spam@flippers.com>: Jan 03 02:56PM -0800 > And we worry about bars on 7s.   > Peter Wieck > Melrose Park, PA   Interesting, we should ban the "U"s after Qs then as being redundant - save trillions, ban letters! (ducking)   Silent letters! Knife = Nif. Knight = Nit (silent 'e's, eh?)   While we are at it what is with 'to, too, and two'? Should be just one - 'to'.   Many more trillions saved...   John ;-#)#

John Robertson <spam@flippers.com>: Jan 03 06:14PM -0800 On 2017/01/03 4:56 PM, Dave Platt wrote:   > And, there was an even earlier proposal along somewhat similar lines:   > http://grammar.ccc.commnet.edu/grammar/twain.htm   And the link at the bottom of the page to the real Mark Twain article was broken years ago...however archive.org did have an earlier one which (I hope you-all don't mind) went as follows:   ----------(quote)----------- A SIMPLIFIED ALPHABET (by Mark Twain - Samuel Clements) (This article, written during the autumn of 1899, was about the last writing done by Mark Twain on any impersonal subject.)   I have had a kindly feeling, a friendly feeling, a cousinly feeling toward Simplified Spelling, from the beginning of the movement three years ago, but nothing more inflamed than that. It seemed to me to merely propose to substitute one inadequacy for another; a sort of patching and plugging poor old dental relics with cement and gold and porcelain paste; what was really needed was a new set of teeth. That is to say, a new ALPHABET.   The heart of our trouble is with our foolish alphabet. It doesn't know how to spell, and can't be taught. In this it is like all other alphabets except one--the phonographic. This is the only competent alphabet in the world. It can spell and correctly pronounce any word in our language.   That admirable alphabet, that brilliant alphabet, that inspired alphabet, can be learned in an hour or two. In a week the student can learn to write it with some little facility, and to read it with considerable ease. I know, for I saw it tried in a public school in Nevada forty-five years ago, and was so impressed by the incident that it has remained in my memory ever since.   I wish we could adopt it in place of our present written (and printed) character. I mean SIMPLY the alphabet; simply the consonants and the vowels--I don't mean any REDUCTIONS or abbreviations of them, such as the shorthand writer uses in order to get compression and speed. No, I would SPELL EVERY WORD OUT.   I will insert the alphabet here as I find it in Burnz's PHONIC SHORTHAND. [Figure 1] It is arranged on the basis of Isaac Pitman's PHONOGRAPHY. Isaac Pitman was the originator and father of scientific phonography. It is used throughout the globe. It was a memorable invention. He made it public seventy- three years ago. The firm of Isaac Pitman & Sons, New York, still exists, and they continue the master's work.   What should we gain?   First of all, we could spell DEFINITELY--and correctly--any word you please, just by the SOUND of it. We can't do that with our present alphabet. For instance, take a simple, every-day word PHTHISIS. If we tried to spell it by the sound of it, we should make it TYSIS, and be laughed at by every educated person.   Secondly, we should gain in REDUCTION OF LABOR in writing.   Simplified Spelling makes valuable reductions in the case of several hundred words, but the new spelling must be LEARNED. You can't spell them by the sound; you must get them out of the book.   But even if we knew the simplified form for every word in the language, the phonographic alphabet would still beat the Simplified Speller "hands down" in the important matter of economy of labor. I will illustrate:   PRESENT FORM: through, laugh, highland.   SIMPLIFIED FORM: thru, laff, hyland.   PHONOGRAPHIC FORM: [Figure 2]   To write the word "through," the pen has to make twenty-one strokes.   To write the word "thru," then pen has to make twelve strokes-- a good saving.   To write that same word with the phonographic alphabet, the pen has to make only THREE strokes.   To write the word "laugh," the pen has to make FOURTEEN strokes.   To write "laff," the pen has to make the SAME NUMBER of strokes--no labor is saved to the penman.   To write the same word with the phonographic alphabet, the pen has to make only THREE strokes.   To write the word "highland," the pen has to make twenty-two strokes.   To write "hyland," the pen has to make eighteen strokes.   To write that word with the phonographic alphabet, the pen has to make only FIVE strokes. [Figure 3]   To write the words "phonographic alphabet," the pen has to make fifty-three strokes.   To write "fonografic alfabet," the pen has to make fifty strokes. To the penman, the saving in labor is insignificant.   To write that word (with vowels) with the phonographic alphabet, the pen has to make only SEVENTEEN strokes.   Without the vowels, only THIRTEEN strokes. [Figure 4] The vowels are hardly necessary, this time.   We make five pen-strokes in writing an m. Thus: [Figure 5] a stroke down; a stroke up; a second stroke down; a second stroke up; a final stroke down. Total, five. The phonographic alphabet accomplishes the m with a single stroke--a curve, like a parenthesis that has come home drunk and has fallen face down right at the front door where everybody that goes along will see him and say, Alas!   When our written m is not the end of a word, but is otherwise located, it has to be connected with the next letter, and that requires another pen-stroke, making six in all, before you get rid of that m. But never mind about the connecting strokes--let them go. Without counting them, the twenty-six letters of our alphabet consumed about eighty pen-strokes for their construction--about three pen-strokes per letter.   It is THREE TIMES THE NUMBER required by the phonographic alphabet. It requires but ONE stroke for each letter.   My writing-gait is--well, I don't know what it is, but I will time myself and see. Result: it is twenty-four words per minute. I don't mean composing; I mean COPYING. There isn't any definite composing-gait.   Very well, my copying-gait is 1,440 words per hour--say 1,500. If I could use the phonographic character with facility I could do the 1,500 in twenty minutes. I could do nine hours' copying in three hours; I could do three years' copying in one year. Also, if I had a typewriting machine with the phonographic alphabet on it--oh, the miracles I could do!   I am not pretending to write that character well. I have never had a lesson, and I am copying the letters from the book. But I can accomplish my desire, at any rate, which is, to make the reader get a good and clear idea of the advantage it would be to us if we could discard our present alphabet and put this better one in its place--using it in books, newspapers, with the typewriter, and with the pen.   [Figure 6] --MAN DOG HORSE. I think it is graceful and would look comely in print. And consider--once more, I beg--what a labor-saver it is! Ten pen-strokes with the one system to convey those three words above, and thirty-three by the other! [Figure 6] I mean, in SOME ways, not in all. I suppose I might go so far as to say in most ways, and be within the facts, but never mind; let it go at SOME. One of the ways in which it exercises this birthright is--as I think--continuing to use our laughable alphabet these seventy-three years while there was a rational one at hand, to be had for the taking.   It has taken five hundred years to simplify some of Chaucer's rotten spelling--if I may be allowed to use to frank a term as that--and it will take five hundred years more to get our exasperating new Simplified Corruptions accepted and running smoothly. And we sha'n't be any better off then than we are now; for in that day we shall still have the privilege the Simplifiers are exercising now: ANYBODY can change the spelling that wants to.   BUT YOU CAN'T CHANGE THE PHONOGRAPHIC SPELLING; THERE ISN'T ANY WAY. It will always follow the SOUND. If you want to change the spelling, you have to change the sound first.   Mind, I myself am a Simplified Speller; I belong to that unhappy guild that is patiently and hopefully trying to reform our drunken old alphabet by reducing his whiskey. Well, it will improve him. When they get through and have reformed him all they can by their system he will be only HALF drunk. Above that condition their system can never lift him. There is no competent, and lasting, and real reform for him but to take away his whiskey entirely, and fill up his jug with Pitman's wholesome and undiseased alphabet.   One great drawback to Simplified Spelling is, that in print a simplified word looks so like the very nation! and when you bunch a whole squadron of the Simplified together the spectacle is very nearly unendurable.   The da ma ov koars kum when the publik ma be expektd to get rekonsyled to the bezair asspekt of the Simplified Kombynashuns, but--if I may be allowed the expression--is it worth the wasted time? [Figure 7]   To see our letters put together in ways to which we are not accustomed offends the eye, and also takes the EXPRESSION out of the words.   La on, Makduf, and damd be he hoo furst krys hold, enuf!   It doesn't thrill you as it used to do. The simplifications have sucked the thrill all out of it.   But a written character with which we are NOT ACQUAINTED does not offend us--Greek, Hebrew, Russian, Arabic, and the others--they have an interesting look, and we see beauty in them, too. And this is true of hieroglyphics, as well. There is something pleasant and engaging about the mathematical signs when we do not understand them. The mystery hidden in these things has a fascination for us: we can't come across a printed page of shorthand without being impressed by it and wishing we could read it.   Very well, what I am offering for acceptance and adopting is not shorthand, but longhand, written with the SHORTHAND ALPHABET UNREACHED. You can write three times as many words in a minute with it as you can write with our alphabet. And so, in a way, it IS properly a shorthand. It has a pleasant look, too; a beguiling look, an inviting look. I will write something in it, in my rude and untaught way: [Figure 8]   Even when _I_ do it it comes out prettier than it does in Simplified Spelling. Yes, and in the Simplified it costs one hundred and twenty-three pen-strokes to write it, whereas in the phonographic it costs only twenty-nine.   [Figure 9] is probably [Figure 10].   Let us hope so, anyway. -------(end quote)-------   John

MJC <gravity@mjcoon.plus.com>: Jan 03 07:21PM In article <o4depd$t90$1@dont-email.me>, diverse@tcp.co.uk says...   > Like a barred z comes from maths background, the slashed zero is > pretty universal   I thought that decades ago Microsoft had a convention of slashing an oh to distinguish from zero (while others did the inverse). Maybe they had to fall in line, for once!   Mike.

N_Cook <diverse@tcp.co.uk>: Jan 05 11:53AM > It's an old thread I know but this seems to be the most useful source of info on fixing these Yamaha units. Having not worked in electonics for a LONG time I'm basing my efforts on what's out there on t'interweb.   > Seems likely that my unit has the ST P14NF12FP's are blown based on the symptoms and common faults reported so I'm going to try to replace those. Seem easy enough to get hold of the ST P14NF12FP's relatively cheaply from Honkers if you are prepared to wait. I've ordered four of them and will solder them in somehow. Might re-site them on the heatsink though to avoid having to strip a load of components off the PCB mostly buried in mounds of rock hard white suff, presumably epoxy.   "non Yamaha" speaker lead ? Also blown fuse-resitors, slabby SMD <>0.2 ohm, plus other Qs blown perhaps

N_Cook <diverse@tcp.co.uk>: Jan 04 04:12PM On 04/01/2017 14:31, Jean-Pierre Coulon wrote:   > It has a lid with 4 screws, the leftmost beeing blocked by the chassis.   > Is the the right procedure?   > Regards,   So how much clearance , ratchet hex-bit wrench? cut-down hex-bit and flat spanner ?

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