Nobody wrote:> On Tue, 12 May 2009 19:12:23 +0100, Eeyore wrote: > > >> I liked C as a less verbose version of Pascal. > >> > >> Procedure Execute; > >> Var i:array[1..10] of integer; > >> Begin > >> End; > >> > >> becomes > >> > >> void Execute() > >> { > >> int i[10]; > >> } > >> > >> What's not to like? :D > > The type syntax can be a bit confusing if you are mixing prefix and > postfix operators, particularly in conjunction with function pointers (but > most people would just use a typedef), or if you want to specify the type > without naming a variable (e.g. for a cast).I don't need that shit for simple embedded programming.> > VOID ! > > Huh? What's wrong with "void"? Would you have preferred "()" (a > zero-element tuple) like in functional languages?I'd prefer PL/M's "return value".> > It drives me nuts. Also things like = and == > > Are you advocating for ":="? Using "=" for both assignment and comparison > isn't an option in languages where boolean expressions aren't relegated to > the tests of if/while instructions.You'd be amazed how unneccesary it is. Graham
Building a class A audio amplifier - no audio out
Started by ●May 11, 2009
Reply by ●May 12, 20092009-05-12
Reply by ●May 13, 20092009-05-13
On May 12, 8:27=A0am, mrdarr...@gmail.com wrote:> On May 12, 12:34=A0am, stratu...@yahoo.com wrote: > > > > > > > On May 11, 8:00=A0pm, Jon Kirwan <j...@infinitefactors.org> wrote: > > > > On Mon, 11 May 2009 13:31:51 -0700 (PDT), stratu...@yahoo.com wrote: > > > >Well then perhaps this 'golden oldie' might be of interest. > > > > >http://www.swtpc.com/mholley/PopularElectronics/Dec1967/PE_Dec1967.h=tm> > > > I remember it! =A0There was a follow-up article with another version,=as> > > I recall. > > > > Jon > > > You probably mean this > > >http://www.swtpc.com/mholley/PopularElectronics/Jul1969/PE_Jul1969.htm > > > which I built in high school. It had an annoying tendency to blow the > > outputs. And this > > >http://www.swtpc.com/mholley/PopularElectronics/Oct1970/PE_Oct1970.htm > > > and another family member > > >http://www.swtpc.com/mholley/PopularElectronics/Oct1971/PE_Oct_1971_P... > > > Enough of memory lane for now. > > > G=B2 > > All of those tended to fry your speakers? > > MichaelThe only units I built were the 2 Tiger amps running right at 60 volts power supply - I don't remember how far the supply drooped under load, it was 37 years ago. The finals would blow and take out the power supply fuse. The output cap (would never run a single supply amp again) kept any DC from the speakers. No speakers ever failed. I later worked in a stere repair shop and a customer brought in a Universal Tiger pair but I could never get it running properly for him as it had a nasty tendency to oscillate. I had some friends with Super Tiger amps and AFAIK they worked properly. My antique stuff now is a Hafler preamp, Technics parametric equalizer, Adcom power amp and an HK Citation 15 tuner G=B2
Reply by ●May 13, 20092009-05-13
Eeyore wrote:> > "Michael A. Terrell" wrote: > > > Eeyore wrote: > > > > > > Half the trouble is the most half-assed DIY websites use exclusively obsolete > > > parts. Thinks 2N2222 for example. Metal can, expensive and outperformed now by a > > > 2c TO-92 device. > > > > Idiot! The PN2222 is the same die in a TO-92 package, and the > > MMBT2222 is the same die in a SOT-23 package it isn't obsolete, just > > repackaged for modern designs. > > I know. Its parameters are still inferior to later similar devices though.Bullshit. It is what it is: a jelly bean, general purpose transistor. The reason you don't like it, is that it is a JEDEC registered part, instead of your lame European numbering system. It was never designated as a low noise audiofool part.> > 2N2222 is considered the generic name for the family, since it was first. > > Do you have a problem with using the correct prefix ?Apparently, you do. Since it is available in multiple packages and mounting styles, the original number is the appropriate one. The people posting simple designs online have no idea which package will be used, and by whom.. If they want metal, they use the original. If they can use TO-92, they use the PN, and if they want surface mount, they use the MMBT. The online designs aren't expected to be exotic performers. They are simple circuits, to be built with easy to find parts. If you plane top build 10,000 of something, you can comb the world for whatever you want, but if you are building a single item and have no local source of parts, then the recommended parts are fine. You can't get it through your thick skull that beginners need things to be simple enough to learn from. No matter how highly you think of yourself, you were not born knowing how to do anything other than breathe, and fill your diapers. -- You can't have a sense of humor, if you have no sense!
Reply by ●May 13, 20092009-05-13
mrdarrett@gmail.com wrote:> > On May 11, 1:31 pm, stratu...@yahoo.com wrote: > > On May 11, 8:30 am, mrdarr...@gmail.com wrote:> On May 11, 8:16 am, stratu...@yahoo.com wrote: > > > > <snip> > > > > Lots of good stuff here > > > > > > >http://sound.westhost.com/ > > > > > > > G� > > > > > > Ah, thank you for the reply. > > > > > > One thing I noticed is, the larger amps on westhost.com (10W+) need > > > split power supplies (+/-). I'd like to start with something > > needing > > > just 0V-6V or 0V-12V. > > > > > > Thanks again, > > > > > > Michael > > > > Well then perhaps this 'golden oldie' might be of interest. > > > > http://www.swtpc.com/mholley/PopularElectronics/Dec1967/PE_Dec1967.htm > > > > G� > > Thanks a bunch! > > Michael"The Brute 70" I built this one in high school. I made my first PC boards for it. They took the circuit from the RCA Data book and drew up plans around them. I saw a lot of early commercial solid state PA amps built from the same basic circuit. Some had been ion daily use for 20 years before they needed repairs. The big change was the addition of a output transformer to match them to either a 25 or 70 volt line speaker system. http://www.swtpc.com/mholley/PopularElectronics/Feb1967/PE_Feb1967.htm -- You can't have a sense of humor, if you have no sense!
Reply by ●May 13, 20092009-05-13
On 2009-05-12, mrdarrett@gmail.com <mrdarrett@gmail.com> wrote:> On May 11, 8:03 pm, Nobody <nob...@nowhere.com> wrote: >> > On May 11, 1:44 pm, Eeyore <rabbitsfriendsandrelati...@hotmail.com> >> > wrote: >> >> I was offered a job programming in C back around 1984. I took one look >> >> at the bizarre syntax and ran away. >> >> That "bizarre" syntax is pretty much the industry standard nowadays. C++, >> C#, Java, and JavaScript all look very similar. Any deviation from C >> syntax (e.g. Python) is considered bizarre. >> >> On Mon, 11 May 2009 13:57:28 -0700, mrdarrett wrote: >> > How could you be offered a job in C programming if you didn't know C >> > programming? (thoroughly confused) That would never fly over here. >> >> In 1984, C was still a fairly uncommon language. It wouldn't be >> unreasonable to prefer someone with a reasonable amount of overall >> programming experience (particularly if it's experience in the relevant >> domain) who would need to learn C over someone with less overall >> experience (or less relevant experience) with some C. Learning a new >> language is easier than learning programming. >> >> Of course, that doesn't hold if hiring is done by HR types with no >> knowledge of the field (and no willingness to consult). A classic example >> was when Java took off, companies were advertising for programmers with 2 >> or 3 years' Java experience when Java's existence had been public >> knowledge for less than a year. > > > Yes, I remember when Java was new. Makes sense from that > perspective. But I'm surprised why a seasoned programmer would run > away screaming from C. > > I liked C as a less verbose version of Pascal. > > Procedure Execute; > Var i:array[1..10] of integer; > Begin > End; > > becomes > > void Execute() > { > int i[10]; > } >can't do this in C Procedure wrapper(x:integer) procedure recursive(y:integer) begin if something(y,x) then recursive(y+1) end; begin recursive(0) end;
Reply by ●May 13, 20092009-05-13
On May 13, 4:16=A0am, Jasen Betts <ja...@xnet.co.nz> wrote:> On 2009-05-12, mrdarr...@gmail.com <mrdarr...@gmail.com> wrote: > > > > > On May 11, 8:03=A0pm, Nobody <nob...@nowhere.com> wrote: > >> > On May 11, 1:44=A0pm, Eeyore <rabbitsfriendsandrelati...@hotmail.com= > > >> > wrote: > >> >> I was offered a job programming in C back around 1984. I took one l=ook> >> >> at the bizarre syntax and ran away. > > >> That "bizarre" syntax is pretty much the industry standard nowadays. C=++,> >> C#, Java, and JavaScript all look very similar. Any deviation from C > >> syntax (e.g. Python) is considered bizarre. > > >> On Mon, 11 May 2009 13:57:28 -0700, mrdarrett wrote: > >> > How could you be offered a job in C programming if you didn't know C > >> > programming? =A0(thoroughly confused) =A0That would never fly over h=ere.> > >> In 1984, C was still a fairly uncommon language. It wouldn't be > >> unreasonable to prefer someone with a reasonable amount of overall > >> programming experience (particularly if it's experience in the relevan=t> >> domain) who would need to learn C over someone with less overall > >> experience (or less relevant experience) with some C. Learning a new > >> language is easier than learning programming. > > >> Of course, that doesn't hold if hiring is done by HR types with no > >> knowledge of the field (and no willingness to consult). A classic exam=ple> >> was when Java took off, companies were advertising for programmers wit=h 2> >> or 3 years' Java experience when Java's existence had been public > >> knowledge for less than a year. > > > Yes, I remember when Java was new. =A0Makes sense from that > > perspective. =A0But I'm surprised why a seasoned programmer would run > > away screaming from C. > > > I liked C as a less verbose version of Pascal. > > > Procedure Execute; > > Var i:array[1..10] of integer; > > Begin > > End; > > > becomes > > > void Execute() > > { > > =A0 int i[10]; > > } > > can't do this in C > > =A0Procedure wrapper(x:integer) > =A0procedure recursive(y:integer) > =A0begin > =A0 =A0if something(y,x) then recursive(y+1) > =A0end; > =A0begin > =A0 =A0recursive(0) > =A0end;Probably not as written, but couldn't you move recursive() to outside of wrapper() ? If it needs variables local to wrapper(), pass the addresses of the variables to recursive()...? Michael
Reply by ●May 13, 20092009-05-13
On May 12, 9:43=A0pm, "Michael A. Terrell" <mike.terr...@earthlink.net> wrote:> mrdarr...@gmail.com wrote: > > > On May 11, 1:31 pm, stratu...@yahoo.com wrote: > > > On May 11, 8:30 am, mrdarr...@gmail.com wrote:> On May 11, 8:16 am, s=tratu...@yahoo.com wrote:> > > > <snip> > > > =A0> > Lots of good stuff here > > > > =A0> >http://sound.westhost.com/ > > > > =A0> > G=B2 > > > > =A0> Ah, thank you for the reply. > > > > =A0> One thing I noticed is, the larger amps on westhost.com (10W+) n=eed> > > =A0> split power supplies (+/-). =A0I'd like to start with something > > > needing > > > =A0> just 0V-6V or 0V-12V. > > > > =A0> Thanks again, > > > > =A0> Michael > > > > Well then perhaps this 'golden oldie' might be of interest. > > > >http://www.swtpc.com/mholley/PopularElectronics/Dec1967/PE_Dec1967.htm > > > > G=B2 > > > Thanks a bunch! > > > Michael > > =A0 =A0"The Brute 70" I built this one in high school. =A0I made my first=PC> boards for it. =A0They took the circuit from the RCA Data book and drew u=p> plans around them. =A0I saw a lot of early commercial solid state PA amps > built from the same basic circuit. =A0Some had been ion daily use for 20 > years before they needed repairs. =A0The big change was the addition of a > output transformer to match them to either a 25 or 70 volt line speaker > system. > > http://www.swtpc.com/mholley/PopularElectronics/Feb1967/PE_Feb1967.htm > -- > You can't have a sense of humor, if you have no sense!Interesting. Are Q6 and Q7 both supposed to be NPN? And what is this RCA Data Book? Thanks, Michael
Reply by ●May 13, 20092009-05-13
mrdarrett@gmail.com wrote:> On May 12, 9:43 pm, "Michael A. Terrell" <mike.terr...@earthlink.net> > wrote: >> mrdarr...@gmail.com wrote: >> >>> On May 11, 1:31 pm, stratu...@yahoo.com wrote: >>>> On May 11, 8:30 am, mrdarr...@gmail.com wrote:> On May 11, 8:16 >>>> am, stratu...@yahoo.com wrote: >> >>>> <snip> >>>>>> Lots of good stuff here >> >>>>>> http://sound.westhost.com/ >> >>>>>> G� >> >>>>> Ah, thank you for the reply. >> >>>>> One thing I noticed is, the larger amps on westhost.com (10W+) >>>>> need split power supplies (+/-). I'd like to start with something >>>> needing >>>>> just 0V-6V or 0V-12V. >> >>>>> Thanks again, >> >>>>> Michael >> >>>> Well then perhaps this 'golden oldie' might be of interest. >> >>>> http://www.swtpc.com/mholley/PopularElectronics/Dec1967/PE_Dec1967.htm >> >>>> G� >> >>> Thanks a bunch! >> >>> Michael >> >> "The Brute 70" I built this one in high school. I made my first PC >> boards for it. They took the circuit from the RCA Data book and drew >> up plans around them. I saw a lot of early commercial solid state PA >> amps built from the same basic circuit. Some had been ion daily use >> for 20 years before they needed repairs. The big change was the >> addition of a output transformer to match them to either a 25 or 70 >> volt line speaker system. >> >> http://www.swtpc.com/mholley/PopularElectronics/Feb1967/PE_Feb1967.htm >> -- >> You can't have a sense of humor, if you have no sense! > > > Interesting. Are Q6 and Q7 both supposed to be NPN? >Yes. Those were times when high-power silicon PNP transistors were not easily available. The arrangement was sometimes called a quasi-complementary circuit because it's not a true symmetrical NPN-PNP complementary circuit. I don't know if RCA invented the circuit, but it was they who made it popular. The circuit was presented in the 1968 edition of RCA Transistor Manual, one of the first reference books I owned.> And what is this RCA Data Book? >Mike is probably talking about the same book.
Reply by ●May 13, 20092009-05-13
mrdarrett@gmail.com wrote:> "Michael A. Terrell" <mike.terr...@earthlink.net> wrote: > > > > http://www.swtpc.com/mholley/PopularElectronics/Feb1967/PE_Feb1967.htm > > Interesting. Are Q6 and Q7 both supposed to be NPN?Yes, it's commonly called a 'quasi complementary pair' output. One side is a Darlington, the other is a Sz... pair ( never can remember how to spell it ) or 'compound transistor'. This was done long ago because it was difficult at the time to make high power Si PNP power devices. It's not a problem now and no-one uses it any more because of the inherent gm mismatch.> And what is this RCA Data Book?The same as the one I've got by the looks of it ! '69 I think. Graham
Reply by ●May 13, 20092009-05-13
pimpom wrote:> mrdarrett@gmail.com wrote: > > > > Interesting. Are Q6 and Q7 both supposed to be NPN? > > > Yes. Those were times when high-power silicon PNP transistors were not > easily available. The arrangement was sometimes called a quasi-complementary > circuit because it's not a true symmetrical NPN-PNP complementary circuit. I > don't know if RCA invented the circuit, but it was they who made it popular. > The circuit was presented in the 1968 edition of RCA Transistor Manual, one > of the first reference books I owned. > > > And what is this RCA Data Book? > > Mike is probably talking about the same book.I have it too. It was a poor transitional phase to pure complmentary output stages. The method lasted some time though. Graham
