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In that case you've changed your point of view and have made yourself lookEeyore wrote:
John Fields wrote:
Then you agree that wiring
TRACKING !
has a nasty habit of upsetting perfectly
loaded applecarts and that your pointers will help to keep that from
happening?
---
Do you consciously persist in your buffoonery, or is it involuntary?
My statement, to Kevin, was:
"Wiring has a nasty habit of upsetting perfectly loaded applecarts.",
not: "PCB wiring has a nasty habit of upsetting perfectly loaded
applecarts."
Can you understand the difference between the two?
Probably not, so I'll explain it to you:
The former case is general enough that it includes improperly shielded
conductors, conductors running too close to each other, and all manner
of problems caused by wiring, including PCB wiring.
The latter applies specifically to PBC's and is too restrictive to apply
to every situation, thereby being the reason I chose the more general
term.
---John Fields wrote:
Eeyorewrote:
John Fields wrote:
Eeyore wrote:
John Fields wrote:
Eeyore wrote:
John Fields wrote:
"Kevin Aylward" wrote:
I mean, why should I build it? What possible purpose could that serve, that
would not be known already?
---
Wiring has a nasty habit of upsetting perfectly loaded applecarts.
Then the applecart wasn't designed right.
---
Whoosh...
The perfectly loaded applecart (properly designed circuit) can easily be
upset if the PCB layout (wiring) is improperly done.
That's *tracking* not 'wiring'.
---
Is that a Right-Pondian term?
Well do you call it 'tracing' as in traces ?
---
No, we call it wiring as in 'wiring'.
But it's not a wire.
---That is, when referring to the conglomeration of traces on the board in
general. When referring to single conductors or to a few, we generally
call them 'traces' or, less commonly, 'tracks'.
---
I've always heard of it referred to and have called it "wiring" as in:
"You got the wiring wrong on that PCB."
A WIRE is a single usually circular conductor or bundle of same covered by insulation.
I haven't seen many PCBs made of them. None in fact.
---Do you guys say: "You got the tracking wrong on that PCB"?
Yes.
---
How you manage to mangle the language is beyond me.
It's called ENGLISH not Americanlish.
---Sounds kind of ambiguous to me, like you're admonishing FEDEX or
somebody like that.
I take it, though, you take my point?
That you're being STUPID as usual.
The word these days is PCB *not* PWB.
---
Huh???
_Me_ stupid?
VERY and totally out of touch.
Nope. Beard fooled ya?Did you play in ZZ Top btw ?
"olivier.scalb...@algosyn.com" wrote:
Hello,
First, I must say that I have not done analog electronics since a long
time. So please be indulgent !
I want to do a small class-A music amplifier + preamp. I want to find
the best trade-off between simplicity and sound quality.
My approach is very incremental. I have started with one old 2N3055,
polarized with voltage divider composed of 2 resistors.
As the gain of the transistor is to low I finally put a (too?) small
BC546 in front of the 2N3055 (Darlington).
See schema:
http://scalbert.dyndns.org/electronics/amplifier/ampli1.png
As I need a preamp for the volume control, I have add another BC546 to
amplify the input signal.
See schema:
http://scalbert.dyndns.org/electronics/amplifier/preamp1.png
The DC is provided by a lab power supply (0-30V, 0-3A). I use from 5V
to 12V as the 2N3055 heatsink is to small.
When I first test it, I was expected to have a crappy and plastic
sound, and even smoke, but I was very surprised. The sound is clean
and contains a lot of details (speaker: B&W DM110).
What I want to do now is to improve:
- the schematic (there are certainly mistakes ...)
- the component choice (better capacitor ? , better transistor ?)
Any remarks and suggestions are welcomed !
Stop mucking about with stuff you don't understand and simply buy a modern
hi-fi amp. Power amps are a real speciality (especially if you want them
to be stable). It's no place for a beginner.
Do you understand stabilty criteria for example. What's a Bode plot ? etc
Graham (designer of stable pro-audio power amps since 1980)
Agree, but I have no negative supply yet. I have to found or buy orNever even heard of that one. No purpose designed audio op-amp swings rail
to rail btw. If he can provide a negative supply (that eliminates the silly
output coupling cap too) and ensure DC stability he might look at the
venerable but decent TL071/2 etc.
Graham
It's the gate-gate caps that mystify me, downstream of the gateJohn Larkin wrote:
On Mon, 20 Oct 2008 17:33:20 GMT, "Kevin Aylward"
kaExtractThis@kevinaylward.co.uk> wrote:
John Fields wrote:
On Sun, 19 Oct 2008 19:32:49 GMT, "Kevin Aylward"
kaExtractThis@kevinaylward.co.uk> wrote:
I mean, why should I build it? What possible purpose could that
serve, that would not be known already?
---
Wiring has a nasty habit of upsetting perfectly loaded applecarts.
And it what way do the properties of "wiring" transcend the laws of
physics such that such "wiring" is unable to be inclued in
simulations?
I'm guessing that the output fets will RF oscillate big time.
Especially with those nice gate-gate caps downstream of the gate
resistors.
Yes...and er... as now doubt well known in this NG, by now, the mosfet1000
was designed in 1982. Just where do you guess, was the placement of the
mosfet gate resistors, such that the amp actually worked? Unfortunately, no
pack of Guinness for the correct answer.
Did you include the wiring - pcb layout, wire bonds, capacitance toWiring certainly matters here.
Indeed, and what part of "And it what way do the properties of "wiring"
transcend the laws of physics such that such "wiring" is unable to be
inclued is simulations?" did you miss?