"Andre Jute" said:


Andre Jute wrote:
Chris Hornbeck wrote:

On Tue, 16 Jan 2007 07:39:03 +0000, Eeyore
wrote:


In any event, an audible difference between DC and AC heating of DHTs indicates
to me that with AC there must be some signal modulation at 2 x line frequency,
like a tiny tremolo effect perhaps.


On the contrary, thermal time constant is too large for
heating to modulate emissivity even locally, and AC
heating is always used with hum nulling, which coincidentally
*exactly* (think carefully before disagreeing publicly)
also nulls all localized signal modulations.


The relevant circuits are at:
http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg
http://members.lycos.co.uk/fiultra/T44bis-'Populaire'-crct.jpg

The hum nulling, for visiting siliconheads who clearly don't know
anything about tube circuits, consists of the circuit in the Western
Electric 300B cathode (that's the lower part of the tube, chaps) made
up of two 100 ohm resistors and the 100 ohm pot. (This has, amazingly,
already been described by Don Pearce in this thread as if it is merely
a feedback mechanism. Nor did Pearce enquire after its purpose...
Perhaps Pearce has negative feedback on the brain, because he also
twice described the grid leak resistor as a negative feedback network;
interestingly, none of the other siliconitis sufferers afflicting us
know enough about tube circuits to correct this gross error by
Pearce.)

The designs are discussed in these texts:
http://members.lycos.co.uk/fiultra/T...mp%20INDEX.htm


If you and Arny really want to play in our sandbox,
at least do your homework first.

They don't want to play in our sandbox. They want to **** in it, to
suck the jam from our doughnut, to drain the glee from our hobby. It
offends these grim witchfinders that we are having fun.


A copy to UKRA so Pearce can't say I knock him behind his back. -- AJ


Gotta give credit where credit is due, Andre, even if it is only 1 dB.
The 100 ohm potmeter, shunted by both 100 ohms resistors, provide a
very tiny amount of local cathode feedback.

--

- Maggies are an addiction for life. -

On Fri, 19 Jan 2007 18:54:07 +0100, Sander deWaal
wrote:

"Andre Jute" said:


Andre Jute wrote:
Chris Hornbeck wrote:

On Tue, 16 Jan 2007 07:39:03 +0000, Eeyore
wrote:


In any event, an audible difference between DC and AC heating of DHTs indicates
to me that with AC there must be some signal modulation at 2 x line frequency,
like a tiny tremolo effect perhaps.


On the contrary, thermal time constant is too large for
heating to modulate emissivity even locally, and AC
heating is always used with hum nulling, which coincidentally
*exactly* (think carefully before disagreeing publicly)
also nulls all localized signal modulations.


The relevant circuits are at:
http://members.lycos.co.uk/fiultra/T...trafi-crct.jpg
http://members.lycos.co.uk/fiultra/T44bis-'Populaire'-crct.jpg

The hum nulling, for visiting siliconheads who clearly don't know
anything about tube circuits, consists of the circuit in the Western
Electric 300B cathode (that's the lower part of the tube, chaps) made
up of two 100 ohm resistors and the 100 ohm pot. (This has, amazingly,
already been described by Don Pearce in this thread as if it is merely
a feedback mechanism. Nor did Pearce enquire after its purpose...
Perhaps Pearce has negative feedback on the brain, because he also
twice described the grid leak resistor as a negative feedback network;
interestingly, none of the other siliconitis sufferers afflicting us
know enough about tube circuits to correct this gross error by
Pearce.)

The designs are discussed in these texts:
http://members.lycos.co.uk/fiultra/T...mp%20INDEX.htm


If you and Arny really want to play in our sandbox,
at least do your homework first.

They don't want to play in our sandbox. They want to **** in it, to
suck the jam from our doughnut, to drain the glee from our hobby. It
offends these grim witchfinders that we are having fun.


A copy to UKRA so Pearce can't say I knock him behind his back. -- AJ


Gotta give credit where credit is due, Andre, even if it is only 1 dB.
The 100 ohm potmeter, shunted by both 100 ohms resistors, provide a
very tiny amount of local cathode feedback.

Don't worry Sander, Jute is back in my killfile with Allison. He only
got out temporarily because I changed to a new laptop.

d

--
Pearce Consulting
http://www.pearce.uk.com

Sander deWaal wrote:
"Andre Jute" said:


Andre Jute wrote:
Chris Hornbeck wrote:

On Tue, 16 Jan 2007 07:39:03 +0000, Eeyore
wrote:


In any event, an audible difference between DC and AC heating of DHTs indicates
to me that with AC there must be some signal modulation at 2 x line frequency,
like a tiny tremolo effect perhaps.


On the contrary, thermal time constant is too large for
heating to modulate emissivity even locally, and AC
heating is always used with hum nulling, which coincidentally
*exactly* (think carefully before disagreeing publicly)
also nulls all localized signal modulations.


The relevant circuits are at:
http://members.lycos.co.uk.cob-web.o...trafi-crct.jpg
http://members.lycos.co.uk.cob-web.org:8888/fiultra/T44bis-'Populaire'-crct.jpg

The hum nulling, for visiting siliconheads who clearly don't know
anything about tube circuits, consists of the circuit in the Western
Electric 300B cathode (that's the lower part of the tube, chaps) made
up of two 100 ohm resistors and the 100 ohm pot. (This has, amazingly,
already been described by Don Pearce in this thread as if it is merely
a feedback mechanism. Nor did Pearce enquire after its purpose...
Perhaps Pearce has negative feedback on the brain, because he also
twice described the grid leak resistor as a negative feedback network;
interestingly, none of the other siliconitis sufferers afflicting us
know enough about tube circuits to correct this gross error by
Pearce.)

The designs are discussed in these texts:
http://members.lycos.co.uk.cob-web.o...mp%20INDEX.htm


If you and Arny really want to play in our sandbox,
at least do your homework first.

They don't want to play in our sandbox. They want to **** in it, to
suck the jam from our doughnut, to drain the glee from our hobby. It
offends these grim witchfinders that we are having fun.


A copy to UKRA so Pearce can't say I knock him behind his back. -- AJ


Gotta give credit where credit is due, Andre, even if it is only 1 dB.
The 100 ohm potmeter, shunted by both 100 ohms resistors, provide a
very tiny amount of local cathode feedback.

I didn't say it wasn't *also* a feedback circuit to some
fractional extent. What I said was that the public
idiot Don "Bluster" Pearce mistook the AC humbuster circuit for
solely a feedback circuit, and missed its primary purpose. What I said
was that the public idiot Don "Bluster" Pearce mistook the grid leak
circuit for a feedback circuit. What I said was the public idiot
Don "Bluster" Pearce clearly knows buggerall about tube circuits
and should therefore keep his nose out of what he is totally
ignorant about. Bluster Pearce has run away now to shelter
behind his killfile, so the rest of us can get on with the business
of tubes.

- Maggies are an addiction for life. -

Coca-cola is cheaper.

Always wanted to say that...

Andre Jute
The definition of darwinian accident waiting to happen: Don "Bluster"
Pearce.

Andre Jute wrote:

Sander deWaal wrote:

Gotta give credit where credit is due, Andre, even if it is only 1 dB.
The 100 ohm potmeter, shunted by both 100 ohms resistors, provide a
very tiny amount of local cathode feedback.

I didn't say it wasn't *also* a feedback circuit to some
fractional extent. What I said was that the public
idiot Don "Bluster" Pearce mistook the AC humbuster circuit for
solely a feedback circuit

That sounds remarkably unlikely !

Graham

Andrew Jute McCoy exuded more lies:

I didn't say it wasn't *also* a feedback circuit to some
fractional extent.

Either it is ZNF or it is not. Now that you have admitted that it is
not, then you have also admitted to all the rest of your lies... Not
the least of which is that you actually have an amp, rather than a
concatenation of loose parts and a bad schematic of a marginal plan of
a dysfunctional amp.

Show the amp. If Raymond can do it without fanfare, blather, pretense
or reams of crap, perhaps you can do it even _with_ all of that.

Peter Wieck
Wyncote, PA

Peter Wieck wrote:

Andrew Jute McCoy exuded more lies:


I didn't say it wasn't *also* a feedback circuit to some
fractional extent.


Either it is ZNF or it is not. Now that you have admitted that it is
not, then you have also admitted to all the rest of your lies... Not
the least of which is that you actually have an amp, rather than a
concatenation of loose parts and a bad schematic of a marginal plan of
a dysfunctional amp.

Show the amp. If Raymond can do it without fanfare, blather, pretense
or reams of crap, perhaps you can do it even _with_ all of that.

We have seen photos of what Andre claims to be the amp, though he lied
about the date. Obviously next time he will change the date on his camera
before taking any 'old' photographs.
The photograph was tastefully posed, hiding the bottom of the 300Bs
so we couldn't see if the valves were plugged in or just resting there;
the chassis is supposed to have different valve sockets depending on
what he is playing with at the time.

Just noticed another nice feature of the 'finalized' circuit:
fixed 2.4v bias, max input voltage 2vRMS!

--
Eiron.

Eiron wrote:

We have seen photos of what Andre claims to be the amp, though he lied
about the date. Obviously next time he will change the date on his camera
before taking any 'old' photographs.

A couple of things: The tubes in the submitted photo were Chinese
Silvertones. What was artfully posed behind were the _boxes_ that
purportedly containted the WE variety. Then, later, came a B&W photo of
a WE tube in a glass case with one of its vanity-published books behind
(also showing a 30 year-old photograph). But no actual connection
between any actual WE tube and any actual "real McCoy" amp. Even the
317s were concealed.

The amp in the picture was at best a breadboard attempt, not even the
beginnings of a finished product that one would leave exposed to polite
society.

So, we have a "finalized" amp that has had its "circuit updated". One
shudders to think how many more iterations this accretion of loose
parts will experience before either its creator shucks its mortal coil
or his landlord gets tired of changing fuses, or its tiny little
bed-sit burns down. But one thing is almost a certainty. It will never
be complete to any reliable operational degree.

Consider the elephant: Much trumpeting and activity, not much product
to show for a couple of years thereafter. In McCoy's case, the
tumpeting happens every day but lacks the activity and will produce no
product... Oh, right... other than the excrement it dumps here.

Peter Wieck
Wyncote, PA