Chip with simple program for Toy

[John Fields]

On Fri, 18 Mar 2005 16:42:24 +0000, John Woodgate
<jmw@jmwa.demon.contraspam.yuk> wrote:

I read in sci.electronics.design that John Fields <jfields@austininstrum
ents.com> wrote (in <tevl31d7hifd06bbarahutdhrnc1k8afiq@4ax.com&gt about
'Newsgroup Nazi', on Fri, 18 Mar 2005:
On Thu, 17 Mar 2005 17:18:21 -0800, "Watson A.Name - \"Watt Sun, the
Dark Remover\"" <NOSPAM@dslextreme.com> wrote:


"John Fields" <jfields@austininstruments.com> wrote in message
news18k31l32kn6ueeeujh6s2s8bdkgj4vv7d@4ax.com...

---
Yeah, goos idea. That makes it _really_ convenient for whoever's
pushing you into the oven.

Is that 'goos idea' a Freudian slip??

---
Just a trypo, AFAIK...

What would it refer to if it was Freudian?

Well, you might well push a goose into the oven. Alternatively, someone
might goose YOU, so that you projected yourself into the oven.

---
Ah, yesss... That would make _me_ the butt of the joke!^)

--
John Fields

 

[John Fields]

On Fri, 18 Mar 2005 18:12:52 GMT, Rich Grise <richgrise@example.net>
wrote:

On Fri, 18 Mar 2005 10:14:49 -0600, John Fields wrote:

On Thu, 17 Mar 2005 17:18:21 -0800, "Watson A.Name - \"Watt Sun, the Dark
Remover\"" <NOSPAM@dslextreme.com> wrote:


"John Fields" <jfields@austininstruments.com> wrote in message
news18k31l32kn6ueeeujh6s2s8bdkgj4vv7d@4ax.com...

---
Yeah, goos idea. That makes it _really_ convenient for whoever's
pushing you into the oven.

Is that 'goos idea' a Freudian slip??

---
Just a trypo, AFAIK...

What would it refer to if it was Freudian?

I got "goose step"...

---
That would be closer to Hitler than to Freud, no?

--
John Fields

 

[Jim Thompson]

On Sat, 19 Mar 2005 08:44:11 +1100, Franc Zabkar
<fzabkar@optussnet.com.au> wrote:

On Fri, 18 Mar 2005 12:39:13 +0000 (GMT), Tony Williams
tonyw@ledelec.demon.co.uk> put finger to keyboard and composed:

In order for your ISP
to know that it was a test post they must have
examined the *content* of the post.

This is a dangerous thing for an ISP to do, because
all posts they propagate may reasonably be assumed
to have been seen by them and they are satisfied
that no posts have an illegal content. Therefore
they lay themselves open to prosecution if a post
is subsequently the cause of legal action.

My ISP makes a big fuss about never looking at the
content of a post. In this way they maintain their
status as a common carrier (like the post office).

I would like to see *all* ISPs filter content that contains spam,
racial vilification, malware, binary attachments (in non-binary NGs),
and other inappropriate content. If the law needs to be rewritten for
modern times, then so be it.

BTW, John, it appears that your newsgroup access is working. It's a
shame we aren't discussing something more pertinent. ;-)


- Franc Zabkar

We have true freedom of speech in this country, so any blocking or
censoring anything other than advertising is guaranteed to get you
sued.

Your "inappropriate content" may be my tasty morsel. We've had
several court rulings here which say you have no legal protection
against being offended.

About the only "content" laws that hold up against challenge are those
that limit what minors may be exposed to.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

 

[John Fields]

On Sat, 19 Mar 2005 08:43:59 +1100, Franc Zabkar
<fzabkar@optussnet.com.au> wrote:

On Thu, 17 Mar 2005 18:29:20 -0600, John Fields
jfields@austininstruments.com> put finger to keyboard and composed:
---
Just because your ISP doesn't carry sbcglobal.help.tech.newsgroups
doesn't mean it doesn't exist.

That's not the point. If you had crossposted to 100 newsgroups, then
nearly everybody who responded to your message (who was an Agent user)
would have had their reply bounce.

---
I can't imagine why. I use Agent and I've often replied to messages
crossposted by other Agent users with no problems. Or even to other
Agent users _with_ problems.
---

If I were testing my Usenet access, I'd just send a regular message,
or reply to an existing thread. If the message doesn't appear in my
normal newsfeed, then I'd look for it at Google Groups. BTW, I don't
necessarily agree with all the netiquette guidelines, but I observe
them anyway. I reckon if I can annoy the least number of people my
life will be a lot easier.

---
Yeah, goos idea. That makes it _really_ convenient for whoever's
pushing you into the oven.

Standards exist for a good reason. For example, I like to drive on the
left side of the road, but when I visit the USA I defer to local
custom. Sometimes there really is no room for individual expression
...

---
Driving on the right side (as opposed to the wrong side) of the road
over here isn't just a good idea and a local custom, it's the law.
Posting a test message to non-test newsgroups isn't against any law,
and whether it's identified as a test or disguised as something else,
the fact remains it's a test message.
---

BTW, you are not alone with your NG problems. Many years ago I was
with an ISP called OneNet. NoneNet had not allocated enough disc
capacity to their Usenet service, which meant that more often than not
I was unable to post messages. When my posts did go through, they were
not being relayed to the wider Internet, which meant that only other
NoneNet users were seeing them. A visit to the Usenet archives at
DejaNews confirmed my suspicions.

---
Ok, but that's wildly different from singling out one post and
refusing to broadcast it because of one individual's objection to the
contents of the subject line.

--
John Fields

 

[John Fields]

On Sat, 19 Mar 2005 08:44:11 +1100, Franc Zabkar
<fzabkar@optussnet.com.au> wrote:

On Fri, 18 Mar 2005 12:39:13 +0000 (GMT), Tony Williams
tonyw@ledelec.demon.co.uk> put finger to keyboard and composed:

In order for your ISP
to know that it was a test post they must have
examined the *content* of the post.

This is a dangerous thing for an ISP to do, because
all posts they propagate may reasonably be assumed
to have been seen by them and they are satisfied
that no posts have an illegal content. Therefore
they lay themselves open to prosecution if a post
is subsequently the cause of legal action.

My ISP makes a big fuss about never looking at the
content of a post. In this way they maintain their
status as a common carrier (like the post office).

I would like to see *all* ISPs filter content that contains spam,
racial vilification, malware, binary attachments (in non-binary NGs),
and other inappropriate content. If the law needs to be rewritten for
modern times, then so be it.

---
IMO, if there's any legislation to be enacted, it should penalize the
perpetrators, not the ISP's. After all, they're just providing access
to the network and can't be made responsible for the idiocy of some of
its users. To legislate against them would be to find a company
providing public transportation an accessory to murder because someone
took the bus to a liquor store and then robbed and killed the owner of
the store.
---

BTW, John, it appears that your newsgroup access is working. It's a
shame we aren't discussing something more pertinent. ;-)

---
It's working because I blew off Prodigy and their provincial bullshit
and hooked up with Giganews.

--
John Fields

 

[Larry Brasfield]

"John Fields" <jfields@austininstruments.com> wrote in message
news:emr041dnld7pmj6v7emf5bdsvng962tqgv@4ax.com...

On Tue, 22 Mar 2005 12:32:16 -0600, Michael Noone
mnoone.uiuc.edu@127.0.0.1> wrote:
....
+400V>--+-----+---D S---+----------+-------->>--+
| | G | | |
| | | [ZENER] | |
[R1] [R2] | |K | |
| | +-----+ | |
| | | | |
| +-----+ | |
| | | |
+-------------------+ Vin [R2] |
| | | | | |
| D /-|--+ | [RL]
|K G---< | | |
[REF] S \+|-------+-----+ |
| | | | | |
| | | [R3] [C1] |
| | | | | |
GND>----+-----------+-------+--------+-----+-->>--+


Use a little high-voltage FET to drive the big FET's gate. They're
cheap and it doesn't take much (damn near nothing) to drive them. Use
a micropower opamp and you can get its supply voltage from a resistor
and a low-current shunt reference tied to the 400V rail (or even just
a resistive divider) The Zener is to make sure the big MOSFET's gate
voltage never goes higher than it's supposed to, WRT to the source,
R2 R3 is the 40:1 divider, and C1 is to keep the thing from
oscillating.

It cannot oscillate no matter what value you use for C1.
Study it carefully and I'm sure you can see why.

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Larry Brasfield]

"John Fields" <jfields@austininstruments.com> wrote in message
news:fg81411s2adq8t2bhtil31jgjqmhjbubua@4ax.com...

On Tue, 22 Mar 2005 12:37:39 -0800, "Larry Brasfield"
donotspam_larry_brasfield@hotmail.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:emr041dnld7pmj6v7emf5bdsvng962tqgv@4ax.com...
On Tue, 22 Mar 2005 12:32:16 -0600, Michael Noone
mnoone.uiuc.edu@127.0.0.1> wrote:
...
+400V>--+-----+---D S---+----------+-------->>--+
| | G | | |
| | | [ZENER] | |
[R1] [R2] | |K | |
| | +-----+ | |
| | | | |
| +-----+ | |
| | | |
+-------------------+ Vin [R2] |
| | | | | |
| D /-|--+ | [RL]
|K G---< | | |
[REF] S \+|-------+-----+ |
| | | | | |
| | | [R3] [C1] |
| | | | | |
GND>----+-----------+-------+--------+-----+-->>--+


Use a little high-voltage FET to drive the big FET's gate. They're
cheap and it doesn't take much (damn near nothing) to drive them. Use
a micropower opamp and you can get its supply voltage from a resistor
and a low-current shunt reference tied to the 400V rail (or even just
a resistive divider) The Zener is to make sure the big MOSFET's gate
voltage never goes higher than it's supposed to, WRT to the source,
R2 R3 is the 40:1 divider, and C1 is to keep the thing from
oscillating.

It cannot oscillate no matter what value you use for C1.
Study it carefully and I'm sure you can see why.

---
Typical behavior for you. As the erroree, when you find what you
think is an error, instead of simply stating what you think it is that
makes it an error, you hold back and try to get some mileage out of it
by requiring a lot of work to be done by whom you consider to be the
errorer.

The post you quoted is one I canceled a couple of
minutes after hitting send. I mistakenly read your
upper MOSFET as a reversed P-channel device,
assuming, incorrectly, that you intended to produce
the 400V output first mentioned by the OP. As I
was reading your schematic, filling in the missing
polarity, it looked like a bistable latch. And if that
was what you had drawn, (or meant to draw), it
would have taken little time to spot it.

In this case, good catch, but... the larger C1 becomes, the greater
the output ripple becomes, until it starts to look like an
oscillation. The best C1 is no C1, according to bitethedust.asc which
you can find on abse and which you can run if you've downloaded
LTSPICE

I'm game. It's not showing up on my newserver
in alt.binaries.schematics.electronic . Can you
either email it or state what part values and
transistors you used? Or post, the .asc, which
is ASCII, so can be pasted into a post.

I presume your comments apply to my post of
12:50, where I asked about loop gain shifts
and dominant poles. Since you elect to not
answer that, I want to simulate your circuit
and see for myself.

Where did the output ripple come from? I can
see no source for it in your schematic other
than an oscillation. I'm about 95% confidant
that it will oscillate until C1 becomes huge.
The only question is where the limiting occurs.

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.

 

[Genome]

"John Fields" <jfields@austininstruments.com> wrote in message
news:fg81411s2adq8t2bhtil31jgjqmhjbubua@4ax.com...

On Tue, 22 Mar 2005 12:37:39 -0800, "Larry Brasfield"
donotspam_larry_brasfield@hotmail.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:emr041dnld7pmj6v7emf5bdsvng962tqgv@4ax.com...
On Tue, 22 Mar 2005 12:32:16 -0600, Michael Noone
mnoone.uiuc.edu@127.0.0.1> wrote:
...
+400V>--+-----+---D S---+----------+-------->>--+
| | G | | |
| | | [ZENER] | |
[R1] [R2] | |K | |
| | +-----+ | |
| | | | |
| +-----+ | |
| | | |
+-------------------+ Vin [R2] |
| | | | | |
| D /-|--+ | [RL]
|K G---< | | |
[REF] S \+|-------+-----+ |
| | | | | |
| | | [R3] [C1] |
| | | | | |
GND>----+-----------+-------+--------+-----+-->>--+


Use a little high-voltage FET to drive the big FET's gate.
They're
cheap and it doesn't take much (damn near nothing) to drive them.
Use
a micropower opamp and you can get its supply voltage from a
resistor
and a low-current shunt reference tied to the 400V rail (or even
just
a resistive divider) The Zener is to make sure the big MOSFET's
gate
voltage never goes higher than it's supposed to, WRT to the
source,
R2 R3 is the 40:1 divider, and C1 is to keep the thing from
oscillating.

It cannot oscillate no matter what value you use for C1.
Study it carefully and I'm sure you can see why.

---
Typical behavior for you. As the erroree, when you find what you
think is an error, instead of simply stating what you think it is
that
makes it an error, you hold back and try to get some mileage out of
it
by requiring a lot of work to be done by whom you consider to be the
errorer.

In this case, good catch, but... the larger C1 becomes, the greater
the output ripple becomes, until it starts to look like an
oscillation. The best C1 is no C1, according to bitethedust.asc
which
you can find on abse and which you can run if you've downloaded
LTSPICE

--
John Fields

John, that is piss poor. Whilst Larry might not have the bananas to
tell you why he will probably sweat buckets coming up with some
'reasons'. You have done yourself and Spice a big unfavour.

DNA

 

[Genome]

"John Fields" <jfields@austininstruments.com> wrote in message
news:6jg1415ct80cmsvqujrc60qqsbjqn2945h@4ax.com...

On Wed, 23 Mar 2005 00:18:43 GMT, "Genome" <ilike_spam@yahoo.co.uk
wrote:


John, that is piss poor. Whilst Larry might not have the bananas to
tell you why he will probably sweat buckets coming up with some
'reasons'. You have done yourself and Spice a big unfavour.

---
I'm sorry to hear that and, since I respect your opinion, I'd like
to
hear where I've gone awry.

--
John Fields

OK, not that I'll nail it but....

You drive your control mosfet through a resistor from your error
amplifier. That resistor forms a pole with the mosfets input
capacitance.

The drain of your control mosfet drives the pass mosfet. The control
mosfet acts as a current sink. Your pass mosfet has its gate
capacitance. That gives you another pole, current driving a capacitor.

At some point your system goes second order and will therefore be
unstable.

You add your compensating capacitor at the input to your error
amplifier and you drive it third order and things get worse.

Your op-amp model includes the line

Avol=1Meg GBW=10Meg Slew=10Meg

It's a first order model in itself, those poles are adding up. Then
you don't add a local loop around that op-amp and run it balls to the
wall.

If you probe the output of the op-amp in your spice model then you
will see that it's bouncing up and down.

OK, that's not exhaustive and I've not suggested any solutions but,
there you go.

Oh, and a pre-emptive...... Fuck off Larry.

I'm off to bed.


DNA

 

[John Fields]

On Wed, 23 Mar 2005 13:20:02 -0600, Michael Noone
<mnoone.uiuc.edu@127.0.0.1> wrote:

John Fields <jfields@austininstruments.com> wrote in
news:g0k24158d9glfoqdgf0o5jcmglinvdmevj@4ax.com:

On Wed, 23 Mar 2005 01:17:04 -0800, "Larry Brasfield"
donotspam_larry_brasfield@hotmail.com> wrote:


The prophesy was: John's circuit "will oscillate".

---
And it did. Big deal. It's now fixed, and I can only surmise that
since you didn't have your big gums flapping something to the effect
of: "...and here's a fix that even Fields should have known about,
blah, blah, blah..."

If you can get your sorry ass over to abse and download the file you
might learn something, even though you'd never admit it.

Goodbye for now.


Hi Mr. Fields - could you post what the corrected version of your circuit
is? Thanks so much for your help,

---
Sure. I'd be happy too. Matter of fact, since it's just text I'll go
ahead and paste it in here:


Version 4
SHEET 1 1052 680
WIRE -192 240 -192 0
WIRE -192 432 -192 320
WIRE -192 496 -192 432
WIRE -16 0 -192 0
WIRE -16 16 -16 0
WIRE -16 112 -16 96
WIRE 48 0 -16 0
WIRE 128 112 -16 112
WIRE 128 112 128 48
WIRE 128 192 128 112
WIRE 128 432 -192 432
WIRE 128 432 128 288
WIRE 208 272 176 272
WIRE 320 272 288 272
WIRE 320 272 320 192
WIRE 352 272 320 272
WIRE 384 240 384 144
WIRE 384 432 128 432
WIRE 384 432 384 304
WIRE 416 192 320 192
WIRE 512 0 144 0
WIRE 512 32 512 0
WIRE 512 288 416 288
WIRE 512 288 512 112
WIRE 512 320 512 288
WIRE 512 432 384 432
WIRE 512 432 512 400
WIRE 560 192 480 192
WIRE 560 256 416 256
WIRE 560 256 560 192
WIRE 592 256 560 256
WIRE 880 256 672 256
WIRE 880 288 880 256
WIRE 880 432 512 432
WIRE 880 432 880 368
WIRE 992 144 384 144
WIRE 992 288 992 144
WIRE 992 432 880 432
WIRE 992 432 992 368
FLAG -192 496 0
SYMBOL voltage -192 224 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V1
SYMATTR Value 300
SYMBOL res -32 0 R0
SYMATTR InstName R1
SYMATTR Value 1e6
SYMBOL res 304 256 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 32 56 VTop 0
SYMATTR InstName R2
SYMATTR Value 1000
SYMBOL Opamps\\UniversalOpamp 384 272 M0
SYMATTR InstName U1
SYMBOL res 496 16 R0
SYMATTR InstName R3
SYMATTR Value 1e6
SYMBOL res 496 304 R0
SYMATTR InstName R4
SYMATTR Value 34483
SYMBOL voltage 992 272 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V2
SYMATTR Value 12
SYMBOL voltage 880 272 R0
WINDOW 123 0 0 Left 0
WINDOW 39 0 0 Left 0
SYMATTR InstName V3
SYMATTR Value 10
SYMBOL nmos 176 192 M0
SYMATTR InstName M1
SYMATTR Value IXFX90N30
SYMBOL nmos 48 48 R270
SYMATTR InstName M2
SYMATTR Value IXFX90N30
SYMBOL res 688 240 R90
WINDOW 0 0 56 VBottom 0
WINDOW 3 38 55 VTop 0
SYMATTR InstName R5
SYMATTR Value 10k
SYMBOL cap 480 176 R90
WINDOW 0 0 32 VBottom 0
WINDOW 3 32 32 VTop 0
SYMATTR InstName C1
SYMATTR Value .1e-6
TEXT -226 520 Left 0 !.tran 0 .1s 0s .1s



--
John Fields

 

[John Fields]

On Wed, 23 Mar 2005 10:50:22 -0800, "Larry Brasfield"
<donotspam_larry_brasfield@hotmail.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:8n7341pqags1l6l9htraduvcua0509euh9@4ax.com...
On Tue, 22 Mar 2005 12:50:32 -0800, "Larry Brasfield"
donotspam_larry_brasfield@hotmail.com> wrote:

"John Fields" <jfields@austininstruments.com> wrote in message
news:emr041dnld7pmj6v7emf5bdsvng962tqgv@4ax.com...
+400V>--+-----+---D S---+----------+-------->>--+
| | G | | |
| | | [ZENER] | |
[R1] [R2] | |K | |
| | +-----+ | |
| | | | |
| +-----+ | |
| | | |
+-------------------+ Vin [R2] |
| | | | | |
| D /-|--+ | [RL]
|K G---< | | |
[REF] S \+|-------+-----+ |
| | | | | |
| | | [R3] [C1] |
| | | | | |
GND>----+-----------+-------+--------+-----+-->>--+


Use a little high-voltage FET to drive the big FET's gate. They're
cheap and it doesn't take much (damn near nothing) to drive them. Use
a micropower opamp and you can get its supply voltage from a resistor
and a low-current shunt reference tied to the 400V rail (or even just
a resistive divider) The Zener is to make sure the big MOSFET's gate
voltage never goes higher than it's supposed to, WRT to the source,
R2 R3 is the 40:1 divider, and C1 is to keep the thing from
oscillating.

What do you think the maximum output will be and
how does that compare with the "requirement"?

Would you increase C1 until it formed the dominant
pole in that loop?

Where do think that would be, considering where the
the previously dominant pole is (likely to be)?

How much loop gain variation would you expect to
see as the operating point changes?

---
For the answer to all of your questions, if you've taken the trouble
to download LTC's excellent simulator, run bitethedust.asc which you
can find at abse under the subject: "Bite the dust, asshole"


Quite a few points in one sentence, so I will answer them
in order, with a number to deliniate them.

1. Using simulation is not the right place to answer those
questions, especially when considering a set of topologies.
The simulator can be used to confirm (or refute) one's
understanding of a circuit, but it shares many of the pitfalls
of prototypes. It is a way of seeing how a specific
collection of components, with a specific set of parameters
and values, will behave. (And keep in mind, those parts
may correspond to no real part if the models are faulty.)
Saying "My circuit is good!" because you see something
you wanted to see out of a simulation is folly.

---
If, for some reason, you feel compelled to perform an in-depth, hand
analysis of the circuit, then by all means do it and report back to
me with what you find. Also, if you think that simulation isn't the
way to go, then I suggest you fly your reasons by some of the folks
who make a living doing simulation and see how far you get. I'm sure
Jim Thompson, for one, will see the error of his ways and join you on
the bench with a good ol' Weller soldering gun and a roll of 30-70
solder in hand just champing at the bit to go to work on your newest
project. And, you put down simulation while in nearly the same breath
stating that you found that my circuit oscillated _during_ simulation,
LOL!!! That, AFTER you declared, pre-simulation, that there was NO
WAY my circuit would oscillate regardless of the value of capacitance
on the opamp input. Amusing how you just can't seem to keep your foot
out of your mouth...
---

2. I have used LTSpice for a few years for quick
and dirty work.

---
So what did you think my circuit was? Something _not_ quick and
dirty? You're a joke.
---

3. I did acquire your strangely named sim file. It
is a vigorous oscillator. If you took the output
from the op-amp with suitable limiting, you could
use it as a crude VCO.

---
"If frogs had wings" again?
See above, LOL!
---

4. Name-calling is the recourse of those who find
it difficult to formulate a rational argument.

---
True or not, _you_ still remain an asshole.
---

Here are some short answers to my questions,
evident from a very brief analysis (of your posted
circuit which had no values or part types)

---
I showed no values or part types because it was my intent to present a
topology for consideration, not a fully fleshed out, tested and
guaranteed circuit. To someone skilled in the art that would have
been readily apparent. You, however, even mistook the pass transistor
for PMOS even though the drain terminal "D" was clearly shown as being
connected to the high-voltage supply positive.
---

confirmed by watching your oscillator with SPICE
(with the quoted questions copied from above):

---
Perhaps, because of the vagaries of simulation, it was an artifact?
---

What do you think the maximum output will be and
how does that compare with the "requirement"?

The requirement was 0 V to +400 V out. The
above schematic necessarily produces less than
that, subtracting at least a PMOS gate threshold.

---
Trivial to fix; merely increase the source voltage as required for the
headroom needed.

NMOS. Old habits die hard, huh?
---

The simulation does much lower due to part selection
apparently limited to the LTSpice standard library.

Would you increase C1 until it formed the dominant
pole in that loop?

That is the only way to make the circuit stable, but
the response becomes so slow that simulating it is
a challenge. (a challenge I had no patience for)

---
The _only_ way? Methinks your naivete is showing. You apparently
haven't seen the circuit modification performed after Mr. Genome so
kindly critiqued my circuit. Check it out and run the simulation.
It's on abse under "Bite the dust, asshole", just like last time.

--
John Fields

 

[Fred Bloggs]

Larry Brasfield wrote:

"Fred Bloggs" <nospam@nospam.com> wrote in
message news:4243A767.4000508@nospam.com...

Larry Brasfield wrote:

"Genome" <ilike_spam@yahoo.co.uk> wrote in message
news:m9y0e.1156$kj5.480@newsfe6-gui.ntli.net...

[snip]

If you want to measure loop gain and phase then you use the method
shown.

Break the loop with an AC voltage source and plot V(B)/V(A). There may
be some caveats about impedances but I'm sure you'll get the general
idea.

If *I* want to measure? What do you want? (And
do remember that threshold problem. I cannot even
imagine, let alone suggest, how to solve that. ;-)

In most of the circuits, your main interest has been stability- and now it turns out, you have no idea of how to use SPICE to
measure it.


Illogical. You cannot logically infer, from my declining
to play a little game with Genome, that I lacked the skills
needed to analyze his circuit. You have confused absence
of evidence with evidence of absence.

On the contrary, based on your past reaction to simpler circuits, such
as the ridiculous OP submission as well as JF's circuit, characterized
by rampant simulation and incredible excess of meaningless verbiage, it
is a slam dunk that you find no such facility with Genome's circuit. By
what "logic" would one abandon the proposition that Larry Brasfield,
show off and pretentious narcissist at large, never misses the
opportunity to demonstrate superiority , when this behavior pattern has
been unfailingly consistent? Answer me that.

[More venal speculation cut.]


You have been measuring the closed loop response.

I don't recall that with "your" circuit.

That is a lie- because you stated that it used the MOSFET gs capacitance for dominant pole compensation and may have problems....


Hmm, so your claim is that one cannot spot a
dominant pole without "measuring".

I claim no such thing, my statement was a paraphrase of your ridiculous
initial commentary.

That says a
lot, Fred. I spotted it by simply looking at the
circuit topology and doing a fairly simple analysis.
And I do not recall saying the compensation had
problems here.

Oh you did? Would sure love to see that analysis- doesn't take an eagle
eye to spot the Cgs charged through a current source is going to dominate.

(I have no idea
whether it is yours or not.) I never looked at it with
enough care to get that far. I never saw anything to
make me think it might be or become real.

That is because you have very little comprehension of it.


Illogical. These sorts of things appear to float right
over you, so I will spell it out: Genome wished to
resume a game which only peripherally involved
circuit analysis. I declined to play for reasons
completely unrelated to electronic skills.

I don't why you should, you seem perfectly willing to write 10,000 words
of bs trying to salvage your sorry-ass from previous errors and misconduct.

 

Seems like a fair assessment. On the other hand I shouldn't be too
critical
of him since he did use his grey matter to fashion something that
evidently
does function, and in fairness his background probably isn't in
electronics.
Kudos to the developer even if I wouldn't do the same thing myself.

The inventor was out $800 and was not willing to get 'burned' again.
For $25 he claims to get slightly more power that is possible with PWM.
Is that factual?


For a non-elctonicer, replacing brushes is much simpler than cracking
open a Curtis controller and trying to repair it.


BoyntonStu

 

Fritz Schlunder wrote:

stu@aaronj.com> wrote in message
news:1111940110.462051.140910@o13g2000cwo.googlegroups.com...

Kudos to the developer even if I wouldn't do the same thing
myself.

I think so too. And I'd say his design works - though I think the
claims made are, if not factually/legally wrong, certainly blatantly
misleading.

OK no, I stand corrected, "AND IT'S REALLY PRACTICAL!" is clearly not
true.

"the little Opel' really has some get-up-and-go"

maybe be legally true claim, but plainly misleading. Ie only true for
the most miniscule values of 'some'. A vehicle like that takes minutes
to get upto a reasonable speed, is unable to accelerate away from
problem situations, and is forever limited to little more than the
slowest speed bits of a journey, ie corners.

The inventor was out $800 and was not willing to get 'burned'
again.
For $25 he claims to get slightly more power that is possible with
PWM.
Is that factual?

For a non-elctonicer, replacing brushes is much simpler than
cracking
open a Curtis controller and trying to repair it.

Quite a good idea actually - this thread shows even tronic designers
cant choose the cheaper more reliable design.

Its very old tech, but thats no reason to reject it. It was 25 instead
of 800, an important consideration for any engineer, car alts are
reliable, ditto fan motors, and using a carbon copper switch means near
zero v drop - a good design really, and clearly a good choice in the
70s.

It appears the complete article can be accessed here:


http://www.motherearthnews.com/library/1979_July_August/An_Amazing_75_MPG_Hybrid_Electic_Car

As for the rest of the performance claims, I would say they are
rather
fanciful. Five horsepower just isn't enough juice to push a normal
car on
level terrain at 50mph.

Read again.

1. The gas motor puts out 5hp, and the batteries will put out a lot as
well.

2. The car is 50lbs heavier than it was with a gas engine and clutch,
so it has quite a bit of battery in it, not ordinary car batts.

3. The article sells plans and may mislead the unwary, ie 90 may be
only achieved on the steepest straight downhill stretch of road on the
planet, and 50 may only be achieved for short times under favourable
conditions.

Four regular automotive batteries would not be able
to supply too tremendously much more power than 5hp,

"the engineer installed four 12-volt, heavy-duty automobile
batteries-in series" not regular ones. I'm thinking very heavy duty,
like 100-200 Ah. The car gained 50lbs.

and they wouldn't last
very long at all.

yup, as is implied in the article.

Additionally they would require replacement very quickly
since automotive batteries aren't intended for that kind of use.

yes, a backyard tinkers design. I wonder if one could improve that to
some extent by refilling them with gel electrolyte. Still wont give
adequate lifetime though, or anywhere near.

Expecting
a top speed of 90mph is also fanciful. The 1.0L Geo Metro has a
rated
maximum output of something around 55hp if I recall correctly. That
car,
which only weighs 1800 lbs and has very small tires for high
efficiency has
a top speed of around 80ish miles per hour on level terrain.

You dont need anything approaching 55hp to hit 90. A 30hp peak rating
engine, run at just over half speed, so roughly around 15-20hp, will
take a 1 tonne car to 85mph on the level, and more downhill. But... it
will take minutes to get there, as the excess power for acceleration
dwindles to zero at those speeds.

A smaller car doing 55 will need very much less.

I suspect the car described in the article would be lucky to sustain
25mph
on level terrain, with a total inability to go up even the smallest
of hills
at any speed.

One human can push a small car like that at 10mph, on the level. Its
acceleration where more serious power becomes needed.

Having driven wildly underpowered vehicles, there are tricks. Hills:
take a run up, and most of the power you need comes from the inertia of
the vehicle.

This car shoudl meet its claims just about, but with many gotchas. The
prime reason for 75mpg is simply the dangerously low power output.
Hybrid tech helps too. But the driving experience would be dire. The
designer consider a clutch unnecessary for example. IOW if you stop the
car just once without going down thru the gears youve got your first
issue. And you have to get the gearwheel speeds dead right at every
single change. Fun.


Runnable, sure, but not workable on todays roads, ones with other cars
on them. Might have been fit for very occasional daring use out in the
middle of nowhere in the 70s, underpowered to the point of dangerous.


NT

 

Thanks for a well thought out and quite balanced response.

I wonder how such a device would allow the vehicle to stIn other words;
with the battery 'ON' how does the commutator come to rest with the
current 'OFF'?

Today, how does one build a really cheap/simple mosfet 'pulser'
(not PWM)?

What I mean by my question is this. Assuming a 150 Amp/100V mosfet is
available as a replacement for the carbon/copper switch, what is the
simplest way to modulate the mosfet switch?

BoyntonStu

 

[Richard H.]

Nico Coesel wrote:

However, in practice, I've never seen an installation implement other
than always-on. (IIRC, blowing the cobwebs out, this is the Q.921 link
signaling, which is typically kept alive regardless of upper-layer Q.931
sessions.)


Over here all public network ISDN2 links are shut down after 30
seconds. Also, 99% of the connections are point to multi-point. For
instance, I have 3 telephones and a fax connected to one ISDN line
each having a different phone number.

Understood. We seem to be talking about different levels within the
connectivity.

When an ISDN endpoint is physically connected and powered-on, a
link-level heartbeat is established with the immediately adjacent ISDN
switch. This takes several seconds to establish, and is maintained
independently of any calls (voice or data). This is the "always on" I'm
referring to.

The minimum service here is "2B+D" BRI service, which is two 64K
"bearer" channels and a 16K "data" (control signaling) channel. Usually
1 phone number per channel, and the call gets directed to the data vs.
POTS port depending on whether it's a voice call type. More numbers can
be setup, and some endpoints can map these to POTS distinctive ringing
(how my home office is setup).

Aside from having multiple numbers / channels per line, I understand
there's a way to connect multiple ISDN endpoint devices to a single
physical circuit (not normal with ISDN). An example I recall is
multiple POS terminals sharing the one D channel for low-volume
credit-card authorizations. I've never seen this done in practice -
typically, there's just one ISDN terminating device, which muxes the
downstream connectivity.

IIRC, it takes several seconds to establish Q.921, so this wouldn't be
friendly to many voice applications.

Several seconds? More like 100ms (depending on resources). Besides, on
an ISDN2 link the incoming setup message is send before layer2 is
actually initiated.

There are multiple protocol stacks involved here, so multiple "layer
1...3" references. ISDN layer 2 (Q.921) is always-on between the two
endpoints of the physical wire; ISDN layer 3 (Q.931) is the call setup
protocol, which does establish very quickly; a call appears to IP as a
Layer 2 (link layer) service connecting to a remote IP router.

 

stu@aaronj.com wrote:

Thanks for a well thought out and quite balanced response.

I wonder how such a device would allow the vehicle to stIn other
words;
with the battery 'ON' how does the commutator come to rest with the
current 'OFF'?

My best guess is the fan motor + rewired alternator stay spinning as
long as the ignition switch is on. At least thats how I'd probably do
it. Taking foot off the gas pedal will mean no current to the main
motor during stopping.


NT

 

[Bill Bowden]

One very good designer I knew (he's now deceased) not
only adamantly required resistors on unused inputs, but
edicted, "No system shall contain a one-shot." ;-)

Why not just connect the unused inputs to some output, so
the input is terminated, and you don't need the resistor?

-Bill

 

[Bill Bowden]

One very good designer I knew (he's now deceased) not
only adamantly required resistors on unused inputs, but
edicted, "No system shall contain a one-shot." ;-)

Why not just connect the unused inputs to some output, so
the input is terminated, and you don't need the resistor?

-Bill

 

[Larry Brasfield]

"Active8" <reply2group@ndbbm.net> wrote in message
news:d2ic4q.3ac.1@active8.fqdn.th-h.de...

On Thu, 31 Mar 2005 12:33:22 -0800, Larry Brasfield wrote:

"Active8" <reply2group@ndbbm.net> wrote in message
news:d2h34o.3a4.1@active8.fqdn.th-h.de...
On Thu, 31 Mar 2005 11:33:49 -0800, Larry Brasfield wrote:
"Active8" <reply2group@ndbbm.net> wrote in message
snip

=========== screen scrape begins ==============
[C:\Play]
dir *.url

Volume in drive C is unlabeled Serial number is CCCE:6A5D
4NT: (Sys) The system cannot find the file specified.
"C:\Play\*.url"
0 bytes in 0 files and 0 dirs
168,907,882,496 bytes free
^^^^^^^^^ important thing I missed

[C:\Play]
echo "1234567890123456789012345678901234567890" > x.url

[C:\Play]
dir *.url

Volume in drive C is unlabeled Serial number is CCCE:6A5D
Directory of C:\Play\*.url

3/31/2005 9:37 44 x.url
44 bytes in 1 file and 0 dirs 4,096 bytes allocated
^^^^^^^^^^ WTF?

That means the directory listing specified did not include
any subdirectories. (Nothing that strange, really.)

168,907,882,496 bytes free
^^^^^^^^^ important thing I missed

[C:\Play]
type x.url
"1234567890123456789012345678901234567890"

[C:\Play]

=========== screen scrape ends ==============

Note the similarity of the 12 digit numbers. No space was
taken beyond using an already-allocated MFT entry.

You might have said, "check the 'bytes free' line" and avoided
confusion.

I thought there was clue enough in "No space was taken
beyond using an already-allocated MFT entry." I made
every effort to present my argument clearly and cannot
take responsibility for your election to ignore part of it.
That said, however, I agree that your version might have
been clearer.

Yet you snipped info and instead of just saying "<snip>",
you had to call it "frivolity".

If you review that post of mine, you will see that my cut
comment was entirely accurate. It mentioned only a
resolved MFT definition and "bubble frivolity". The
material that went missing under that comment did
not contain any information that would have helped
clarify the remaining issues. I try to quote accurately,
so please try to be accurate in your accusations of
quoting shenanigans.

snip

So...

1. Why does your shell print 4,096 bytes allocated? Mine doesn't.

I'm using 4NT from JP Software. ( http://www.jpsoft.com/ )
It is a CLI shell with considerably higher utility and lower
frustration than the abomination known as cmd.exe .

But the properties applet does, except it's worded as "size on
disk".

In a very real sense, (opportunity cost), that report is
accurate. It just does not contravene my claim about
space relative to a merely existent file.

*********
Volume in drive C has no label.
Volume Serial Number is 7862-9D07

Directory of C:\0

04/01/2005 02:08 AM 29 x.url
1 File(s) 29 bytes
0 Dir(s) 1,196,507,136 bytes free
**********

2. What version of winders are you using? I tested this out here and
the NTFS is working as advertised, but FAT32 is doing that which I
expected - wasting space. Your shell is outputting the dir command
differently. Just curious.

The OS is Windows XP, SP2.

My comments up to now pertained only to NTFS. For
many reasons, FAT32 is a space waster. (For example,
NTFS supports hard links, an occasional space saver.)

As far as I can see, it supports
my limited claim and does not contradict it. If you see otherwise,
please be more specific as to what claim of mine it disproves.

The line I highlighted diverted my focus from the one that mattered.

I assure you my screen scrape was intended only to help
get to verifiable facts. (And I included the whole thing,
verbatum, without regard for prospective diversion.)

....

That's what defrag does. It groups unused clusters
blocks) at the ends of fragged files and makes the data contiguous.
That frees up clusters in cases of severe fragmentation.

That is not what defrag does. It makes the data more
contiguous, (not necessarily completely contiguous) and
it merely reassigns the file content to a new set of clusters
having the same size as the previous set.

Think about that. If you have 100 frags of a file and each frag does
not completely fill the last cluster, you'll free up clusters by
defragging.

Your antecedent does not occur. File content completely
fills all but the last cluster. There is no mechanism for
tracking partial cluster usage other than the recorded
file size, and that predicts the integer number of clusters
used and the fraction of the last cluster used. If you do
not believe this, please provide some evidence regarding
partial cluster usage except at the end of a file.

X = one full cluster of data
x = exactly 1/2 cluster of data

frag1: XXXX x frag2: XXXX x
^ ^ takes a whole cluster

so that's 2 frags occupying 10 clusters

defrag: XXXX XXXX X

count 9 clusters. Thus, defragging freed one cluster.

Do you have any evidence that any cluster other than the
last can be only partially used in either FAT32 or NTFS?
Your argument seems to depend on such a proposition,
but I have never heard of it except from you here.

In order to make the file contiguous, it often needs to
move the next file somewhere else so it can put free clusters at the
end of said file.

I've studied the on-disk format for FAT file systems,
(including CPM), and never seen anything that would
facilitate the operation you just described. And as you
can see from the reference I provided, NTFS does
not work that way either.

Like I said, I vaguely remember the "file in the MFT" feature of
NTFS. It just looked like it wasn't living up to the claim.

My comment related to your "partially used cluster(s)
not at end of chain" claim.

I think that, until there is some evidence to support that
claim, this subargument can go nowhere informative.

--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.