Driver to drive?

krw wrote:
In article <48fc31bc$0$25384$8404b019@news.wineasy.se>,
david@westcontrol.removethisbit.com says...
krw wrote:
In article <6m187dFee7g6U1@mid.individual.net>,
dirk.bruere@gmail.com says...
krw wrote:
In article <6luv1iFe90meU1@mid.individual.net>,
dirk.bruere@gmail.com says...
JeffM wrote:
snip
I cannot understand why anyone would buy MS products when this is free.
Because, unless you are doing trivial work, it isn't compatible with
the other 99.9% who would rather pay for software.
We've been using a mix of OOo (mostly the <http://go-oo.org/> version at
the moment) and MS Office at my company since OOo was still Star Office.
There are still a few machines that have MS Office, which is useful
for the odd difficult document (sometimes there are layout issues when
importing MS documents with complex tables or numbering, and word
documents with embedded excel spreadsheets don't work).

So you admit that OOo is incompatible with complicated M$O
applications, particularly Excel spreadsheets.
It is certainly incompatible with Word documents with embedded Excel
documents. But then, so is MS Word if you don't have the whole Office
pack, and so are different versions of MS Office. Perhaps this will
change as MS is forced to provide more documentation on their formats.
But either way, it makes no practical difference to me - I've rarely had
to look at such documents, and in most cases it was just someone being a
smartass.

Of course, different people use programs in different ways - if you make
a lot of use of advanced features such as macros and integration between
programs, then you'll have a lot more trouble converting to a different
program suite (and that includes converting *to* MS Office, as well as
converting away from it). Pick the best tool for the job - OOo is the
best office pack for my office, but that doesn't mean it's the best for
everyone.

But it's been a
good while since we bought any new MS Office licenses. We choose OOo
for a number of reasons:

Irrelevant.
Not really. OOo is an active choice for us, not just a "free" option.

It's a standard, and it uses standard document formats.

It may use "standard" formats, but it is most certainly *not* a
standard. In particular Calc is really messed up.
It works fine as far as I've seen. I've had to help other users here
with occasional problems with Excel that were non-issues with Calc. But
if you don't like Calc, there are other programs that work with the
standard ODF formats (like KOffice - coming soon to Windows if you don't
like *nix).

I'm not suggesting everyone should switch to OOo - I am merely
explaining why it is the right choice for us, and could be the right
choice for others. I think the freedom of choice is important - that's
why it is a good thing that MS will support ODF (as long as they don't
try "embrace, extend, extinguish"), as it gives users more choice of how
to access their data.

It's better than newer MS Office for working with older MS Office documents.

Only if you have no clue what you're doing with M$O. OOo has horrid
spreadsheet compatibility (the main reason I cannot use it).
I've helped out customers who had old Excel 95 files that they could not
open in newer versions of Excel - I used OOo to open said files, and
re-save them in a newer Excel format. That's my personal experience -
obviously that's going to different from yours.

It works on any machine, any OS, any Windows version, any service pack.

Equally badly.

We can upgrade when as and when *we* want, not when some other company
dictates. And the upgrade is independent of everything else on the system.

I'm still using Office '97 (and OOo) at home and '03 at work. No
one is forcing me to "upgrade".

We don't have to install "security updates", or worry about macro
viruses (the only viruses we've had at our company were macro viruses).

You're lucky. Of course macros are a pretty important feature for
anyone using Excel for more than lists.
We're not lucky - we are careful and sensible. But we made the mistake
of trusting data files sent from an American partner company which
turned out to be infected.

Spreadsheets can do an enormous amount without bothering with macros -
the huge majority of users (of Excel, Calc, or any other part of either
office suite) have no concept of what macros are or how to use them.
Yet they make good use of the tools. If you find you need macros all
the time, then either you work regularly with much more advanced
spreadsheets than most users, or you haven't noticed the little
"function wizard" button.

We don't have to suffer a f***ed up software update system that can lock
up a PC for hours during automatic MS Office updates even though updates
were explicitly turned off.

Office doesn't force updates on me. Windows does (and that can be
turned off), but no office updates. At work, updates (to Windows)
are done at night. The automatic reboot pisses me off, but...
I've seen it happen (you can do some web searching if you want - it was
about a year ago, IIRC) - PC's with particular versions of Office got
stuck as a result of an update (despite automatic updates on Office
being turned off) which caused them to spend many hours at 100% cpu time
on the update process.

We can work together with our customers and partners that use OOo as
well as those that use MS Office.

Only if your customers are simpletons.
Yes, I'm sure you've found the reason why some people choose OOo.

We can freely mix and match languages for the interface and for
dictionaries.

We can export to pdf directly from OOo, giving much better pdf's than
you can get from MS Office + Acrobat Distiller, much faster.

There are many PDF printers available, beer-free.
There are also speech-free PDF printers
(<http://sourceforge.net/projects/pdfcreator/> being the one we use).
But just like Distiller, they work as printers. You lose information
such as links, clickable table of context, references, and indexes.
Distiller can get you some of that information, but it takes work. With
OOo, all you need to do is make proper use of paragraph styles (which
you should do anyway), and you get a fully structured pdf in a fraction
of the time.

Employees can install OOo freely, legally, safely, and easily on their
home machines.

Oh, and it's free.

Free isn't a very useful feature if it doesn't work. OOo Calc is
brain-dead.
I agree that the cost-price is a minor issue at this price level
(figuring out what licenses you need, and what licenses you have, can
cost more in time than the software cost itself). That's why I gave it
as the last reason.

If Calc doesn't work for you, pick something else. It works fine for
me, and others at my company, and millions of others around the world.
I'm sure it has its limits, and I'm sure there are features in Excel
that Calc doesn't have, and that a certain proportion of users want
those features - that certainly applies to the pdf generation feature of
Calc that does not exist in Excel.

I'm curious - what is it that Excel can do that Calc cannot? Is it just
the import/export of complex Excel documents with macros, or are there
things that you simply cannot do correctly with Calc? As I said, I have
had no problems - but I don't use it very much. Other people here have
no problem using Calc for budgets, analysis, planning, charting, and all
sorts of other uses (no macros that I know of, however).

Even if OOo and MS Office were the same price, I'd still prefer OOo. I
have a number of licenses for MS Office (or at least MS Word) that came
"free" with PCs over the years - I've never bothered installing them.


Well, a number of governments think different.
^ly

So? The *fact* is that OO is not compatible past the rudiments,
with M$. It matters not, why or who is (in)compatible with whom.

And the way I heard it, it is MS who has been forced into compatibility
with ODF
Nonsense. M$ doesn't care about compatibility with M$.

You might have a typo there, but it's true that MS Office has poor
compatibility with older MS Office versions!

No, I don't have a typo there. I have *no* love for M$. In this
case, there is no good alternative (to Excel).

MS certainly don't *care* about compatibility with anything non-MS. But
they *do* care about large markets. ODF is an ISO standard, and is the
mandated standard for steadily more governments and official bodies
around the world. OOXML is a flop - MS are aware of how badly they
messed it up, and what a PR failure it was. The continuing process of
ISO ratification serves only to destroy ISO's reputation - it will not
make OOXML a real standard. Added to this, the OOXML quasi-standard at
ISO is not the same as the OOXML used by the latest MS Office versions.
In fact, MS sees it as easier to implement ODF support than to support
ISO-OOXML (perhaps because the former is a proper specified and
documented format). MS has made a tactical withdrawal on formats, and
wants people to standardise on ODF using MS Office (once they've got the
next version out, of course).

sheesh
MS are rapidly losing their lock-in with office file formats - ODF is
increasingly popular, and OOo does everything the majority of office
suite users need. Strong support for ODF is the only way they have a
chance to regain those lost users.
 
Adrian Tuddenham wrote:

Eeyore wrote:
Adrian Tuddenham wrote:
kevin93 <kevin@whitedigs.com> wrote:
Eeyore > wrote:

Did you know theKT66was originally designed for radar PPI
deflection coils ?
Graham

Seems unlikely as it was introduced in 1937 according to Wikipedia.

More likely to have been the EL38, that had a top-cap anode which
allowed it to withstand the high peak voltages of an inductive load.

My source was an IEEE book about valve development for radar.
I'll have to drag it out and re-read.

I'll be interested to hear what was available in 1937. There is a vague
possibility that I may have to build an 'authentic' amplifier for an
electronic/electromechanical organ of that vintage. I know they used
KT66s in the post-war models, but haven't been able to find out about
the pre-war ones. It is possible they used the same amplifier for both,
in which case I just copy the later one, for which I have the drawings.
KT66s (and 88s) have always been well regarded for audio. Don't ask me why,
it's a tubophile thing. They like the 300B too (very linear transfer curve
IIRC) but it has a directly heated filament/heater so not the simplest to
use.

I reckon you'll be fine with the post-war design.

Graham
 
JosephKK wrote:

Eeyore wrote:
JosephKK wrote:
Eeyore wrote
bill.sloman@ieee.org wrote:
"Jon Slaughter" wrote:

I guess you guys don't know much about guitar amps?

That doesn't follow. What we do know is that it is lot cheaper to
distort a signal with semiconductors and subsequently amplify it with
semiconductors than it is to amplify and distort it with valves.

Wrong type of distortion. Compare the transfer characteristics. Tubes produce more
even-order harmonic distortion, transistors odd. And odd order sounds horrible.

That just gives the 'fuzz box' sound.

It is also dependant on circuit topology. Electrical efficiency has
always been part of the equations. Push-pull amplifiers are more
electrically efficient, they also produce more odd order harmonics. It
is quite unavoidable from the circuit topology itself.

Whilst you're correct about the output stage alone, you're neglecting the contribution
of the 'pre-amp' and driver stages where considerable even-order harmonics will be
produced by valves.

Also, a valve amp naturally 'soft clips' whereas a SS one will hard clip. This alters
the harmonic distribution of the THD, reducing the high-order content in the case of
valves. This is seriously audible and MUCH nicer to listen to.


Nor have i disagreed when those points were expressed. They are quite
true. In the long run i think i might use a valve preamplifier to get
the sound and a highly derated very linear post amp.
Several people have done this in the past. The name Phoenix comes to mind which was funded
by (I think by then) ex-members of the band Argent. That's the first I know of.

I suspect Marshall is doing something like this now too but I'm not up to date on their
stuff, it's not actual 'pro' audio, it's what we call MI (musical instrument) technology.

And for the masses we now have what's called prosumer. Near real pro kit performance at a
bargain price and usually in small sizes but more of a 'consumable' than real pro kit. Some
can be quite good actually. I've designed a fair few of that ilk myself.

Graham
 
"Michael A. Terrell" wrote:

Eeyore wrote:
Jan Panteltje wrote:
"Tam" wrote in

Real men build amps where the plates are at least cherry red. If they don't,
you are not pushing the envelope.

I have seen them melt the glass.

I have seen the plates melt.

That was a common failure mode in the early 6JE6 Horizontal output
tubes used in early US color TVs, I found several that developed a hot
spot on the plate, and the envelope melted, and the glass was pulled in
till it touched the damaged plate. All it took was the loss of
horizontal drive for a few minutes. It didn't take long for an improved
version to hit the market.
In this case it was a guitar tech mucking about with speaker leads while the bass
player was tuning up.

A nice white flash followed by an ever deepening red ! 4 dead KT88s and they were NOT
cheap. He had to pay for the repair in installments. I'm too nice to people like
that. Then again that band was a regular customer for our PA rig.

Graham
 
Robert Lacoste wrote:

"Eeyore" a écrit
Robert Lacoste wrote:
"Eeyore" a écrit

Me ? A PIC ? You must think I'm going mad !

No, it's for someone else I may work on a project with and he's into
PICs. He wants a little 8 pin jobbie with an onboard A-D. Currently
he's looking at a 16F220 IIRC. That only has an 8 bit A-D.

I reckon we need 12 bits off the top of my head but 16 would be nice.

Any suggestions ? I'm totally unfamiliar with their range and he's off
on dog-sitting holiday for 2 weeks.

Why not a PSoC from Cypress ? You can implement a 14 bit ADC in its
analog configurable blocs, and there are 8-pin devices in the family.

You mean semi-custom ?

We don't have those quantities.

No, the PSoC is a family of user-configurable mixed signal devices.
Somethink like a microcontroller plus an "analog fpga" in the same chip, and
as cheap as the majority of 8-bit micros. WIth the PSoC-Designer tool you
can simply drag & drop blocks like ADC, PGA, filters, etc. Give it a try...
Thanks, sounds interesting. Do they require a special programmer or is the
programming interface built into the chip as seems to be increasingly the case
even with 8051 type devices ?

Graham
 
JosephKK <quiettechblue@yahoo.com> wrote in
news:pnegf4tsc7op0d21lars8kmrok30auvevd@4ax.com:

On Wed, 15 Oct 2008 15:35:45 GMT, Robert <someone@nowhere.com> wrote:

Hello everyone,

A battery powered product is headed for “intrinsically safe”
certification. The main test documented in prior certificates uses
the open circuit voltage and short circuit current from the power
source to see if an explosive mixture of gases can be ignited. The
circuit capacitance is placed across the combination of a bench supply
and a limiting resistor for the test.

I am looking for information on the short circuit current for 9V and
AA batteries. This varies by manufacturer, model, and from battery to
battery. I would also like to hear if anyone has ever tested small
batteries for short circuit current.

Have a good day,
Robert

If you need an intrinsically safe level, please consider sealed
apparatus. Otherwise the limits are like 50 uA and 5 V at all times.
Moreover applications like explosimeters, are constrained to replacing
batteries in clear atmospheres.
This is a rework of an existing product that is already approved
intrinsically safe. Unfortunately, like many businesses, documentation
and history from the prior approval was not maintained.

The case is well sealed. Fortunately this redesign is just a new circuit
board and replacing the 9V battery with two AAs.

Robert
 
Jon Slaughter wrote:
"Anthony Fremont" wrote:
Frank Buss wrote:
James Waldby wrote:

movf mask,w ; (Only if mask is not in w already)
iorwf IND,r ; set bit
btfss updbyte, 5 ; check for set or reset
xorwf IND,r ; reset bit
continue nop

This is dangerous, if an interrupt is generated after the iorwf.

How so?

If an interrupt occurs before the reset then the state might not be
properly defined if the interrupt depends on the data.
Well duh, but that would be a logic error and that goes beyond the scope of
this discussion; we could make up scenarios like that all day. I was
thinking (well hoping) Frank had something special for us pertaining to the
PIC architecture.

Turning off interrupts for the modification will help but writing the bit
in one
go is best.
With all due respect, that's more a matter of opinion than one of fact as it
depends upon the specific application. If the ISR is dependant upon the
data that is currently being modified, then disabling INTs for a few
instructions [atomizing the update] is probably the best thing to do to,
unless your ISR can't handle the entry jitter. In that case, you need to
rethink the design. Otherwise, I don't see how an INT occuring at that
location can cause any harm if the ISR is properly saving and restoring the
program context before returning. Please elaborate Frank.
 
On Mon, 20 Oct 2008 08:24:36 -0500, "Anthony Fremont"
<nobody@noplace.net> wrote:

UltimatePatriot wrote:
mpm wrote:

Please make your check out to the Democratic National Convention, or
Planned Parenthood.
Or even "Joe the Plumber". Maybe it'll help him with his back-taxes.
Thank you.


Back taxes? You're an idiot. You believe all that bullshit the DP
started? You are one gullible dipshit then.

The guy owes back taxes,
Due to a messy divorce.

makes 40K/year, and isn't even licensed as a
plumber.
You don't have to be licensed if you're employed by a licensed plumber
who signs off on the work.

These aren't some trumped up rumors, they are matters of public
record.
[smirk]

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona 85048 Skype: Contacts Only | |
| Voice:(480)460-2350 Fax: Available upon request | Brass Rat |
| E-mail Icon at http://www.analog-innovations.com | 1962 |

I love to cook with wine Sometimes I even put it in the food
 
On Mon, 20 Oct 2008 14:13:44 +0100, Eeyore
<rabbitsfriendsandrelations@hotmail.com> wrote:

John Fields wrote:

Eeyore wrote:
John Fields wrote:
Eeyore wrote:
John Fields wrote:
Eeyore wrote:

You're a babe in arms in this discipline.

---
You wish.

I cut my teeth on audio and was designing and building bridge amplifiers
in the early '60's, even before RCA came out with them, as I recall.

The world has moved on John.

---
As have I, while you guys keep struggling to lower THD to limits which
are so far beyond the threshold of audibility that the point of the
exercise becomes ludicrous.

But it's FUN !

Where would you place the threshold (and what harmonic structure) of audible
THD ?

---
It depends:

http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GFRC,GFRC:2006-50,GFRC:en&q=harmonic+distortion+threshold+of+audibility

JF

I was interested in YOUR opinion though.
---
No, you weren't.

What you were interested in doing was trying to place yourself in a
dominant position at my expense, and I won't have it.

JF
 
On Mon, 20 Oct 2008 14:15:32 +0100, Eeyore
<rabbitsfriendsandrelations@hotmail.com> wrote:

John Fields wrote:

Eeyore wrote:
John Fields wrote:
Eeyore wrote:
John Fields wrote:
Eeyore wrote:

You're a babe in arms in this discipline.

---
You wish.

I cut my teeth on audio and was designing and building bridge amplifiers
in the early '60's, even before RCA came out with them, as I recall.

The world has moved on John.

---
As have I, while you guys keep struggling to lower THD to limits which
are so far beyond the threshold of audibility that the point of the
exercise becomes ludicrous.

But it's FUN !

---
So if it's fun for you and your clique it's OK, but if it's fun for
someone else, like Olivier, then you'll do your damnedest to try to make
him feel stupid instead of offering a helping hand?

But I have given him a helping hand by recommending the very best stage for the
job. The complementary emitter follower biased into full Class A. More efficient
than his resistive load circuit too.
---
You're either a liar or you have a short attention span or, more likely,
both.

You didn't "help" until you got beat into it.

Here's your "helpful" first response to his original first post:


"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)"


JF
 
Anthony Fremont wrote:

With all due respect, that's more a matter of opinion than one of fact as it
depends upon the specific application. If the ISR is dependant upon the
data that is currently being modified, then disabling INTs for a few
instructions [atomizing the update] is probably the best thing to do to,
unless your ISR can't handle the entry jitter.
Yes, this might be a solution. And you are right, it depends on the
application. But I prefer to write code that can't break, e.g. you use this
nice small code, because you don't use interrupts. Then some years later
someone adds interrupts and forgets to check the rest of the program and it
could cause a bug.

--
Frank Buss, fb@frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de
 
On Mon, 20 Oct 2008 09:28:51 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

On a sunny day (Sun, 19 Oct 2008 19:00:47 -0700) it happened John Larkin
jjlarkin@highNOTlandTHIStechnologyPART.com> wrote in
7hpnf4tmvbjbies94aa7gb8obubrg2se2u@4ax.com>:
Which means that John thinks he has invented something new and
exciting - again. If he spent a little more time learning about what
other people had done, he might waste a little less time boasting
about his latest reinvention of the wheel.


I'll take that for refusal. I suspect nobody is surprised.

John

But I still would like to see your design :)
I suppose I could post a couple. But I was curious if these windbag
poseurs would play the game.

Anybody else want to play with circuits?

John
 
On Mon, 20 Oct 2008 14:03:33 +0100, Eeyore
<rabbitsfriendsandrelations@hotmail.com> wrote:

John Larkin wrote:

Eeyore wrote:
John Larkin wrote:

Not if the "additional" pole is at a much higher frequency than the
previous pole inherent to the capacitances of a heap of fets driven by
some wimpy resistive source. Increasing the bandwidth of the output
stage - the serious speed problem - by, say, 20:1 has got to help the
overall loop.

Just buffering Ciss helps a ton.

Just sticking a unity-gain buffer, like an LT1010, in front of the
gate helps a lot.

I've used discrete Class A, with AB capability to get that node really slewing.


But then, you may as well use an opamp and close the
local loop.

I just have this feeling there's a snag here somewhere. Can't place it yet, ah maybe
slew rate from negative cut-off back to conduction would cause a small dead band (in
time terms).

Graham
There's the catch: you can't let the fet current go to zero, or the
opamp will wind up in the gate-off direction, and recover badly. So
you need a perfect phase splitter, one tht idles both the pullup and
pulldown fets, and whan signal comes along, ramps one up but leaves
the other idling at Iq.

The classic ancient AB amp turns off one side as the other turns on,
but it's soft-off, soft-on so you get away with it.

But fets vary enough in transfer curve, and are nonlinear enough, that
you really need to close a tight loop around each fet if you want to
balance the load and optimize the thermal situation.

John
 
On Oct 11, 11:49 pm, ehsjr <eh...@NOSPAMverizon.net> wrote:
Mark Main wrote:
I have a transformer that is reducing theACsupply voltage down to
25.5VAC, which connects to a thermostat that connects to a Honeywell
water valve for my home boiler system, which then completes the
circuit back to the transformer. I don't see an amperage limit marked
on the transformer--it's about baseball size, so it's not small.

Only 1 of the poles of the relay is used and I would like to use the
other poles of the relay switch to power a red LED (either a standard
LED or a Bi-Polar LED).

This is my home, safety is top of the list (e.g. in my research I've
seen some people offer designs that don't use resistors with theLEDs
or they connect diodes straight across the power supply, both of which
don't seem like they maximize safety).

I want the design to still be safe when one of the parts does
eventually fail.

I need help with the design, and I'd especially like to know the
formulas that were used in the design because I eventually want to
create some LED lighting under my kitchen counter that uses 110VAC...
So if you can help me calculate how I alter the design for 110V vs.
this current 25.5V design that would be great.

I'd like to know how to do this using standardLEDsand also how to
also do it using the bi-polarLEDs.

Thanks for any help... I'm new and learning and have only done a few
basic projects so far.

For the 25V design, you need a 2200 ohm 1/2 watt resistor
in series with the LED and a 1N400x diode in antiparallel
with it. That is explained below.

A simple approach may be best for you.  An LED needs to have
the current limited to a (relatively wide) range, and needs
to be protected against reverse voltage. Placing a diode in
antiparallel with the LED accomplishes the latter. To limit
the current you can use a resistor, and since the range is
relatively wide, precision is not necessary.

To determine the resistance needed to limit current to 10 mA
in a circuit with a 25 volt source, figure 25V/.01A
That equals 2500 ohms.  A close standard value resistor is
2200 ohms. If you use a 2200 ohm resistor that limits
current to no more than 25V/2200ohms which equals 11.36 mA,
which would be fine for an LED.  Such a resistor would need
to dissipate about .284 watts, so you would use a 1/2 watt
resistor.  That is enough figuring in this case for your
needs, but it is not the full  story.

Your current will actually be a little lower than the 11.36 mA,
because the LED drops the voltage roughly 1.5 volts.  So for
completeness, you can re-compute using (Vs-Vf)/R  where Vs is
the source voltage and Vf is the voltage drop of the LED.
Then you get (25-1.5)/2200 or ~10.68 mA

The answer to your second question (about how to design the
circuit for 110 VAC for under cabinet lights):  DON'T.
It won't be safe.

Instead, get a wall wart with a safe low level DC output,
and compute your resistor using the formula used above:
Vs-Vf/I = R where I is current, R is resistance, Vs is
the source voltage and Vf is the voltage drop of the LED.

Ed- Hide quoted text -

- Show quoted text -
Thank you. That gave me the info that I was seeking. I'll be rigging
it up this weekend.
 
On Oct 20, 4:15 am, Jasen Betts <ja...@xnet.co.nz> wrote:
On 2008-10-19, MooseFET <kensm...@rahul.net> wrote:
[...]
We could get "Sharpie" or someone to make up special markers.  The
plastic body of the marker could be some weird combination of colors
that are only used for elections.
With special ink for the finger marks and the marker and special
markers, owning any of them could be made against the law and declared
to be evidence of the intent to commit election fraud.  This would
make things a lot more secure about extra votes being added.

these sorts of laws strike me as inherently bad.

colouring fingers is only needed in societies where the population
does not already have identitiy papers, just check the names of a list
send the lists in for (mechanical) review at the end. investigate any
double-ups.

Here in the US, one of the ways that elections are rigged is to remove
the names of some of the opposing party from the voter lists. Doing
so is a crime but the election is over by time the evidence is usually
discovered. This means that if you succeed, the party that wanted the
result is in charge.

The ones doing it usually seek some sort of cover. There are almost
always cases where the drivers license says perhaps "Adam Baker
Charles" but the voter list says "Adam B. Charles". The ones doing
the purging claim that they are only removing non-existent peoples
names from the list.

In many states of the US criminals lose the right to vote. If the
person in the wrong party happens to have the same name as a known
criminal, bang goes their name.

OTOH if purple fingers are made fashionable it may help voter turn out
:)

what if someone prints 2000 ballot sheets and gets them marked up to
look like real ones. I don't think anyone can sneak 10 extra sheets into the
box while posting their own ballot, so the crook wouls need atleast
200 accomplicies to sneak those fakes past the observers.
The problem is with the observers not the voters. They have the
reason to hang around all day and wait for the guy from the other
party to need to use the restroom. Preventing the custom ink from
being available outside the voting booth will make it a lot hard for
them because they would have to mark the ballots with the special pens
and not something from a drug store.

To prevent ballot boxes from being tampered with or taken away, people
watching would work nicely.

let each candidate nominate some number of observers for each
polling place. (2 or 3 at any one time may be enough)
Often, here in the US, "each" works out to be 2. This makes for too
low of a number. Two would be from the party of the crook. One of
the "good guys" would accept the bribe and one would need to take a
break.

As many as 10 people picked at random like jury duty may be needed.
The ballot boxes could be shipped back
to where they are counted on the transit system's buses.  On election
day, extra buses run while the polls are open to take people to vote.
When the polls close some of those same buses take the boxes to be
counted.  In farming areas, the school buses and the like would be
called into service.

I'm not sure that the volume of paper would justify that.
but it does give 10 observers somwhere to ride, but probably only 2 or
three are needed for that trip.
Buses are pre-existing
They are nearly a stardardized item
The observers never need to take their eyes off the box


I'm not sure how counting is done here, but the ballots are not
transferred long distances and the count is usually concluded by
morning of the next day. there are sometimes one or two electorates
that change hands in the following week when the postal votes are
counted.
Most states of the US have a thing called "ballot measures". These
are issues voted on directly. This makes the ballot a lot longer. I
still think that even if it takes a couple of days, the results are
fast enough.


after counting, the ballots may need to be sent somewhere for archival
but unless the count is contested a high level of security is probably
not needed.
I think that high security should be the rule in all cases. It only
needs to be maintained for less than the time until the next election
so the same vault can serve for each election.

To me, voting by infernal contraption just seems unnatural.
Do you use electronic banking?
 
Bill B wrote:
On Oct 17, 5:55 pm, "Anthony Fremont" <nob...@noplace.net> wrote:
Bill B wrote:
Trying to figure out an easy way to update a single bit within a group
of 24 bits (3 bytes) using a lookup table that returns 8 bits. The
first 5 bits from the table will indicate the bit to be updated (1of
24) and the 6th bit will indicate a set or reset for that particular
bit.

Have any other ideas?
Depends if you have room to trade space for speed.

Assuming that you are using the typical 16Fxx type PIC, you really don't
have any easy way to do it. It might take a little less code if you divide
the 5 bit offset field into two fields. Two bits for the byte number (0,1,
or 2) and three bits for the bit position within the byte. Use the 2-bit
field to set up the FSR to point to the appropriate byte. Then you can just
use the three-bit field to index (by adding to the PCL) into a table that
looks something like this:
retlw 0b00000001
retlw 0b00000010
retlw 0b00000100
retlw 0b00001000
retlw 0b00010000
retlw 0b00100000
retlw 0b01000000
retlw 0b10000000
If necessary, negate the retrieved byte to AND off a bit, or use it as is to
OR one on in the byte pointed to by the FSR.

Yes, that's a good idea, I was using IORWF against say "00010000" to
set bit 4, but I hadn't thought of using the negative "11101111" with
the ANDWF to reset the bit. I'll give that a try.
Another way is to take the bitno in W and shift it left once then have
a computed jump table with 24 following 2 byte entries of the form:

BSF Reg0,0
RETURN
BSF Reg0,1
RETURN
...
BSF Reg0,7
RETURN
BSF Reg1,0 etc.
etc.

RETURN could be GOTO BSDONE

Obviously with long jump tables you have to take care not to have it
spanning a segment boundary or unexpected results will ensue. This is
about the simplest way, indivisible operation for bit change and
possibly the fastest.

Regards,
Martin Brown
 
On Oct 19, 9:25 pm, krw <k...@att.bizzzzzzzzzz> wrote:
In article <6m187dFee7g...@mid.individual.net>,
dirk.bru...@gmail.com says...

krw wrote:
In article <6luv1iFe90m...@mid.individual.net>,
dirk.bru...@gmail.com says...
JeffM wrote:
The official launch is Oct 13, but you can download it now.
http://distribution.openoffice.org/mirrors/#extmirrors

For those of you struggling with folks sending you crap
saved in M$'s new lock-in/lockout file formats, here's the good news:

-- New stuff --
Can open files from M$Office 2007, Office 2008 for OS X
 (.docx, .xlsx, .pptx, etc.)

1024 Columns Per Sheet (was 256)
  -- Excel 2007 will do 16,384 ! (x 1,048,576 !)

Support for (ISO standard) OpenDocument Format 1.2 (ODF)

Runs under OS X without X11

...and OOo has had some VBA support for a while now.

More details:
http://www.openoffice.org/dev_docs/features/3.0/
Just downloaded it.
I cannot understand why anyone would buy MS products when this is free.

Because, unless you are doing trivial work, it isn't compatible with
the other 99.9% who would rather pay for software.

Well, a number of governments think different.

                                               ^ly

So?  The *fact* is that OO is not compatible past the rudiments,
with M$.  It matters not, why or who is (in)compatible with whom.

And the way I heard it, it is MS who has been forced into compatibility
with ODF

Nonsense.  M$ doesn't care about compatibility with M$.
I maintain that they do care. They try to make it so that the new
version can open the files of the old version but the old version
messes up on the files from the new version. This way when one copy
of the new version is brought on site, nearly every copy needs to be
XXgraded to the new version.

At this point I have written a fair amount of code in the OO basic. I
really hope they never decide to change it massively.
 
John Fields wrote:

Eeyore wrote:
John Fields wrote:
Eeyore wrote:

Where would you place the threshold (and what harmonic structure) of audible
THD ?

---
It depends:
http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=GFRC,GFRC:2006-50,GFRC:en&q=harmonic+distortion+threshold+of+audibility

JF

I was interested in YOUR opinion though.

---
No, you weren't.
Yes I absolutely was. Don't tell me what I'm thinking.The absence of a repsonse shows how litle you know about the subject.

Congratulations. I wouldn't employ you.

Graham
 
John Fields wrote:

Eeyore wrote:
John Fields wrote:
Eeyore wrote:
John Fields wrote:
Eeyore wrote:
John Fields wrote:
Eeyore wrote:

You're a babe in arms in this discipline.

---
You wish.

I cut my teeth on audio and was designing and building bridge amplifiers
in the early '60's, even before RCA came out with them, as I recall.

The world has moved on John.

---
As have I, while you guys keep struggling to lower THD to limits which
are so far beyond the threshold of audibility that the point of the
exercise becomes ludicrous.

But it's FUN !

---
So if it's fun for you and your clique it's OK, but if it's fun for
someone else, like Olivier, then you'll do your damnedest to try to make
him feel stupid instead of offering a helping hand?

But I have given him a helping hand by recommending the very best stage for the
job. The complementary emitter follower biased into full Class A. More efficient
than his resistive load circuit too.

---
You're either a liar or you have a short attention span or, more likely,
both.

You didn't "help" until you got beat into it.

Here's your "helpful" first response to his original first post:

"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)"
It's damn practical answer. Like so many posters <sigh> he omitted his real reason
for doing what he wanted. If he'd included that, he'd have got a very different
repsonse.

Graham
 
miso@sushi.com wrote:

Eeyore wrote:
m...@sushi.com wrote:
"Phil Allison" <philalli...@tpg.com.au> wrote:
"Damon Hill"

The vexation I experienced with low-level distortion measurements
with the few designs I could measure with a Tektronix set was that
noise predominated the measurements. I'm not an engineer, and
design for low noise to match distortion levels is beyond me...
as is the price of an AP system.

** It can be very useful to have a digital storage scope when measuring THD
residuals.

Most digital scopes have an "averaging" feature, so as long as you have the
time-base locked to the fundamental, the harmonic residual signal will add
to itself as many times as the scope allows while noise and any AC supply
harmonics tend to disappear from the trace as they are not correlated to the
fundamental sine wave.

Nowadays, many folk like to use a PC with a 24/96 sound card and FFT to do a
spectrum analysis - makes harmonics stand out like dogs balls.

But at such low distortion levels, is it worth it?

** Better ask someone like Halcro ( an Aussie manufacturer).

http://www.halcro.com/home.asp

They have been making a fortune selling $40,000 amps with 0.0005 % THD to
New York's fattest & dopiest Jews.

...... Phil

Or just feed the residual to a DSA. While it is interesting to see
what harmonics are present, looking at the residual relative to the
source is probably more useful. For instance, if the residual error
gets large at the crossover, you know where to tweak. The residual
could also get large at the peaks if the output stage is not beefy, or
some current source is out of compliance on large swings.

The crossover area is the critical one and indeed as you say is also the harmonic
element. If it gets nasty near full power, get a bigger amp !

Graham

For a single sine wave test, the amp getting mushy at the top and
bottom doesn't contribute to the THD as badly as the crossover since
the sinewave itself is flattening out at the top and bottom of the
wave. However, I assume though never examined two tone tests, where
the higher frequency sine wave might distort when riding along the
lower frequency near the crests.
You shouldn't be pushing the amp that hard ideally. IMD will really show up sloppy slew
rates though.

Graham
 

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