Driver to drive?

[Tim Wescott]

Guy Macon wrote:

Kim wrote:

I require a circuit that will:
-display in 5 second increments, every time a switch is closed, on a basic 1
line lcd display (it wont actually be a 5 second increment in reality, this
is count, not a time, but the count has to be in 5 second increments)
-add up these 5 second increments, until they "rollover" into minutes, hours
days months, years.

--snip--

If someone points you to a Basic Stamp by Parallax, don't listen.
You need the real-time clock and crystal timebase of the BasicX,
and the Basic Stamp uses a ceramic resonator that isn't accurate
enough for your purpose.

If you really want someone to do this for you, I can squeeze you in
(see http://www.guymacon.com), but I really think that you can do
this yourself.

The OP would have to clarify, but it appears he wants each external

pulse to be given a value of 5 seconds and counted -- if so then no
real-time clock is necessary.

This would certainly be something that affects processor choice!

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

 

[Fred Bloggs]

Terry Given wrote:

I read a fascinating paper a few years back on electronic one-shots -
literally! They were electronically fired single-shot guns. I forget
exactly how the circuit worked, but basically they turned a switch on
and dumped all of the energy from a cap into a short section of pcb
track sitting below a projectile. All the energy dumps into the track,
and gets converted into heat and projectile motion. They used a 1N4007
in series with a FET as the switch. IIRC the fet leakage current was
controlled/chosen to hold the 1N4007 on the cusp of avalanche breakdown,
but keep dissipation low. To fire the device, the FET was turned hard
on, and the 1N4007 broke down. The large amount of energy involved
created a ball of plasma which swept thru the diode, turning it into a
very effective short. I must dig that back out.....

Nothing new- the electronically fired catridge-less projectile has been
around forever- but usually to achieve extraordinarily high rates of
fire like millions of rounds per minute.
http://www.cnn.com/2003/BUSINESS/06/26/australia.metalstorm/

 

[Pig Bladder]

On Wed, 17 Nov 2004 10:57:19 +0000, Dirk Bruere at Neopax wrote:

Rich The Philosophizer wrote:

On Tue, 16 Nov 2004 18:54:07 +0000, Dirk Bruere at Neopax wrote:


John Larkin wrote:


On Tue, 16 Nov 2004 18:16:19 +0000, Dirk Bruere at Neopax
dirk@neopax.com> wrote:



John Larkin wrote:
On Tue, 16 Nov 2004 17:25:47 +0000, Dirk Bruere at Neopax


dirk@neopax.com> wrote:




John Larkin wrote:




On Tue, 16 Nov 2004 15:55:07 +0000, Dirk Bruere at Neopax
dirk@neopax.com> wrote:






'Rights' have historically been wrested from the powerful by force. See Magna
Carta for a good example. Or maybe the US Constitution.
Our societies are balance of forces.


But the US constitution presumes axiomatic, God-given "inalienable
rights" and defines them in the Bill of Rights. They are assumed to be
absolute.

The Constitution only exists because control was wrested from the British by
force of arms.


Cool. Then why would a bunch of european wimps complain because the US
has a huge military and pretty much does what it wants?

Because your poodle Blair is making us a target along with you?



Too bad; that's what happens to weak people who have no rights.

And how could you get Bush to pull the troops out of Iraq?
Ask him nicely?
Or wait a few years.


I'm just waiting for Little Fallujah Horn.

Fallujah is about one third of a 'Hue'.
Iraq seems to be running along at about one third of a 'Vietnam' overall.
But it's early days.

Does this have anything to do with Kurds?

Kurds and Hue, get it?

--
The Pig Bladder From Uranus, still waiting for some hot babe to ask
me what my favorite planet is.

 

[Joel Kolstad]

"Winfield Hill" <hill_a@t_rowland-dotties-harvard-dot.s-edu> wrote in
message news:cnfd9l02bp9@drn.newsguy.com...

I should add that most of the HV meter probes one finds around a typical
workbench are *not* suitable for pulse measurements. I'm referring to
the DC probes with the 6" proboscis tip and a double banana plug on the
other end of the cable, for use with a multimeter. These employ a long
high-voltage resistor and do not have proper internal shielding, so they
will give you an erroneous (e.g., too high) result for short pulses.

....due to capacitive coupling 'around' the resistor? Or is there some other
mechanism at work?

 

[deaks]

chrisgibbogibson@aol.com (ChrisGibboGibson) wrote in message news:<20041116201005.21510.00000694@mb-m11.aol.com>...

No. Not safely. That's why the spec exists in the first place. You pillock.

Gibbo

Wouldnt it be true to say that the piezo's internal resistance is high
and the voltage would drop considerably when presented with a low ohms
circuit such as the one presented.
deaks

 

[Rich Grise]

On Wed, 17 Nov 2004 01:10:05 +0000, ChrisGibboGibson wrote:

No. Not safely. That's why the spec exists in the first place. You pillock.

This is misleading and rude.

You _can_ safely exceed the breakdown voltage of a junction, IF
you ensure that the power dissipated in the device is less than
some given specified value, which you can find in the data sheet.

If you don't believe this, then please go look up "zener diode"
and "reverse breakdown" in any reasonably qualified electronics
reference.

Thanks!
Rich

 

[Rich Grise]

On Wed, 17 Nov 2004 10:58:29 -0800, Joel Kolstad wrote:

"Winfield Hill" <hill_a@t_rowland-dotties-harvard-dot.s-edu> wrote in
message news:cnfd9l02bp9@drn.newsguy.com...
I should add that most of the HV meter probes one finds around a typical
workbench are *not* suitable for pulse measurements. I'm referring to
the DC probes with the 6" proboscis tip and a double banana plug on the
other end of the cable, for use with a multimeter. These employ a long
high-voltage resistor and do not have proper internal shielding, so they
will give you an erroneous (e.g., too high) result for short pulses.

...due to capacitive coupling 'around' the resistor? Or is there some other
mechanism at work?

As well as 'through' the resistor, yes. Or maybe 'in' it. Win will
know. ;-)

Cheers!
Rich

 

[ChrisGibboGibson]

Rich Grise wrote:

On Wed, 17 Nov 2004 01:10:05 +0000, ChrisGibboGibson wrote:

No. Not safely. That's why the spec exists in the first place. You pillock.


This is misleading and rude.

No it isn't.

You _can_ safely exceed the breakdown voltage of a junction, IF
you ensure that the power dissipated in the device is less than
some given specified value, which you can find in the data sheet.

If you measure the voltage across the diode you will find it hasn't actually
exceeded the breakdown voltage.

If you don't believe this, then please go look up "zener diode"
and "reverse breakdown" in any reasonably qualified electronics
reference.

I think perhaps you'd better do that.

Put 20 volts across a 10 volt zener, not via a resitor. I want you to "measure*
20 volts across the zener. See what happens. This is rather basic.

Gibbo

 

[Rich The Philosophizer]

On Wed, 17 Nov 2004 10:36:43 -0800, John Larkin wrote:

On Wed, 17 Nov 2004 03:55:16 GMT, Rich The Philosophizer
....
I'm just waiting for Little Fallujah Horn.


Would you enjoy that? Civil war, chaos, a corrupt Taliban-like islamic
tyranny, women forbidden from education and being beaten in the street
for uncovering a wisp of hair? Would you enjoy seeing terror
destabilize a civilization so the the US can be humbled?

Would you enjoy that?

You got all this from "Little Fallujah Horn"?

What planet are you from again?

Ever heard of "Little Big Horn"? The way I understand it, Gen'l
Custer led a platoon or so of soldiers on what he thought was
going to be a raid, and they thought the battle was a walk,
until three hundred thousand eleventy jillion gazillion Indians
popped out of the woodwork and slaughtered them to a man.

That would be unfortunate for the soldiers, but they _did_ sign
up knowing that there are certain risks attendant to going into
battle.

It would not be fun to watch, but it would give me another
chance to say "I told you so!" <sticks out tongue>

Other than that, thanks for another glimpse into the workings of
what's apparently a very troubled mind.

Good Luck,
Rich

 

[Reg Edwards]

On the suggestion of Ian White, G3SEK, program SELFRES2 has been modified by
the addition of an extra operating facility.

The terminating impedance at the other end of the line from the coaxial
choke, which was fixed at 20 ohms, can now be varied between 1ohm and 1000
ohms from the keyboard.

The name has been changed to SELFRES3 and is now available from website
below. If you have already downloaded the earlier version which is no longer
available, overwrite it with SELFRES3.
----
...........................................................
Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
............................................................

 

[Nicholas O. Lindan]

"legg" <legg@nospam.magma.ca> wrote

can set the
others off in a chain.

Not only can, but does. Always. Found out the hard way ...

The reverse voltage across a string of diodes will not be equally divided.
One diode will accumulate the majority of the drop, go into avalanche -
creating a short and increasing the voltage across the remaining diodes,
then the next diode will do the same, and the next ... till you have a dead
short across the string and something goes poof.

High value resistors, so that Ires >> Ileakage, in series with each
diode will equalize the voltage along the diode string. Be sure
not to exceed the voltage rating on the resistors; resistors can
be safely strung for high voltage.

--
Nicholas O. Lindan, Cleveland, Ohio
Consulting Engineer: Electronics; Informatics; Photonics.
Remove spaces etc. to reply: n o lindan at net com dot com

 

[Rich Grise]

On Wed, 17 Nov 2004 22:42:01 +0000, ChrisGibboGibson wrote:

Rich Grise wrote:

On Wed, 17 Nov 2004 01:10:05 +0000, ChrisGibboGibson wrote:

No. Not safely. That's why the spec exists in the first place. You pillock.


This is misleading and rude.


No it isn't.

You _can_ safely exceed the breakdown voltage of a junction, IF
you ensure that the power dissipated in the device is less than
some given specified value, which you can find in the data sheet.


If you measure the voltage across the diode you will find it hasn't actually
exceeded the breakdown voltage.

If you don't believe this, then please go look up "zener diode"
and "reverse breakdown" in any reasonably qualified electronics
reference.


I think perhaps you'd better do that.

Put 20 volts across a 10 volt zener, not via a resitor. I want you to "measure*
20 volts across the zener. See what happens. This is rather basic.

Oh - I see your point - you can't get a voltage _over_ the breakdown
voltage, because that's where the zener knee is.

OK, fair enough. But just doing that doesn't automatically destroy
the diode, as long as you limit the current and are happy with
the resulting (possibly poorly) regulated voltage.

So I was wrong, but only to the extent that I misunderstood
what you were trying to say.

But it was still rude to call the guy names. >:-[

Thanks,
Rich

 

[Rich Grise]

On Thu, 18 Nov 2004 01:22:52 +0000, Nicholas O. Lindan wrote:

"legg" <legg@nospam.magma.ca> wrote

In a series string, the break-back of one series [diode] can set the
others off in a chain.

Not only can, but does. Always. Found out the hard way ...

The reverse voltage across a string of diodes will not be equally divided.
One diode will accumulate the majority of the drop, go into avalanche -
creating a short and increasing the voltage across the remaining diodes,
then the next diode will do the same, and the next ... till you have a dead
short across the string and something goes poof.

High value resistors, so that Ires >> Ileakage, in series with each
diode will equalize the voltage along the diode string. Be sure
not to exceed the voltage rating on the resistors; resistors can
be safely strung for high voltage.

I've even seen it done with capacitors. This can be useful for a
HV, low-current supply, like a focus electrode.

Cheers!
Rich

 

[Pooh Bear]

Rich Grise wrote:

On Wed, 17 Nov 2004 22:42:01 +0000, ChrisGibboGibson wrote:

Rich Grise wrote:

On Wed, 17 Nov 2004 01:10:05 +0000, ChrisGibboGibson wrote:

No. Not safely. That's why the spec exists in the first place. You pillock.


This is misleading and rude.


No it isn't.

You _can_ safely exceed the breakdown voltage of a junction, IF
you ensure that the power dissipated in the device is less than
some given specified value, which you can find in the data sheet.


If you measure the voltage across the diode you will find it hasn't actually
exceeded the breakdown voltage.

If you don't believe this, then please go look up "zener diode"
and "reverse breakdown" in any reasonably qualified electronics
reference.


I think perhaps you'd better do that.

Put 20 volts across a 10 volt zener, not via a resitor. I want you to "measure*
20 volts across the zener. See what happens. This is rather basic.


Oh - I see your point - you can't get a voltage _over_ the breakdown
voltage, because that's where the zener knee is.

OK, fair enough. But just doing that doesn't automatically destroy
the diode, as long as you limit the current and are happy with
the resulting (possibly poorly) regulated voltage.

So I was wrong, but only to the extent that I misunderstood
what you were trying to say.

But it was still rude to call the guy names. >:-[

Oh c'mon !

He basically asked if it's OK to ignore the datasheet.


Graham

 

[Mhound]

You will have to give a lot more information...
What hard drive do you have
What operating system
What happened ? accidental erasure ?
Hard Drive failure ?
How much data.
Any thing else you can think of
Do not copy anything on to this drive, or you will overwrite information !

M


"CK@@L" <kanglck1@singnet.com.sg> wrote in message
news:cngvp0$eva$1@reader01.singnet.com.sg...

Hi, I was asked to referred to this newsgroup for some expert advise, can
anyone help pls!

"CK@@L" wrote in message :-

I have accidentally wipe out my years of data in my HDD & now is zero

files. Can anyone advise how to retrieve the lost data & can recommend

where to go to restore the data. Thanks.

 

[Chaos Master]

In article <cngvp0$eva$1@reader01.singnet.com.sg>,
kanglck1@singnet.com.sg says...

Hi, I was asked to referred to this newsgroup for some expert advise, can
anyone help pls!

There's professional software used for hard drive data recovery, and
companies that do this service.

If the HD is FAT16 (not likely) even UNDELETE from DOS 6.22 may be
enough.

But, _don't use_ the HD that has data which you want to be recovered.

[]s
--
Chaos MasterŽ, posting from somewhere near Porto Alegre, Brazil.
"It's not what it seems, not what you think. No, I must be dreaming."

http://marreka.no-ip.com | http://tinyurl.com/46vru
http://renan182.no-ip.org | http://marreka.blogspot.com (in Portuguese)

 

[Rich Grise]

On Thu, 18 Nov 2004 10:40:46 +0800, CK@@L wrote:

Hi, I was asked to referred to this newsgroup for some expert advise, can
anyone help pls!

"CK@@L" wrote in message :-

I have accidentally wipe out my years of data in my HDD & now is zero

files. Can anyone advise how to retrieve the lost data & can recommend

where to go to restore the data. Thanks.

If it were me, I'd start with the yellow pages. It needs to be
somebody local, because you _will_ have to take the drive to them.

They have equipment that can read whatever's on the tracks, but
then you have the horrendous job of reassembling all of your data.

But it is doable, so I've heard, as long as it hasn't actually
been overwritten.

Good Luck!
Rich

 

[Rich The Philosophizer]

On Wed, 17 Nov 2004 15:33:12 -0800, John Larkin wrote:

On Wed, 17 Nov 2004 23:34:20 GMT, Rich The Philosophizer
On Wed, 17 Nov 2004 10:36:43 -0800, John Larkin wrote:
On Wed, 17 Nov 2004 03:55:16 GMT, Rich The Philosophizer
...
I'm just waiting for Little Fallujah Horn.

Would you enjoy that? Civil war, chaos, a corrupt Taliban-like islamic
tyranny, women forbidden from education and being beaten in the street
for uncovering a wisp of hair? Would you enjoy seeing terror
destabilize a civilization so the the US can be humbled?

Would you enjoy that?
....
It would not be fun...
^^^^^^^^^^^^^^^^^^^

I'll take that for a "yes."

OK. It's perfectly clear. Whatever it is you're using instead of
a brain sees "no" and translates it to "yes."

I wonder if anybody's recording these things for a case study.

Thanks,
Rich

 

[Rich Grise]

On Wed, 17 Nov 2004 19:38:59 -0800, Winfield Hill wrote:

Rich Grise wrote...
ChrisGibboGibson wrote:
Rich Grise wrote:
ChrisGibboGibson wrote:

No. Not safely. That's why the spec exists in the first place.
You pillock.
This is misleading and rude.

No it isn't.

You _can_ safely exceed the breakdown voltage of a junction, IF
you ensure that the power dissipated in the device is less than
some given specified value, which you can find in the data sheet.

If you measure the voltage across the diode you will find it hasn't
actually exceeded the breakdown voltage.

If you don't believe this, then please go look up "zener diode"
and "reverse breakdown" in any reasonably qualified electronics
reference.

I think perhaps you'd better do that.

Put 20 volts across a 10 volt zener, not via a resitor. I want you
to "measure* 20 volts across the zener. See what happens. This is
rather basic.

Oh - I see your point - you can't get a voltage _over_ the breakdown
voltage, because that's where the zener knee is.

OK, fair enough. But just doing that doesn't automatically destroy
the diode, as long as you limit the current and are happy with
the resulting (possibly poorly) regulated voltage.

So I was wrong, but only to the extent that I misunderstood
what you were trying to say.

But it was still rude to call the guy names. >:-[

Rich, you were correct, and was Chris wrong. You certainly can go
well above the specified breakdown voltage. That's because this is
simply the manufacturer's value, above which at some point you will
encounter real breakdown. And when you do finally have breakdown,
you'll find it's like a stiff zener plus an internal resistance, so
the measured breakdown voltage depends on the current. Furthermore
breakdown voltage increases as the junction heats up (AoE fig 6.20).
Bottom line, the voltage will be above the manufacturer's breakdown
spec. Moreover, no damage will occur if breakdown energy (current
* voltage * time) is low enough to keep junction heating below safe
maximums. As detailed with transient thermal dissipation curves
(i.e. (maximum surge-power) and thermal mass calculations. That's
safe. It's basically what you said. Avalanche can be your friend.
You can that to the bank. :&gt Yep, that's my educated opinion.

I shall now go lower myself into a hot tub full of molten chocolate,
and my life will be complete.

AAAAAaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhhhhhh.....


[for those of you who are just tuning in, I have just been Blessed.
This may very well go down in history as the pinochle of my life
story. Other people climb mountains. I try to say something worthwhile.


So, when does the shoe drop? ;-) ]

Thanks, Win. ;-)
Rich

 

[Paul Burke]

CK@@L wrote:

I have accidentally wipe out my years of data in my HDD & now is zero


files. Can anyone advise how to retrieve the lost data & can recommend


where to go to restore the data. Thanks.

To your backup copies of course. What, no backups? Self inflicted
injury, court martial, dishonourable discharge.

Having said which, I did just that ONCE. I used PC-Tools (in the days of
DOS and 40 meg disks), searched through the disk block by block, and
recovered nearly everything I needed. But it took days of late nights
and heartbreak. In these days of effectively free CDs, backup everything
frequently. Make sure you have all your installation disks safe too.

Paul Burke