chip swelling up and getting fried

[CWatters]

"chris" <nadsinoz@hotmail.com> wrote in message
news:b8996f29.0409081924.412d3c05@posting.google.com...

I have a laptop that needs a power brick at 11V 4.5A that I cannot get
hold of.

In desparation, I tried a different power brick at 15V 3.0A. All
'seems' to work ok. Can I continue using this power brick or am I
causing long term damage?

Is the original brick just a straight constant voltage type or does it have
the current limiting circuit built in for charging the battery?

Which laptop?

 

[petrus bitbyter]

"Matthew" <google@cleantalk.co.uk> schreef in bericht
news:1426aa98.0409080838.5d41cc6a@posting.google.com...

I am building a video circuit to use with a z80-based project.

I am looking to use a 6845 to give a screen resolution of 512*256 with
8 colours.
I have a problem understanding the addressing of the 6845 - it seems
to be only for use with character based video.
I want to use one byte of screen memory to give me 2 pixels (I will
have 2 bits left over for other uses - flashing etc). This means I
have to address 64k memory and have 16 address lines. I also want that
memory to be able to be accessed contiguously from 0 to 64k.

Can someone explain how this could be done?

Many thanks,

Matthew

Matthew,

The 6845 *is* a character based CRT controller but a very versatile one. You
can define the dimensions of a character and you can go graphical by
defining a hight of one pixel.Can't remember whether the width also could by
set to one pixel but the smaller the better. You need one address in the
video memory (RAM) for every character on the screen. Translation to video
is done during the scanning by a character generator, usually a bunch of
(EP)ROM. No need to say you absolutely need a datasheet of the 6845.

petrus bitbyter


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.754 / Virus Database: 504 - Release Date: 6-9-2004

 

[Jean-Yves]

In article <_T10d.73293$C7.44478@amsnews05.chello.com>,
"petrus bitbyter" <p.kralt@reducespamforchello.nl> wrote:

No need to say you absolutely need a datasheet of the 6845

there is one here :
http://www.funet.fi/pub/cbm/documents/chipdata/68b45.zip

--
Jean-Yves.

 

[Chris]

In message <1426aa98.0409090231.1caaa11e@posting.google.com>, Matthew
<google@cleantalk.co.uk> writes

"R. Steve Walz" <rstevew@armory.com> wrote in message
news:<413FA501.6C35@armory.com>...
Why don't you just buy an old MGP or Hercules card? That's exactly
what it is!


Because I want to make it myself.

http://andercheran.aiind.upv.es/~amstrad/docs/hd6845s/hd6845sp.htm

http://andercheran.aiind.upv.es/~amstrad/docs/mc6845/mc6845.htm

http://andercheran.aiind.upv.es/~amstrad/docs/um6845r/um6845r.htm

http://andercheran.aiind.upv.es/~amstrad/docs/crtcnew.html

Hope these are of use!
--
Chris

 

[R. Steve Walz]

Benny wrote:

Objective: The purpose of the Electronic Design Contest is to promote
[]
Award: The 1st winner will be grant $100, and the 2nd winner will be
grant 10% discount coupon.
----------------------

Why don't we just have an award competition, whichever of you spamming
clowns send us a bigger monetary award wins a 17" TV??

-Steve
--
-Steve Walz rstevew@armory.com ftp://ftp.armory.com/pub/user/rstevew
Electronics Site!! 1000's of Files and Dirs!! With Schematics Galore!!
http://www.armory.com/~rstevew or http://www.armory.com/~rstevew/Public

 

[Dave Garnett]

It works up to a point. You need ~ 350C to melt the covering quickly, but if
you apply 350C to the leads of many SM parts, damage will result ! If you
scratch the covering a bit, then a soldering iron at ~260C will enable you
to tin wires and make joints - but it takes much longer.

The other key point about this and similar techniques (wire-wrap for
instance) is that you really need a ground plane for most of todays fast
digital logic. You can buy proto boards with a collander ground plane, and
these work well. Any significant wire length in a ground or power decoupling
circuit is asking for Trouble.

Finally, it is pretty fiddly to do, particularly when you need multiple
connections to each pin. With my aging vision I always need to check my work
under a low power microscope !
D

"Ozone Hole near South Pole" <ozonehole2k@yahoo.com> wrote in message
news:cd22f127.0409141906.1fd6ce10@posting.google.com...

I have just come across this page that describes the progressive
wiring technique.
http://elm-chan.org/docs/wire/wiring_e.html

The author managed to build an MP3 player using a normal prototype
board, with mostly SMT parts, some ICs are as complex as 48 LQFP. The
trick is to connect the parts with thin enamel wire one by one. It
seems to be a very attractive option as I don't have room in my flat
to setup a PCB tank and want to avoid spending money to make the PCBs
professionally.

The technique seems to be very good, but, it does not seem to be a
common technique when I search the web. I wonder if anyone has
experience with this. Also, the polyimide (Kapton) tape mentioned in
the article is hard to locate in my town. Any alternative solution for
that?

Posted Via Nuthinbutnews.Com Premium Usenet Newsgroup Services
----------------------------------------------------------
** SPEED ** RETENTION ** COMPLETION ** ANONYMITY **
----------------------------------------------------------
http://www.nuthinbutnews.com

 

[CWatters]

"Benny" <bennyinomaha2000@yahoo.com> wrote in message
news:62b61c32.0409141512.5253063b@posting.google.com...

Problem: Design DC. motor speed control circuit that is used to
control the speed of direct current.

"speed of direct current" ?

 

[Peter Bennett]

On 16 Sep 2004 02:23:12 -0700, mshams_433@yahoo.com (M.S. Khorrami)
wrote:

Hello everyone
I Have Panasonic TV MODEL TC-14L3T but main transformator fail, did
anyone get information about this,

Transformator Number : 34K406A

You will probably only be able to get that transformer from Panasonic
- power transformers in most commercial products are custom items.




--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca

 

[Peter Bennett]

On 17 Sep 2004 10:54:52 -0700, mshams_433@yahoo.com (M.S. Khorrami)
wrote:

Thanks Peter,
How can i get technical information for this part?

--Khorrami

You probably can't get any more information than may be available in
the service manual for that TV.

Peter Bennett <peterbb@somewhere.invalid> wrote in message news:<8agkk0tedshg15ah3s1lm3v5i26s31l3d0@news.supernews.com>...
On 16 Sep 2004 02:23:12 -0700, mshams_433@yahoo.com (M.S. Khorrami)
wrote:

Hello everyone
I Have Panasonic TV MODEL TC-14L3T but main transformator fail, did
anyone get information about this,

Transformator Number : 34K406A

--
Peter Bennett VE7CEI
email: peterbb4 (at) interchange.ubc.ca
GPS and NMEA info and programs: http://vancouver-webpages.com/peter/index.html
Newsgroup new user info: http://vancouver-webpages.com/nnq

 

[Peter Bennett]

On 18 Sep 2004 01:41:59 -0700, mshams_433@yahoo.com (M.S. Khorrami)
wrote:

There isn't any service manual for my TV, Can you introduce commercial
company to me for this part and help more,
THX,

I suggest you ask again in the news:sci.electronics.repair newsgroup,
if you can't get any help from Panasonic.

--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca

 

[Watson A.Name - \"Watt Su]

"Andre" <testing_h@yahoo.com> wrote in message
news:2c2cf14c.0408231107.6af6ea29@posting.google.com...

"exxos" <exxos@home.com> wrote in message
news:<4127b196$0$20251$cc9e4d1f@news-text.dial.pipex.com>...
"Clint Sharp" <clint@clintsmc.demon.co.uk> wrote in message
newsB0NE1ALTyJBFwyr@clintsmc.demon.co.uk...
In message <41267991$0$20249$cc9e4d1f@news-text.dial.pipex.com>,
exxos
exxos@home.com> writes
Big fat washers come to mind, ive got a few of um now, very large
and
strong, im sure they will come in handy which I need a big fat
washer for
something someday..........
Some of the platters are glass though. IIRC IBM have some glass
platter
drives.

Chris

--
Clint Sharp

Not seen any of those, only the metal types.


Took apart a Gatwicked (i.e. bounced around in luggage handling) hard
disk, 500MB. That had glass platters

The newer miniature laptop disks use them because they provide much
more stable surfaces for the sputter coating of media onto.

-A

I took apart a 2.5 inch HD to see what was inside, and I left the single
platter on the desk, thinking it was metal. I set something heavy on it
and heard a crunch, and yep, it turned out to be a glass platter, broken
into a bunch of splinters. :-(

> > Chris

 

[CBarn24050]

dear reader,

For this moment I am implementing designs in CPLD's(xlinx
xc95-series). I was wondering what is the main difference between a
CPLD and a FPGA?

thanks for your support!

Try reading the data sheets

 

[CWatters]

"Steve Grubb" <steve@sgpr.net> wrote in message
news:5edb58d2.0409200517.64bd7563@posting.google.com...

Hi, I'm looking for something with AC male on one end, and AC female
on the other, that can plug an AC device (sump pump) into, that will
emit an audible tone when the device is running and consuming current.
Kind of like an audible pilot light, or an electric meter that
sings.. I want this so I can be aware upstairs when the sump pump runs
in the cellar, since occasionally it sticks on. This would also alert
us to a plumbing problem. It's a dirt cellar.

Perhaps you could just wire a mains lamp or a mains powered radio across the
pump motor (tune radio to 24 hour station!)

 

[CWatters]

<alondra101@hotmail.com> wrote in message
news:fba2eda0.0409200708.57ef7a91@posting.google.com...

Our "students" AKA taggers like to use some kind of frosting pencil to
graffiti up the mirrors. I'd like to find a way to polish the glass
so that this frosting becomes shiny glass again. I've thought about
rouge. But would something like a clear acrylic or similar make it
shiny? Thanks.

If they really have scratched the glass then it's a lot of work to fix. You
have to polish the whole surface down to the bottom of the deepest scratch
and then repeat with finer and finer compound.

Perhaps their marks are some kind of paint? Try using a scalpel to scrape a
section in a corner somewhere. If you can chip a littos of the frosting off
then it's on the surface of the glass and not cut into it. In which case you
need to find a suitable solvent for the stuff. You may have to try several
different things. Paint stripper may work - it's unlikely to effect the good
parts of the glass but make sure it doesn't drip onto other surfaces as it's
nasty stuff.

 

[ThePetPage]

Hi, I'm looking for something with AC male on one end, and AC female
on the other, that can plug an AC device (sump pump) into, that will
emit an audible tone when the device is running and consuming current.

What you are describing is called a "current transformer". It uses a toroid
coil with only one of the ac mains wire going thru it to detect current flow.
The toroid has maybe 30-40 turns of wire wrapped around it which acts like a
"one-turn transformer". That is fed to an op-amp, then a rectifier and filter,
then could feed a sonalert.

But I agree with the person that replied before me. If you don't actually
require that you sense that CURRENT is flowing, (in other words, the pump is
turning), you could just wire a parallel connection so that when the pump has
power, so does a radio or a buzzer (with a transformer), etc.

 

[Watson A.Name - \"Watt Su]

"CWatters" <colin.watters@pandoraBOX.be> wrote in message
news:csF3d.252283$ZK6.13047834@phobos.telenet-ops.be...

alondra101@hotmail.com> wrote in message
news:fba2eda0.0409200708.57ef7a91@posting.google.com...
Our "students" AKA taggers like to use some kind of frosting pencil
to
graffiti up the mirrors. I'd like to find a way to polish the glass
so that this frosting becomes shiny glass again. I've thought about
rouge. But would something like a clear acrylic or similar make it
shiny? Thanks.

If they really have scratched the glass then it's a lot of work to
fix. You
have to polish the whole surface down to the bottom of the deepest
scratch
and then repeat with finer and finer compound.

No, I'm not talking about scrratches. They're nowhere near as visible
as the frosting pens.

Perhaps their marks are some kind of paint? Try using a scalpel to
scrape a

No, it's some kind of etching pencil, so after awhile the glass becomes
frosted.

section in a corner somewhere. If you can chip a littos of the
frosting off
then it's on the surface of the glass and not cut into it. In which
case you
need to find a suitable solvent for the stuff. You may have to try
several
different things. Paint stripper may work - it's unlikely to effect
the good
parts of the glass but make sure it doesn't drip onto other surfaces
as it's
nasty stuff.

We have spray cans of graffiti remover, which is just such a stuff. It
removes paint no problem. But this isn't paint.

 

[Watson A.Name - \"Watt Su]

"Richard" <spudnuty@lycos.com> wrote in message
news:a686c665.0409202036.33560dc9@posting.google.com...

"CWatters" <colin.watters@pandoraBOX.be> wrote in message
news:<csF3d.252283$ZK6.13047834@phobos.telenet-ops.be>...
alondra101@hotmail.com> wrote in message
news:fba2eda0.0409200708.57ef7a91@posting.google.com...
Our "students" AKA taggers like to use some kind of frosting
pencil to
graffiti up the mirrors. I'd like to find a way to polish the
glass
so that this frosting becomes shiny glass again. I've thought
about
rouge. But would something like a clear acrylic or similar make
it
shiny? Thanks.

If they really have scratched the glass then it's a lot of work to
fix. You
have to polish the whole surface down to the bottom of the deepest
scratch
and then repeat with finer and finer compound.

These pens contain hydrofluoric acid:
"Vandals are increasingly using acid etching pens to damage store
windows. Often an auto glass repair shop can buff out the etching, but
you'll be left with distortion. If you find that your glass has been
etched, DO NOT TOUCH as the acid could burn you. Rinse the area with
lots of water to stop the acid working. Then you will need to decide
whether to replace the glass or have it buffed."
that was from:

http://cityofseattle.net/economicdevelopment/biz_district_guide/biz_dist

_pages/graffiti.htm

and this site about hydrofluoric acid exposure:

http://www.emedicine.com/emerg/topic804.htm

So if it's not too deep you could polish it out like polishing a
telescope mirror with finer grades of rouge. Extreme exposure to
hydrofluoric acid can actually cut grooves in the glass!

You could overcoat with polycarbonate but then they'd probably go back
to emery paper.

Thanks for the good info. I figured rouge would do something, but I
didn't think it would take that much work to buff it out. Maybe it
would just be better to use more etching pencil and make cute Xmasy
patterns all over the mirror, like holly leaves, etc. :0)


> Richard

 

[Watson A.Name - \"Watt Su]

"Steve Grubb" <steve@sgpr.net> wrote in message
news:5edb58d2.0409200517.64bd7563@posting.google.com...

Hi, I'm looking for something with AC male on one end, and AC female
on the other, that can plug an AC device (sump pump) into, that will
emit an audible tone when the device is running and consuming current.
Kind of like an audible pilot light, or an electric meter that
sings.. I want this so I can be aware upstairs when the sump pump runs
in the cellar, since occasionally it sticks on. This would also alert
us to a plumbing problem. It's a dirt cellar.

It seems like would be a simple device, but I don't know what it would
be called.

Thanks for any ideas. -Steve

I would use a big, heavy full-wave bridge rectifier, something rated
for more amps than the sump pump will draw. I've seen 25A bridge
rectifiers available for several dollar each. Or I might try a bridge
rectifier out of an old scrapped AT power supply if it's rated at 6A or
more. Depends on the pump.

Then I'd get a pigtail with a plug on it and a socket and insert the
bridge's two "~" AC leads in series with the hot AC wire between the
plug and socket.

Then I'd put a 1 ohm, ten watt resistor across the bridge's + and -
leads. With the pump plugged into it, I'd measure the voltage drop
across the resistor. Be Careful around AC, it can be deadly! The idea
here is to get the voltage drop across the resistor to be enough to make
a buzzer sound. It might take only a 1 ohm resistor if the pump draws a
few amps, giving a few volts drop across the resistor. Or if the pump
is lower current, then it might take 2 or 5 ohms. But the resistor has
to be a power resistor to handle the current. With a 1 ohm resistor, 3
volts drop times 3 amps gives 9 watts of dissipation, so the resistor
will get hot. Of course, a piezo buzzer goes across the resistor, in
the proper polarity.

Make sure everything is well insulated, since the components have the AC
line voltage on them. I would put all of it inside a metal electrical
outlet box, wide enough for both an outlet and a switch. Instead of the
switch, leave the hole for the switch handle empty and mount the buzzer
so that it's below and the sound can come out the hole.

Remember all this has to reliable enough to never prevent the pump from
working. It could be messy if it doesn't do its job.

 

[Watson A.Name - \"Watt Su]

"CWatters" <colin.watters@pandoraBOX.be> wrote in message
news:lqC3d.252087$Jo5.13009952@phobos.telenet-ops.be...

"Steve Grubb" <steve@sgpr.net> wrote in message
news:5edb58d2.0409200517.64bd7563@posting.google.com...
Hi, I'm looking for something with AC male on one end, and AC female
on the other, that can plug an AC device (sump pump) into, that
will
emit an audible tone when the device is running and consuming
current.
Kind of like an audible pilot light, or an electric meter that
sings.. I want this so I can be aware upstairs when the sump pump
runs
in the cellar, since occasionally it sticks on. This would also
alert
us to a plumbing problem. It's a dirt cellar.

Perhaps you could just wire a mains lamp or a mains powered radio
across the
pump motor (tune radio to 24 hour station!)

Problem is that the AC line going to the motor is usually hot all the
time. The soundmaker would have to be wired _after_ the float switch,
which in the sump pumps I've seen, isn't easily accessible because it
has to be insulated from the water.

 

[CWatters]

Try posting this up...

http://www.healthandsafetycentre.org/i/posters/1996/ha9603.html

or perhaps..

http://www.interclean.com/InterClean/List/hf-warning/Hydrofluoric%20Acid%20report.htm

Quote:" None of the employees were told that contact on two percent of the
body can be fatal"

Perhaps a few random bag searches wearing rubber gloves and breathing kit
would do it?

Who sells this stuff to kids?