sci.electronics.repair - 25 new messages in 10 topics - digest

sci.electronics.repair
http://groups.google.com/group/sci.electronics.repair?hl=en

sci.electronics.repair@googlegroups.com

Today's topics:

==============================================================================
TOPIC: TVs compatible, from one continent to the next??
http://groups.google.com/group/sci.electronics.repair/t/38d677af192b8653?hl=en
==============================================================================

== 1 of 8 ==
Date: Sat, Jan 8 2011 10:19 am
From: "Geoffrey S. Mendelson"

mm wrote:
> For 60 years, USA tv signals and European ones, etc. were not
> compatible.

Sort of. Multisystem TV's Were common in the 1980's. There were only 4 systems
of video, although there there were lots of ways to transmit them.

They were NTSC (60Hz, 3.57mHz color carrier), 50Hz PAL, 60Hz PAL, and 50Hz
SECAM. There also was 405 line UK TV (dropped in the early 1980's) and
NTSC 4.43 (same signal, color carrier moved to make cheaper playback equipment).

I still have a 1985 Sharp TV set that will play both NTSC versions, All PAL
versions, and SECAM from anywhere except France. I had a 14 system VCR that
would play and record French SECAM and a different TV set to play it on.

My kids use a 21 inch 4:3 CRT that is simialr, except that it does not
have a French tuner. It added component and S-video instead.

> Did they make digital tvs compatible from the US to Europe to Asia to
> Australia, etc?

I also have had VCRS that included digital TV standards converters. They
were multisystem VCRs with the conversion feature added on top.

But digital TV was not needed, analog TV's played the signals fine. It was
just a matter of adding the correct hardware.

> I think they should have. If not, is it only the 50 versus 60
> vertical scan rate that was the problem?

The color carrier. NTSC used a phase modulated color carrier at 3.5mHz. PAL
used a similar carrier at 4.43mHz. To fix a problem noticed in NTSC signals
the BBC adopted the practice (which was in the proposed NTSC spec but
dropped to save money) of alternating the phase every other line, hence
the name PAL (Phase Alternating Line).

TV sets which would lock on 50Hz or 60Hz signals as appropriate were not
a technical issue and by 1980 almost all made would anyway.

SECAM used a different decoding method, but those chips were easily found,
and it was common to see TV sets and VCRS that would play/record SECAM signals
broadcast using PAL over the air standards. Eastern Europe (Warsaw Pact
countries), most Arab countires, China, and the USSR used some form of SECAM
encoded signals with PAL frequencies.

The French used a different channel spacing, and AM sound, which made
their SECAM signals impossible to tune with the correct tuner. It also made
Eastern European TVs worthless in France and vice versa.

> I don't think I've read anything about this.

You either must have head your head under a rock, or live in the US and never
traveled out of there.

Note that I had several multisystem TV sets, VCRS (BETA and VHS), and even
a portable combination AM/FM/SW receiver and TV set that looked like a
Star Treck tri-corder, all puchased in the 1980's in Philly.

Geoff.

--
Geoffrey S. Mendelson N3OWJ/4X1GM
Those who cannot remember the past are condemned to misquote it.

== 2 of 8 ==
Date: Sat, Jan 8 2011 10:34 am
From: "Geoffrey S. Mendelson"

Allodoxaphobia wrote:

> Who are these "they"?

Akai, Sony, Toshiba, JVC, NEC, Hitachi, Sharp, Panasonic (National),
Memorex (Radio Shack house brand) are just the TV's and VCR's I've owned.

Geoff.

--
Geoffrey S. Mendelson N3OWJ/4X1GM
Those who cannot remember the past are condemned to misquote it.

== 3 of 8 ==
Date: Sat, Jan 8 2011 3:40 pm
From: Jim Yanik

"Geoffrey S. Mendelson" <gsm@mendelson.com> wrote in
news:slrniihaih.e8v.gsm@cable.mendelson.com:

> mm wrote:
>> For 60 years, USA tv signals and European ones, etc. were not
>> compatible.
>
> Sort of. Multisystem TV's Were common in the 1980's. There were only 4
> systems of video, although there there were lots of ways to transmit
> them.
>
> They were NTSC (60Hz, 3.57mHz color carrier), 50Hz PAL, 60Hz PAL, and
> 50Hz SECAM. There also was 405 line UK TV (dropped in the early
> 1980's) and NTSC 4.43 (same signal, color carrier moved to make
> cheaper playback equipment).
>
> I still have a 1985 Sharp TV set that will play both NTSC versions,
> All PAL versions, and SECAM from anywhere except France. I had a 14
> system VCR that would play and record French SECAM and a different TV
> set to play it on.
>
> My kids use a 21 inch 4:3 CRT that is simialr, except that it does not
> have a French tuner. It added component and S-video instead.
>
>> Did they make digital tvs compatible from the US to Europe to Asia to
>> Australia, etc?
>
> I also have had VCRS that included digital TV standards converters.
> They were multisystem VCRs with the conversion feature added on top.
>
> But digital TV was not needed, analog TV's played the signals fine. It
> was just a matter of adding the correct hardware.
>
>> I think they should have. If not, is it only the 50 versus 60
>> vertical scan rate that was the problem?
>
> The color carrier. NTSC used a phase modulated color carrier at
> 3.5mHz. PAL used a similar carrier at 4.43mHz. To fix a problem
> noticed in NTSC signals the BBC adopted the practice (which was in
> the proposed NTSC spec but dropped to save money) of alternating the
> phase every other line, hence the name PAL (Phase Alternating Line).
>
> TV sets which would lock on 50Hz or 60Hz signals as appropriate were
> not a technical issue and by 1980 almost all made would anyway.
>
> SECAM used a different decoding method, but those chips were easily
> found, and it was common to see TV sets and VCRS that would
> play/record SECAM signals broadcast using PAL over the air standards.
> Eastern Europe (Warsaw Pact countries), most Arab countires, China,
> and the USSR used some form of SECAM encoded signals with PAL
> frequencies.
>
> The French used a different channel spacing, and AM sound, which made
> their SECAM signals impossible to tune with the correct tuner. It also
> made Eastern European TVs worthless in France and vice versa.
>
>> I don't think I've read anything about this.
>
> You either must have head your head under a rock, or live in the US
> and never traveled out of there.
>
> Note that I had several multisystem TV sets, VCRS (BETA and VHS), and
> even a portable combination AM/FM/SW receiver and TV set that looked
> like a Star Treck tri-corder, all puchased in the 1980's in Philly.
>
> Geoff.
>

AFAIK,the TV systems are STILL incompatible;
Europe uses different broadcast modulation schemes and different frequency
assignments.

--
Jim Yanik
jyanik
at
localnet
dot com

== 4 of 8 ==
Date: Sat, Jan 8 2011 3:49 pm
From: "Dave Plowman (News)"

In article <Xns9E67BE4414111jyaniklocalnetcom@216.168.3.44>,
Jim Yanik <jyanik@abuse.gov> wrote:
> AFAIK,the TV systems are STILL incompatible; Europe uses different
> broadcast modulation schemes and different frequency assignments.

The frequencies which suit small densely populated countries close
together might well not suit a large one with large distances between
centres of population.

--
*Starfishes have no brains *

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.

== 5 of 8 ==
Date: Sat, Jan 8 2011 3:59 pm
From: "Phil Allison"

"William Sommerwerck"
>
> Digital TV has its own formats and standards. It is NOT a "digitization"
> of
> NTSC or PAL.

** False argument.

The video signal that is digitised varies in the number of lines and fields
per second.

PAL is synonymous with 50 fields per second.

NTSC is synonymous with 60 fields per second.

"NTSC" badged DVDs when played on most DVD players come out as " PAL 60"
video - where the number of lines is correct but the field rate is 60
Hz..

The TV set in use must be able to cope with this.

.... Phil

== 6 of 8 ==
Date: Sat, Jan 8 2011 6:49 pm
From: "Geoffrey S. Mendelson"

Jim Yanik wrote:
> AFAIK,the TV systems are STILL incompatible;
> Europe uses different broadcast modulation schemes and different frequency
> assignments.

I assume in this case you are talking about digital TV. It all depends upon
how you look at it. I don't know about the pre-war 405 line English system,
which finally was stopped in the 1980s. However the 525 line US system and
and 625 line English/French systems were basicly the same, a "flying spot"
of light, zero volts being white and about one volt being black. The scanning
speed was the same, the US system had less lines because it scanned 60 times
a second, the English/French 50.

A DC syncrchronization aka "sync" pluse was included to keep everything
together so if signal got scrambled, the TV would bring it back together
quickly.

Those rates were chosen because the studio lights were arc lights and flashed
on and off at the power line rate, so the TV cameras had to be syncronized
to them or you would get moving black stripes across the screen.

The RCA system for compatible color TV (compatible with black and white),
used 1/4 of the color information based on the fact that your eye only sees
about that much. The color information was encoded on a phase modulated
3.57mHz subcarrier, which at the time was beyond the picture information, but
still within the transmitted signal.

The original RCA system, alternated the phase of the carrier every line,
so that it would fix itself if there was a transmssion or syncrhonization
problem. To save money, the National Television Standards Commitee (NTSC)
which chose the standard, dropped the alternating phase.

When the BBC adopted their 625 line system to replace the 405, they used a
modification of the original RCA system with a 50 Hz field rate (25Hz frame
rate) which gave them 625 lines. Because there was more modulation, 3.57mHz
was still inside the picture, so they moved the color subcarrier up to 4.43
mHz. As an "in your face" they called the system PAL, Phase Alternating Line,
to differentiate it from the NTSC choice.

The French used a different color encoding system called SECAM, which was also
based on the RCA system (1/4 color, 4.43mHz color carrier) but designed
to be totally incompatible so that you could not watch French TV in England
and vice versa.

NTSC stands for National Television Standrds Comittee, PAL for Phase Alternating
Line, and SECAM is a French acronym for what could be loosely translated as
system of transmitting color TV.

Although the frame rates were different, and the color carriers at different
frequencies, the information was basicly the same, and pretty much encoded
the same way. So it was pretty easy, but expensive to build multisystem
TVs.

Except for the people in the channel Islands, or on the coasts of England
or France, there was no reception of signals anyway, so no one would buy
them anyway.

As the 1960's progressed and TV spread throught the world, variations of
NTSC, PAL and SECAM were adopted either because the standards fit the
former colonial powers that ran the countries or they did not fit the
country next door. So the UK used PAL, the French SECAM, Germany PAL (but
modified so that the tuners would not work with UK signals), East Germany
used SECAM (but modified to use the cheaper west German tuners) and so on.

So there were many ways of encoding the video, but it all came down to a
number between 0 and 1 for brightness and 1/4 color information.

In the early 1980's satellite TV became a problem. Multisystem TV sets
existed, once you put a signal up, there was no way to stop someone from
receiving it if they could see your signal. In the US, the requirment for
a Federal license for a satellite dish was dropped, and in many places there
never was one.

HBO was the leader of the movement to prevent people watching these signals
and pushed for a way of encrypting satellite video. What they did was to
embrace the original MPEG-1 video standard, which was then encrypted using
the US DES (Data Encryption Standard). DES was chosen because it was illegal
to export DES chips from the US, which made it illegal to export HBO
receivers.

The MPEG-1 standard was simply a digital compression based by taking the two
relevant bits of information, brightness and color and combining them and
using various mathematical compression algorythms. In the end though what
went in was very much the same INFORMATION in an analog TV signal because
that's what they had coming in and that's what they wanted coming out.

The MPEG-1 standard included various other things, such as the ability to
have more than one video program, more than one audio channel per program,
and several different digial audio compression choices from none to
what later became MP3 (shortend form of it's full name).

Over the years there have been improvements to the MPEG-1 standard, to become
the MPEG-2 (aka MP2) which is used in DVDs. DVD's for those that don't know
are MPEG-2 video streams represented in flat files, with some extra indexing
information.

In some places there was a short flirtation with encoding MPEG-1 signals
on CDs (video CDs). Commodore made a version of the Amiga called the PC-TV,
using the Philips system and I think there was a competing Sony one.

VCDs took off eventually because video tapes and players and later DVDs
were taxed over 200% in some countries, but computers with CD drives
were not. :-)

There are many compression techniques in use, but the ones used for TV
transmission still work very much the same way, with the light level and color
information being the same as it was in the RCA system.

The data transmitted is still almost universally MPEG transmission streams,
with different compression and encoding methods. Because some countries
still have TV sets that flash at 60 times a second and others at 50, the
frame rates of 25 and 30 have been kept, but are really meaningless. There
really are three rates in use, 24 (film), 25 (used for film and video) and
30 (video). TV set's just play them and whatever decoder box you use or disk
player just converts them to the national standard that is expected of them.

What is loosely called MPEG-4 standards have no frame rate per se, a frame
changes only when the information on the screen changes. So a live action
sporting event may have the full 25 or 30 frames per second, but a photo of
two people watching a sunset in silence may only have 10 or 12.

As for over the air, there are three currently used systems of digital
TV. It's up to the country to decide which standard is used in their country
and I'm sure politics matters. The most common is the DVB-T (digital video
broadcast terrestrial), which has been in use in the EU for a long time now.
It's relatively simple, cheap to produce and unencumbered by expensive
patents.

The US uses a system called ATSC (American Television Standards Committee),
which is different than the DVB-T, although it does basicly the same thing.
Compared to the DVB-T system, which is much older, it uses more sophistocated
chips, with more expensive patent licenses.

DVB-T and ATSC tuners are incompatible. My guess is that was done so that
US manufacturers could get a financial incentive for choosing that system,
in terms of licensing fees, instead of fighting cheap knock-offs from China.

There are companies that manufacture dual DVB-T/ATSC tuner chipsets, they
are targetd to laptops but will eventually find their way into pocket TVs
for travelers.

The third system which I mentioned is Japanese in origin and is incompatble
with the other two. I know nothing about it, except that a few south asian
countries have chosen it.

So if you are still reading, the answer is basicaly that while the INFORMATION
has not changed since the early 1950's, the way of encoding, compressing and
transmitting it has changed, but that does not make it inaccessable.

While you could buy a multisystem analog TV or VCR to cross borders as it were
you can still do so digitally. Since the videos transmitted are basicaly the
same (MPEG transport streams) world wide, it's just a matter of a tuner chip
if you go (signally) from country to country, and if you receive your signals
in another method (over the internet, from a recording, etc), then they are
pretty much the same.

Geoff.

--
Geoffrey S. Mendelson N3OWJ/4X1GM
Those who cannot remember the past are condemned to misquote it.

== 7 of 8 ==
Date: Sat, Jan 8 2011 7:21 pm
From: "Phil Allison"

"Geoffrey S. Mendelson"

> NTSC stands for National Television Standrds Comittee, PAL for Phase
> Alternating
> Line, and SECAM is a French acronym for what could be loosely translated
> as
> system of transmitting color TV.

** Everyone knows that NTSC stands for:

" Never Twice the Same Color"

and SECAM =

" Something Essentially Contrary to the American Method "

.... Phil

== 8 of 8 ==
Date: Sat, Jan 8 2011 7:34 pm
From: "Michael A. Terrell"

Phil Allison wrote:
>
> "Geoffrey S. Mendelson"
>
> > NTSC stands for National Television Standrds Comittee, PAL for Phase
> > Alternating
> > Line, and SECAM is a French acronym for what could be loosely translated
> > as
> > system of transmitting color TV.
>
> ** Everyone knows that NTSC stands for:
>
> " Never Twice the Same Color"

As stupid as always. VITS took care of that over 30 years ago. That
was long before you had your last cohernet thought.

--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

==============================================================================
TOPIC: Ethical question.
http://groups.google.com/group/sci.electronics.repair/t/0951ee48819ee2bb?hl=en
==============================================================================

== 1 of 3 ==
Date: Sat, Jan 8 2011 10:37 am
From: JeffM

Arfa Daily wrote:
>a friend of mine who does computer service[...]
>says that there are download dates and so on,
>
I can't imagine what the "and so on" could possibly be.
Sounds like nonsense to me.

>deeply embedded in the files,
>
"Touch" utilities have been around since the dawn of computing
and can alter the file dates at will.

The repair person having possession of the computer
queers the chain of custody.
If I was on a jury hearing this, I'd consider the whole case suspect.

>he says that in all the years that he's been doing it,
>he has never seen a machine come in for repair, with CP on it.
>
Yet another unethical snooper.

== 2 of 3 ==
Date: Sat, Jan 8 2011 11:24 am
From: "Geoffrey S. Mendelson"

JeffM wrote:
> "Touch" utilities have been around since the dawn of computing
> and can alter the file dates at will.

Anyone who can use a search engine can find a bootable disk image/USB stick
image of disk utilites that let you read all sorts of disks, in all sorts
of condition. They allow you to look at files without setting access flags
and dates, etc.

Someone mentioned using Acronis True Image to image a disk, that leaves
no records and then if you were to make the image onto a permanent medium,
such as a DVD, you can then make a copy of the file off of the image and no
record is made on the image of the access.

> The repair person having possession of the computer
> queers the chain of custody.
> If I was on a jury hearing this, I'd consider the whole case suspect.

What chain of custody? This is not an episode of CSI, my giving you a computer
to fix, and having a recipt for the the computer or a repair is not a chain
of custody. It's evidence that you had it and I did not. Evidence is not
proof and it's certainly not any evidence that once I gave it to you, you kept
control of it.

> Yet another unethical snooper.

That I agree.

Geoff.

--
Geoffrey S. Mendelson N3OWJ/4X1GM
Those who cannot remember the past are condemned to misquote it.

== 3 of 3 ==
Date: Sat, Jan 8 2011 1:10 pm
From: Baron

> On Thu, 06 Jan 2011 11:58:21 -0600, Jeffrey Angus
> <jangus@suddenlink.net> wrote:
>
> I remember several years ago, something similar happened to Pete
> Townshend of "The Who". He brought his computer into a shop for
> service and the tech squealed on him because there was some child
> abuse photos on there.

FWIW. That was the store manager trying to take advantage of free
publicity when it was realised who the owner was !

--
Best Regards:
Baron.

==============================================================================
TOPIC: free useful software and hot actress wallpapers
http://groups.google.com/group/sci.electronics.repair/t/9fa1d1cf56d603fe?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 8 2011 10:50 am
From: varma

http://www.celebsimzs.com
http://www.photovediodating.com

==============================================================================
TOPIC: FS: Samsung Convergence Processor Module
http://groups.google.com/group/sci.electronics.repair/t/b9808d9250676413?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 8 2011 11:23 am
From: "Chris F."

Part # BP95-00151A, replaces several different part numbers on many Samsung
sets. I purchased this new but it turns out I didn't need it after all, so
I'm selling it to try and cut my losses. I paid close to $100 for it but am
only asking $50, plus shipping ($10 anywhere within the USA or Canada).

==============================================================================
TOPIC: MOBILE ANTI VIRUS FREE & SEXY BIKINI GIRLS
http://groups.google.com/group/sci.electronics.repair/t/f4184eb9e9665bf8?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 8 2011 11:38 am
From: anjana

http://www.celebsimzs.com/2011/01/free-antivirus-software.html

http://www.photovediodating.com/bikini-models.html

==============================================================================
TOPIC: remote control keypad conductivity repair
http://groups.google.com/group/sci.electronics.repair/t/8b03ab352dcfc1b2?hl=en
==============================================================================

== 1 of 7 ==
Date: Sat, Jan 8 2011 11:49 am
From: Thomas Williams

For remote controls that have been properly cleaned out and still
don't work like new, I understand some conductive material needs to be
coated onto the circuit board contacts on the inside of the pad
buttons. Reviewing web discussions of this I wonder if a good approach
may be to mix graphite in silicone glue and lightly coat the surface
of the pad's underside. Anyone tried this or have a thought on it?
Others have used electrically conductive paint (e.g., that purchased
at auto supply stores to reconduct broken rear window defrost
circuits) but that would not seem to be as flexible as silicone glue
with conductive material mixed in it. I did read where someone mixed
finely shredded copper (from pipe) with thinly diluted white glue and
it worked well (but for how long?). It would seem that the latter
approach would be better if silicone glue was used, as it is more
flexible. What ye think?

== 2 of 7 ==
Date: Sat, Jan 8 2011 4:52 pm
From: "Phil Allison"

"Thomas Williams"
>
> For remote controls that have been properly cleaned out and still
> don't work like new, I understand some conductive material needs to be
> coated onto the circuit board contacts on the inside of the pad
> buttons. Reviewing web discussions of this I wonder if a good approach
> may be to mix graphite in silicone glue and lightly coat the surface
> of the pad's underside. Anyone tried this or have a thought on it?

** Think the graphite might simply dissolve in the silicone adhesive and the
surface remain non conducting.

Conductive glues are rare animals for this reason.

Why don't YOU try it ??

.... Phil

== 3 of 7 ==
Date: Sat, Jan 8 2011 5:24 pm
From: Jamie

Phil Allison wrote:

> "Thomas Williams"
>
>>For remote controls that have been properly cleaned out and still
>>don't work like new, I understand some conductive material needs to be
>>coated onto the circuit board contacts on the inside of the pad
>>buttons. Reviewing web discussions of this I wonder if a good approach
>>may be to mix graphite in silicone glue and lightly coat the surface
>>of the pad's underside. Anyone tried this or have a thought on it?
>
>
>
> ** Think the graphite might simply dissolve in the silicone adhesive and the
> surface remain non conducting.
>
> Conductive glues are rare animals for this reason.
>
> Why don't YOU try it ??
>
>
>
> .... Phil
>
>
>
>
>
>
http://www.wikihow.com/Repair-a-Remote-Control

== 4 of 7 ==
Date: Sat, Jan 8 2011 5:17 pm
From: "Phil Allison"

"Jamie the Radio Ham "

** Post only to the OP - you fucking, fuckwit.

I'm not the one with the problem.

..... Phil

== 5 of 7 ==
Date: Sat, Jan 8 2011 6:05 pm
From: Jamie

Phil Allison wrote:

>
> I'm not the one with the problem.
>
Are you sure ?

>
> ..... Phil
>
>
>

== 6 of 7 ==
Date: Sat, Jan 8 2011 6:05 pm
From: "Phil Allison"

"Jamie the fuckwit Radio Ham "

** Post only to the OP - you fucking, fuckwit.

The OP has the problem.

..... Phil

== 7 of 7 ==
Date: Sat, Jan 8 2011 7:36 pm
From: Jeff Liebermann

On Sat, 8 Jan 2011 11:49:26 -0800 (PST), Thomas Williams
<twillia0@gmail.com> wrote:

>For remote controls that have been properly cleaned out and still
>don't work like new, I understand some conductive material needs to be
>coated onto the circuit board contacts on the inside of the pad
>buttons. Reviewing web discussions of this I wonder if a good approach
>may be to mix graphite in silicone glue and lightly coat the surface
>of the pad's underside. Anyone tried this or have a thought on it?
>Others have used electrically conductive paint (e.g., that purchased
>at auto supply stores to reconduct broken rear window defrost
>circuits) but that would not seem to be as flexible as silicone glue
>with conductive material mixed in it. I did read where someone mixed
>finely shredded copper (from pipe) with thinly diluted white glue and
>it worked well (but for how long?). It would seem that the latter
>approach would be better if silicone glue was used, as it is more
>flexible. What ye think?

I use conductive paste:
<http://www.hifi-remote.com/manuals/p8/rs-rf.shtml?15-1995#wornout>
<http://www.permatex.com/products/automotive/specialized_maintenance_repair/auto_glass_lens_repair/Permatex_Quick_Grid_Rear_Window_Defogger_Repair_Kit.htm>

If available, I've also used Aquadag (water based graphite paste).
<http://en.wikipedia.org/wiki/Aquadag>

Before you attack, clean both the graphite button bottom and the gold
contacts on the PCB with alcohol. It might just be grease on the
contacts.

The problem with mixing your own conductive graphite concoction is
that only a few formulations are actually conductive. If you don't
add enough graphite, or the graphite particles are too small, they
will not touch each other and therefore will not be conductive. I've
tried to make my own conductive glue with powdered aluminum and epoxy.
It failed badly and was mostly an insulator. I eventually got it to
conduct by radically adjusting the aluminum to epoxy ratio, but with
little epoxy to act as a binder, it was terminally brittle.

Anyway, try it. You might get lucky and find the right combination of
grain size and graphite to glue ratio. Test with an ohms guesser.
Your remote should work with anything less than about 1,000 ohms per
square, but I'm guessing:
<http://en.wikipedia.org/wiki/Sheet_resistance>

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

==============================================================================
TOPIC: Bad cap outcomes
http://groups.google.com/group/sci.electronics.repair/t/ec9df43e004018a7?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 8 2011 1:03 pm
From: Baron

Jeff Liebermann Inscribed thus:

> On Fri, 07 Jan 2011 20:23:19 +0000, Baron
> <baron.nospam@linuxmaniac.nospam.net> wrote:
>
>>> <http://802.11junk.com/jeffl/pics/drivel/slides/diploma.html>
>>> This is from about 1987.
>
>>Hey Jeff, can I use that ! Big Grin.
>
> Sure. Unfortunately, the "Certificate Maker" program I used to create
> it only ran on a Mac Plus on System 6. I still have the program
> somewhere, but the Mac got turned into a fishbowl after it blew up its
> third or fourth flyback xformer. Feel free to use the JPG. If you
> want a better scan, I have the original framed and hanging above my
> desk where the customer can't miss seeing it. I have yet to find a
> modern program that made stock certificate borders as nice as the
> original 1987 Mac program.
>

They say great minds think alike. That is exactly what I had in mind.
A nice framed print, conspicuously placed.
I think its great ! (*)
Thank you:

--
Best Regards:
Baron.

==============================================================================
TOPIC: Recharging li-on batteries
http://groups.google.com/group/sci.electronics.repair/t/94315ad5a39e6e04?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 8 2011 1:45 pm
From: news@jecarter.us

On Fri, 7 Jan 2011 20:31:59 -0800 (PST), klem kedidelhopper
<captainvideo462009@gmail.com> wrote:

>I just was given two 36 volt Dewalt drill batteries that would not
>take a charge. I opened them up and found what looks like the charger
>unit built right into the battery pack. These batteries are about the
>size of C batteries but a little bigger. They measure about 3.2 volts
>apiece. I know that these are li-on cells because there are 8 monitor
>wires going into the charger unit. One pack has one bad battery and
>the other has several bad ones. I also have a set of these type of
>batteries that came out of a laptop. The shame of it is I really can't
>do anything with any of these good cells because I have no way to
>recharge any of these. Does anyone know of a generic charger for li-on
>cells or some way that I can recharge these? Thanks, Lenny

You can build a single-cell charger for under $20. SparkFun has the
basic Li-Ion/LiPoly charger unit for $10 and you can power it froma
USB port on your computer or one of the plug-in USB power packs (~$5).
http://www.sparkfun.com/products/10217

John

==============================================================================
TOPIC: Where to find (affordable) Oven Set Control G.E.
http://groups.google.com/group/sci.electronics.repair/t/1cb36c021a0afb59?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 8 2011 3:22 pm
From: Vacillator

Update : Today I took off the front panel and all the screws,
etc, and actually got a look at the oven set switch. I had to remove 2
phillips head screws on the front of the switch to get it off the
panel. I could see into the switch a little bit through a hole, and
saw the shaft turn, but that was all I could see. I poked around at
the terminals to see if any were loose. Everything seemed to be tight,
and everything looked nice and shiny and new, surprisingly. I made
sure to touch all the connections, and jiggle all the wires on the
back of the oven set switch, and also on the thermostat, hoping to
"freshen up" any corroded or arced connections. I tested it after
reassembling it, and it was working normally again.

I'll have to use it a few more times, and see if it keeps working
properly.

==============================================================================
TOPIC: UPS battery life
http://groups.google.com/group/sci.electronics.repair/t/b73fd839ce17fb50?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Jan 8 2011 5:23 pm
From: Andrew Rossmann

In article <MPG.278a5d698320a03498976c@news.eternal-september.org>,
andysnewsreply@no_junk.comcast.net says...
>
> I have a battery I bought for an APC UPS about 4 years ago. I bought 2,
> and used one immediately. I kept the other on the side as I have several
> UPS's that use basically the same battery. Of course, over time, it has
> discharged itself. I measured about 4.3V instead of the normal 12-13V. I
> put it in a spare UPS, which immedialy complains if I try to turn it on.
> Luckily, the UPS charges even when it is off, but slowly. I measured
> about 15mA initially, and after about 36 hours, about 7.5mA. It is
> currently up to about 10.7V.
>
> How much damage do you think was done to the battery? I know it will
> lose some capacity.

Just a note that on that dead battery, the manufacturer date code (how
to read the code was on the PowerSonic web site) was from December 2002,
and it had never been used. No wonder it was dead!

I went and bought 2 replacement batteries. I should have done my
homework first and looked at what was actually in the UPS's. The battery
I found on-line was a PowerSonic PS-1270. This is a basic, 12V 7AH
battery. They are dated from October and November of 2010. The battery I
took out of the UPS, after removing the APC label, was a BB Batttery
HR9-12. This is a 9AH HighRate. The PowerSonic equivalent would be the
PSH-1280FR. The date code for the BB battery is DD021018. Haven't found
how to read that, yet.

Just how much life will I lose with these 7AH batteries, and do you
think the HR rating will make a difference? The UPS is rated 725VA,
although I only have a VCR and cable box plugged into it the backup
section.

Costwise, it wasn't too big a deal. The 2 batteries ($14 each) and
shipping ($13 for the pair) were about the same as buying a single
genuine APC battery. I bought them from PortablePower.com, via Amazon.
They do have the PowerSonic 1280 for $20.50. Any suggestions for any
other brand that you may trust more?

--
If there is a no_junk in my address, please REMOVE it before replying!
All junk mail senders will be prosecuted to the fullest extent of the
law!!
http://home.comcast.net/~andyross

==============================================================================

You received this message because you are subscribed to the Google Groups "sci.electronics.repair"
group.

To post to this group, visit http://groups.google.com/group/sci.electronics.repair?hl=en

To unsubscribe from this group, send email to sci.electronics.repair+unsubscribe@googlegroups.com

To change the way you get mail from this group, visit:
http://groups.google.com/group/sci.electronics.repair/subscribe?hl=en

To report abuse, send email explaining the problem to abuse@googlegroups.com

==============================================================================
Google Groups: http://groups.google.com/?hl=en

Electronics

sci.electronics.repair - 25 new messages in 10 topics - digest

No Response to "sci.electronics.repair - 25 new messages in 10 topics - digest"

Post a Comment

Blog Roll

Blog Archive