Toshiba TV29C90 problem; Image fades to black...

"JANA" <jana@NOSPAMca.inter.net> wrote in message
news:j5-dnTDdnM1tzunVnZ2dnUVZ_ovinZ2d@posted.uniservecommunications...

These low cost surge protectors are not very good. Your best bet is a
UPS. This way if there is a power cut, your computer will be protected.
You will have a few minutes to save your work and shut down the
computer. If there is a strong surge from lightning, there is not very
much you will be able to do about it.

According to international standards for Europe, North America, and many
other countries, all power supplies must have some type of built in
surge protection. They do the best they can at a reasonable cost.

In reality, when the power company distribution takes a hit, anything on
the AC mains line can be damaged. A little box with a few varistors is
not going to do anything much for you unless it is very elaborate in
design. This will cost a lot more than you would be willing to pay. If
the power lines delivering power to your home get a lightning hit, there
is no way a small surge protector or a small UPS will help. The only
thing you can count on is that the ground on the power entry of your
home does its best to absorb as much as possible.
Click to expand...

This is, to say the least, incomplete and unduly pessimistic. The writer
appears to be mouthing half-truths and platitudes; I don't think he has the
least idea what he's talking about.

Any protection is better than none, and as you add surge suppressors around
the house, you get additional protection for everything on the same circuit
(and to a lesser extent, on other circuits).

Twenty years ago, PC Magazine regularly tested surge suppressors. They no
longer do, so there's no way of knowing which are good and which are
ineffective. I have a lot of $80 Belkins that were purchased for $20 or less
from buy.com. I've never had a problem, but then, I have no idea of what
_might_ have happened if they hadn't been connected. *

Some manufacturers offer a warranty that states that, if your equipment is
damaged _and_ the surge suppressor itself is damaged, they will repair or
replace your equipment.

What is commonly called a UPS is actually an SPS. A true UPS would provide
fairly good surge suppression, because it replaces the line voltage with its
own internally generated voltage all the time. An SPS does this _only_
during a brownout or full loss.

You need surge suppressors for anything electronic, and an SPS or UPS for
your computer.

* The only damage anything I owned suffered was a lot of blown
semiconductors in an answering machine using discrete devices. (I fixed it
by systematically replacing shorted or suspect Qs and Ds.)
 
On Wed, 09 Jul 2008 17:01:28 -0400, John Hudak wrote:
Wild_Bill wrote:
Hi, I've been looking at some new low-cost handheld scopes, but would
like to know of some models (under $1000US) that various users would
recommend for various reasons, not just low cost.

I'm in the US, and I don't need a rugged model for everyday
service/repair shop-type use. I already have bench-type scopes, but I'd
like to have one that I can use at my desk for quick checks in small,
and generally low-voltage devices.

I'd like to find one that is portable, battery operated, and one that
every feature isn't microprocessor controlled (ones with real switches
and fewer menus).

I'm familiar with the concept of "you only get what you pay for", and I
may need to buy more than one to eventually attain the one that is most
suitable to me.

Well, you don't say anything about the number of channels you want or
the frequency range...and....
Click to expand...
Yup. With the specs provided by the OP, this pretty well fits the
bill:
http://www.twenga.co.uk/offer/0208558557.html
 
"saurabh9" <saurabh9@gmail.com> wrote in message
news:bcea3d6c-af5e-42e3-86cf-15fe8c05a1d1@d77g2000hsb.googlegroups.com...
Hi,
Please have a look at the circuit at:
http://www.glacialwanderer.com/_blog/blog2008/04_April/hb_relay5.jpg.
It is from the article at
http://www.glacialwanderer.com/hobbyrobotics/?p=9.

The circuit it to turn on or off a AC bulb by a microcontroller. My
question is, can we somehow safely add a manual override switch near
the bulb, so that even if the microprocessor is not working, we can
turn the switch on/off manually? If yes, how will the circuit then
look like?
Sorry if this is a simple question as I am just starting in
electronics and electrical circuits.
Click to expand...
There should be no problem just adding a switch across the upper and lower
relay connections on the right hand side of the square marked "relay" for a
manual over-ride. It then doesn't matter what the relay is doing. It does
mean, however, that once you've turned the lamp on with this switch, the
microprocessor has no further control over the lamp, until you turn the
manual switch back off. Is that what you need to happen ?

Arfa
 
In article
<bcea3d6c-af5e-42e3-86cf-15fe8c05a1d1@d77g2000hsb.googlegroups.com>,
saurabh9 <saurabh9@gmail.com> wrote:
Hi,
Please have a look at the circuit at:
http://www.glacialwanderer.com/_blog/blog2008/04_April/hb_relay5.jpg.
It is from the article at http://www.glacialwanderer.com/hobbyrobotics/?p=9.

The circuit it to turn on or off a AC bulb by a microcontroller. My
question is, can we somehow safely add a manual override switch near
the bulb, so that even if the microprocessor is not working, we can
turn the switch on/off manually? If yes, how will the circuit then
look like?
Sorry if this is a simple question as I am just starting in
electronics and electrical circuits.
Click to expand...
Do you really mean two way switching? That circuit means either switch
over-rides the state of the other. Like in hall lights. So your relay
controlled one might switch the light off if already on or on if already
off. The circuit for that is below - but the relay needs to be a
changeover type with three contacts.



L1 L1
0===========0 0===========0============= Line
| \ / |
C 0================================O C
\ / \ /
0===========0 0===========0============= Switch return
L2 Optional L2
Intermediate

If, however, all you wish to do is make sure the light can be switched on
regardless of the relay state, add a switch in parallel to the relay
contacts.

--
*Time is fun when you're having flies... Kermit

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.
 
What are you going to do with it? You could spray a conductive paint
on regular masking tape, for example.

It is going to be used to hold down LCD displays and lithium batteries. I
don't
think regular vinyl tape would suffice without leaving a mess of glue
residue? I
would think conductive paint will be more expensive and an extra step.

At this point in time I will be using the tape doing iPod repairs. I don't
want
a mess to deal with when I get back into them at a later date.
Click to expand...
I'm not sure what anti-static tape _is_, in the first place. (Is it tape
that doesn't generate an electrostatic charge when it's pulled off the
roll?) Nor am I sure what use it would have in the application you mention.

My initial reaction is that you're looking for something you don't need.
 
As usual, the Lady from Philadelphia has to step in and resolve this issue.

It would be a simple matter (as someone else mentioned) to use single-pole,
double-throw switching at both ends to permit either computer control or
local control of the light. (This type of switching has been in use -- I'd
assume -- close to a century. You should be able to find a schematic in any
book on household wiring. It's trivial.)

The "catch" is that the switch positions no don't directly correlate with
whether the light is on or off. (I normally wire the switches so that when
both are up or both are down, the light is on.) So closing the relay
operated by the microcontroller will turn the lamp on or off, depending on
the position of the local switch. Do you understand that?

If this ambiguity isn't a problem, then simply wire up the system as any
two-way lighting system, and you'll have full control at both ends. You just
won't know whether closing the microcontroller relay turns the light on or
off.

Note that if you add a manual _override_ at the light's location, that
_forces_ the lamp on, then the microcontroller _won't_ be able to shut it
off. I don't think that's what you want.
 
"EADGBE" <hwbosshoss@comcast.net> wrote in message
news:fae88ad4-007a-4d8e-9165-18c1f1cd4e7f@l64g2000hse.googlegroups.com...
I have a Yamaha CX-1000 preamp and I just acquired a used Yamaha CD
player that has a digital output (CDX-710).

The CX-1000 preamp has digital inputs on it. Even though this CD
player sounds fine through the analog outputs, I wanted to hear what
the digital output sounded like.

I used a Monster Cable Datalink SP/DIF cable I had lying around to
connect the two.

PROBLEM: I get perfect audio through the left channel, but nothing at
all in the right channel. Needless to say, the CD player sounds great
in BOTH left & right channels when I use its analog outputs.

What could the problem be? I am unfamiliar with making digital
connections. Could I be using the wrong kind of cable? If there is a
breakdown somewhere, what would be the most likely problem?

I was always under the impression that digital, by definition, either
works or it doesn't. But I have a situation where "half" of it works
and the other "half" doesn't.
Click to expand...

You cannot lose "half " of a serial data stream. The problem must be in the
preamp, somewhere between (and including) the D/A converter, and where its
output joins the analogue circuitry.



Gareth.
 
"Adrian C" <email@here.invalid> wrote in message
news:6dmru5F3ddkhU1@mid.individual.net...
EADGBE wrote:
PROBLEM: I get perfect audio through the left channel, but nothing at
all in the right channel. Needless to say, the CD player sounds great
in BOTH left & right channels when I use its analog outputs.

What could the problem be?

Fault in the preamp, I'd wager. Do you have anything else with a digital
output you could try?

--
Adrian C
Click to expand...
Agreed that you need to try something else as an input. Problem could be at
either end in that both channels may not be making it into one data stream
at the CD (unlikely) or (more likely) that the Yammy is either failing to
decode the missing channel, or failing to switch it. Do you have only a
coaxial digital connection ? Is there an optical one that you could try ?
Either coaxial or optical, you are correct in your assumption that it should
all "just work" as soon as you make that one connection.

Arfa
 
In article <6dmvj0F3d369U1@mid.individual.net>,
Adrian C <email@here.invalid> wrote:
Don't know how other posters have turned this into a two-way light bulb
and intermediate hall/stairway switching situation....
Click to expand...
That's what's the subject says?

Besides - we haven't been told what the circuit is for. Could be a
wireless remote switch in which case a two way circuit would be fine.

--
*A closed mouth gathers no feet.*

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.
 
EADGBE wrote:
I have a Yamaha CX-1000 preamp and I just acquired a used Yamaha CD
player that has a digital output (CDX-710).

The CX-1000 preamp has digital inputs on it. Even though this CD
player sounds fine through the analog outputs, I wanted to hear what
the digital output sounded like.

I used a Monster Cable Datalink SP/DIF cable I had lying around to
connect the two.

PROBLEM: I get perfect audio through the left channel, but nothing at
all in the right channel. Needless to say, the CD player sounds great
in BOTH left & right channels when I use its analog outputs.

What could the problem be?
Click to expand...
The problem is a fault in the sending device, or the receiving device.


geoff
 
"jakdedert" <jakdedert@bellsouth.net> wrote in message
news:7aPdk.25998$PZ6.8511@bignews5.bellsouth.net...
mw210461@gmail.com wrote:
snip

What else should I try to isolate the problem? Cut the power line of
all my neighbors?

Thanks a bunch!
michael

Sounds suspiciously like what my WiFi router does to my 2.4gig video link.
If you have a laptop with wifi, try checking for a signal in your
area...or ask a friend to bring over his laptop, if not.

jak
Click to expand...
Could well be from a neighbour's WiFi. As well as my own, I can see three
other networks on my machines, one of which is stronger at one of my
locations, than my own network ! You could try rotating a large saucepan lid
around the video link receiver to see if the interference is minimised at
any point. That will then tell you the direction that it's getting in from.

Arfa
 
Could well be from a neighbour's WiFi.
Click to expand...
I agree, that's the most likely.

Most WiFi access points send out a "beacon" packet every 100
milliseconds or so, even when they have no associated clients - this
is how client systems can "see" them, and send a request-to-associate.

I tried a 2.4 GHz wireless video sender/receiver system a few years
ago, and quite quickly gave up on it. It was bothered by WiFi, by a
2.4-gig frequency-hopping spread spectrum cordless telephone, and by
every microwave oven within half a block.

Between that interference, and the fact that the sender had difficulty
getting a reasonably clean video image through just three sheet-rock
interior walls, I gave it up as a bad job and ran a "composite video
plus stereo audio" cable through the ceiling.

--
Dave Platt <dplatt@radagast.org> AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!
 
The problem is a fault in the sending device, or the receiving device.


geoff

That narrows down the possibilities! At least he knows it's not the cable
Click to expand...
(obviously)
 
"Mike S" <nospam> wrote in message news:4878627d$0$11601$607ed4bc@cv.net...
The problem is a fault in the sending device, or the receiving device.


geoff

That narrows down the possibilities! At least he knows it's not the cable
(obviously)
Click to expand...

Could someone please explain how it could be possible to lose one channel of
the digital stream out of the CD player, considering that the CD's audio
output is perfectly OK.



Gareth.
 
"Don Pearce" <nospam@nospam.com> wrote in message
news:X8udnTsGxvX98OXVnZ2dnUVZ8qPinZ2d@posted.plusnet...
Gareth Magennis wrote:
"Mike S" <nospam> wrote in message
news:4878627d$0$11601$607ed4bc@cv.net...
The problem is a fault in the sending device, or the receiving device.


geoff

That narrows down the possibilities! At least he knows it's not the
cable (obviously)



Could someone please explain how it could be possible to lose one channel
of the digital stream out of the CD player, considering that the CD's
audio output is perfectly OK.



Gareth.

Depends on the internal architecture, but I have to agree it is highly
unlikely.

d
Click to expand...


I would say close to Zero. I'll bet nobody here can cite a case where this
has actually happened.



Gareth.
 
"Gareth Magennis" <gareth.magennis@ntlworld.com> wrote in message
news:3h_dk.25396$E41.2252@text.news.virginmedia.com...
"Don Pearce" <nospam@nospam.com> wrote in message
news:X8udnTsGxvX98OXVnZ2dnUVZ8qPinZ2d@posted.plusnet...
Gareth Magennis wrote:
"Mike S" <nospam> wrote in message
news:4878627d$0$11601$607ed4bc@cv.net...
The problem is a fault in the sending device, or the receiving device.


geoff

That narrows down the possibilities! At least he knows it's not the
cable (obviously)



Could someone please explain how it could be possible to lose one
channel of the digital stream out of the CD player, considering that the
CD's audio output is perfectly OK.



Gareth.

Depends on the internal architecture, but I have to agree it is highly
unlikely.

d



I would say close to Zero. I'll bet nobody here can cite a case where
this has actually happened.



Gareth.
Click to expand...
It is very unlikely, I agree, but then in these days of extremely complex
internal architecture of most LSIs, there isn't much in the way of 'stock
faults' any more, and strange ones happen every few weeks in my experience.
That being the case, none of us could cite a case of a peculiar fault, until
it actually happened :)

Unlikely or not, there is the remote possibility that this could be the one
for that fault ... I don't know if the PCM data stream coming off the disc
is decoded and processed first, or whether it is directly transcoded into
SPdif (or indeed, whether SPdif is just PCM under another name - I've never
bothered to check because it's very rare to get *any* fault in this area).
If there is any decoding going on, then just maybe, a channel *could* be
lost. But yes, in practical terms, almost certainly a problem in the amp.

Arfa
 
The Lady from Philadelphia sez...

Why are you arguing about such an unlikely event when the OP hasn't tested
the unit with another digital source?
 
"Gareth Magennis" <gareth.magennis@ntlworld.com> wrote in message
news:d1_dk.25387$E41.23300@text.news.virginmedia.com...
"Mike S" <nospam> wrote in message
news:4878627d$0$11601$607ed4bc@cv.net...

The problem is a fault in the sending device, or the receiving device.


geoff

That narrows down the possibilities! At least he knows it's not the
cable (obviously)



Could someone please explain how it could be possible to lose one channel
of the digital stream out of the CD player, considering that the CD's
audio output is perfectly OK.
Click to expand...
Yes. In the digital output the left and right channels are combined into
one digital stream, then sent over the coax cable to the receiver/preamp
where they arer separated into the two analog channels.
The problem here is in one of those stages. Either one of the channels is
being lost before it is encoded into that digital stream to be sent out of
the CD player, or a perfect digital stream is being sent to the preamp and
sometime after it is decoded into the two seperate channels, one channel is
lost due to a faulty component or a bad solder joint, loose connection, etc.
 
"EADGBE" wrote...
I have received a couple of comments here that my cable choice could
be the problem.

Is it actually possible that a cheaper cable could solve the problem?
Click to expand...
NO they are joking. Since the same cable carries both the left and
right channels it is impossible that a passive device such as a cable
could reliably distingusih between the left channel data and the right
channel data in the stream.

And here is a question that will really show my level of ignorance
when it comes to digital audio formats: Is it possible that I am using
the wrong kind of digital cable?
Click to expand...
NO. It either works or it doesn't. It is as simple as that. People
might argue that if you use really poor cable it might introduce such
digital artifacts as "jitter". But there is no amount of arm-waving
that can explain how it could affect only one channel of the
interleaved data.

The digital output of the CD player
and the digital input on the preamp are both RCA type jacks. I simply
thought that using a digital coaxial cable with RCA plugs on both ends
would be appropriate. Am I wrong? Is there another type of cable I
should use that will fit?
Click to expand...
It is NOT the cable. Ignore the frivolity and go back to doing a proper
differential diagnosis with the source and destination equipment.
 
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