Toshiba TV29C90 problem; Image fades to black...

[Active8]

In article <1i75b.1646$P51.5015@amstwist00>, Zak@spam.invalid says...

Jim Thompson wrote:

When we returned she told us that, when using our shower, it sometimes
felt like an electrical shock.

A little metering revealed 15VAC between the shower head and the
drain.

In Arizona "ground" is established by bonding water pipes to incoming
neutral (but not the sewer piping).

Aagh!

Around here (Netherlands) ground and neutral are totally different
things. Consumers are not supposed to be interested in which of the plug
pins is neutral; could even be 2 x 115 volts in some places.

and then there's polarized plugs... even on some old lamps.

The installer is supposed to know what is hot - that's the side the
light switch goes on.

Still goes wrongs sometimes: last case making the paper was a 'ring
ground' connecting different houses to a single ground pen someplace -
which had failed.

ring ground for housing. that's a new one on me. of all crackheaded
ideas!

Then there's folks putting a srew from the lamp fixture below into a
shower drain, causing leak, wetness, and leakage. Not good.

OTOH all metal objects in bathroom space need to be wired together in a
way that is easy to inspect - at least for newly built homes.

i forgot to wire in the toilet paper holder. will i fry?

Connecting ground to water is also not allowed for new buidings.

i'd have never, since age of maybe 6 when i understood electric shock
from ben franklin's kite, ever thought of designing a lightning rod out
of some poor schmuck's plumbing. nowdays, of course, they're running
plastic water hose out of plastic manifolds at the entry.

as long as i'm not showering on a ground rod, i'm ok.

A
separate ground pin in the earth, wired to a separate net in the home,
is what it should be. Never connected to neutral.

Where do people connect neutral to ground by design?

in USA a new load center box's earth/safety bus is bonded to the rod and
jumpered to the neutral bus. trust me, that's good practice, thus the
code.

old house wiring is always suspect.

towns with delta systems powering old neighborhoods where the houses are
totally rigged up messes... scary.

you can be an out of town landlord with crap everything.

the govt has programs to help bring wiring up to code under different
housing programs. i like that.

brs,
mike

Thomas

 

[N. Thornton]

Hi

Localized surges can happen if the power is shared with other
massive
items that inductively switch out and in rapidly. Pow!

Active8:

that's one of the first suspects that came to mind when i started
reading this thread. i can picture a house with crappy wiring blowing
stuff up when the washing machine's running.

The house was recently built, no visible alterations. Both washing
machines and TVs have suficient filtering built in to avoid such
damage: both would have to be wired over, _and_ a high impedance
inserted to the rest of the supply and loads before this would kill
sets. I cant see it.

or a bad cockroach problem :-0 bunch of filthy old sets?

they were dirty inside, but even so the failure rate was still 20%,
which pans out at 1 in 15,000 for 6 sets to die by chance. I suppose
its not quite impossible.

cockroaches... the house was clean and modern, again I can't see it.

Where do people connect neutral to ground by design?
Thomas

Here in Britain a lot of our supplies are like that, its caled PME, or
protective multiple earthing. The power co earths neutral at multiple
locations to make it safe enough for use as a protective earth.

or a 3-phase appliance with a fault on one phase causing weird stuff.
mike

good point, but it was a big housing estate, there would have been no
3 phase supplies or loads.


Still stumped. I'm beginning to think it may have been any one of
those rather unlikely (but not impossible) scenarios.


Regards, NT

 

[Frank Bemelman]

"N. Thornton" <bigcat@meeow.co.uk> schreef in bericht
news:a7076635.0309030226.18182776@posting.google.com...

Still stumped. I'm beginning to think it may have been any one of
those rather unlikely (but not impossible) scenarios.

Are these folks watching television now, or did they buy
a tropical fishtank to watch instead? It would be amazing
if all the fish died

--
Thanks,
Frank Bemelman
(remove 'x' & .invalid when sending email)

 

[Tom Del Rosso]

Jim Thompson wrote:

I think I've confused you with neutral, which around here is supposed
to be "ground". Then there's "common" which is like ground but not
connected to ground ;-)

Ground is ground
the world around
except in England
where it's earth.

(I'm not saying it's true exactly, but it's an old rhyme I heard.)


--
-Reply in group, but if emailing please add two more zeros and delete
the obvious-

 

[Dave VanHorn]

70v? Is that on a 120v line or 240? Either way that's a big enough drop
that
I would think a call to the utility would get it fixed up in short order.

110 line. you'd think so, but it wasn't. everyone in the area had variacs
on their tvs, which they dialed up or down according to the size of the
picture on the screen.

 

[jakdedert]

"petrus bitbyter" <p.kralt@hccnet.nl> wrote in message
news:1PM4b.7266$Xh6.1997077@amsnews02.chello.com...

snip

Havig no real information about this case, we can speculate through all
eternity. Here is one: Did the customer have the bad habit of switching
the
set off and on rapidly? A lot of TVsets, even new ones, will not survive
this treatment for long.

pieter

This is unavoidable on many sets these days. The stupid switches are so
sensitive that it's very easy to toggle the set on/off with one quick push.
On almost every TV in my household (six or seven, I've lost count), one must
'very' positively push and hold the switch for a second to turn on or off.

The problem is compounded by the fact that a lot of newer sets have no pilot
light of any kind. The only positive indication of power on is when the CRT
heats up enough to give a display. I've turned on/off/on many times,
because I though I hadn't pushed the switch hard enough the first time.

jak

---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.511 / Virus Database: 308 - Release Date: 18-8-2003

 

[Walter Harley]

"Active8" <mcolasono@earthlink.net.invalid> wrote in message
news:MPG.19bf6c6a8a755d4698981f@news.east.earthlink.net...

i forgot to wire in the toilet paper holder. will i fry?

Only if you wipe.

 

[RonKZ650]

First, make sure you have about 25v on pins 6 and 3 of the LA7832. If missing,
trace back from pin 6 to find an open resistor that should be about 1.2 ohm,
then check the diode feeding the resistor for a short. If it's not shorted
replace the LA7832, (use a LA7833 for replacement), and the resistor. If 25v is
present on the IC, just replace the LA7832. (use a LA7833 instead of a 7832).
Make sure one of the caps you changed is the one between pins 3-7 of the chip.
This is the one that causes the chip to fail.
Ron

 

[Walter Harley]

"N. Thornton" <bigcat@meeow.co.uk> wrote in message
news:a7076635.0309030226.18182776@posting.google.com...

even so the failure rate was still 20%,
which pans out at 1 in 15,000 for 6 sets to die by chance. I suppose
its not quite impossible.

Intuitively, I'm with you. But still, to play devil's advocate: you'd
expect to see something that happens once in 15k times, every now and then,
if you stay in the field. Calculate the odds of *never* seeing a 1-in-15k
occurrence, if you take (say) 10k samples; how many sets did that shop sell
over the years? And indeed, a relatively rare occurrence is even more
likely to come to your notice than it would by random chance, because it's
more likely to get mentioned. (Thus, we all hear about lottery winners,
even though they are so rare compared to losers.)

Seventh one's the charm! ;-)

 

[Arthur Jernberg]

Your best resource may be to try a Canon repair facility or their web site.
"jack" <jankro@vip.fi> wrote in message
news:xXl5b.2605$ZB4.358@reader1.news.jippii.net...

Greetings,

I have a Micro fuse type D1600 and I cannot find any info on it. It is a
main fuse on a Canon UC5000 camera. It is a small roud cannister, almost
like a small capacitor.
Anybody have idea what size fuse this is?

Thanks,

Jan/Finland

 

[u1061771156]

In article <3f564693$0$23667$65c69314@mercury.nildram.net>, Graeme wrote:

Hi

I've got an old VCR that I thought I'd like to get working, but I think I
need to know the following. On the underside of the drive mechanism there is
a 4-pin connector which connects between some sort of rotary encoder and the
main circuit board. The transport is currently in the eject state and I need
to know what the default setting for the encoder is (I've been just a little
stupid and removed this without noting how it was aligned). There is an
arrow on the encoder's plastic disc but nothing obvious to line it up with
on its housing. Any help or pointers would be great. Thanks.

Sounds like a 'K' deck machine.

Newer mode switches have a line marked on the stator. Apparently some older
ones didn't!

With the deck upside-down, cassette slot towards you (so the loading
motor is towards you and on your left), the triangle on the mode switch
rotor should be at a "2 o'clock" position when the rest of the mechanism
is in the correct position (all alignment marks on other gears line up).

I think for this deck alignment is done in the "cassette loaded" state.

If you're still stumped I have a diagram which I could scan for you.

Mike.

 

[Louie]

Tweetldee wrote:

I'll bet that if break the circuit at pin 5, and you switch your external
composite video into the circuit at that point, you should see it on the
screen. You may have to do a little level-shifting to restore the DC level
to what the sync separator wants to see. The waveform WF1 is what the
KA2915 puts out from pin 5. Your external video should closely approximate
that waveform.

well that should be easy enough, because there's a jumper wire right off
of pin 5. but i'm not sure how to shift the level. supposedly if i put
the signal through a transistor and adjust the feed level then i can
make it to agree with the level it needs to make it work.
does it have to go across a cap?
and does the xternal wire have to be shielded?

thanx, louie

 

[Arthur Jernberg]

Zounds: Time to have it drop kicked or take it to your local service dealer,
Eh!! If the part indeed is NLA then ask SONY what their recommended fix is.
We can furnish a plouthera of ideals and never have our hands and expertise
inside of your particular tele. It is then up to you to do the actual
mechanical and electrical repairs. If not able then it may be time to call
in the profesionals. Not to be a kill joy but enuf is enuf?? At least IMHO ,
Eh?/
"Bill" <elect21st@aol.com> wrote in message
news:8fb59540.0308311512.1606582e@posting.google.com...

I have a Sony KV32XBR10 with sound problems. I'm trying to bypass
SBX1593 which is NLA, but NOBODY seems to know where it is exactly on
this chassis !! Is it similar to SBX1637 which I replaced many times ?
Every time I go back to this set and look around with lights and
magnifier but still can't find it ! I would like to hear from someone
who actually did the bypass and knows for sure. Thanks !

 

[Tweetldee]

"Louie" <beavisnbutthead@softhome.net> wrote in message
news:6Yu5b.347716$uu5.68877@sccrnsc04...

Tweetldee wrote:

I'll bet that if break the circuit at pin 5, and you switch your
external
composite video into the circuit at that point, you should see it on the
screen. You may have to do a little level-shifting to restore the DC
level
to what the sync separator wants to see. The waveform WF1 is what the
KA2915 puts out from pin 5. Your external video should closely
approximate
that waveform.

well that should be easy enough, because there's a jumper wire right off
of pin 5. but i'm not sure how to shift the level. supposedly if i put
the signal through a transistor and adjust the feed level then i can
make it to agree with the level it needs to make it work.
does it have to go across a cap?
and does the xternal wire have to be shielded?

thanx, louie

Before we go off to design a level shifter, why don't you measure the DC
voltage at pin 5, so we can see if it even needs to be done. If it becomes
necessary, then a simple non-inverting op-amp stage with a DC offset trimmer
could be the ticket. But, first things first.
How good are you in circuit construction? Since we're talking about
handling video here, circuit layout, construction and shielding are
important. That answers your last question... yes, shielding is quite
important.
--
Tweetldee
Tweetldee at att dot net (Just subsitute the appropriate characters in the
address)

Time is what keeps everything from happening all at once.

 

[Mike Bates]

im looking for a new modual

the deflection/SMPS module.






"RonKZ650" <ronkz650@aol.comnospam> wrote in message
news:20030903185044.18140.00000535@mb-m05.aol.com...

It was only used in the SR3587DT and SR3589DT. They used a 9-1269 and
9-1268 in
the sets SR2789,3247, 3543 but being very similar, there are differences
to
compensate for the screen sizes.
Ron

Hello,
I went to order a schematic from Zenith for the
model SR3587DT and they told be it'd be a back order
for a month, which we all know is backorder code for
3 months to indefinitely

Anyway, since the board I'm working on is a 9-1270-03
I figger that if I could find out what other Models use this
board then, perhaps I could order the service manual for
one of these other models.

Big question is however, What other models use this
board of course?

I reckon I could use any model that uses a 9-1270

9-1270-1
OR 9-1270-2

9-1270-3

Any help, truly appreciated.

 

[Dave Moore]

Try reworking soldering in the tuner,
get two pair of 2.5 diopter glasses and cascade them
soze u can see the work you're doing and be very
careful not to solder bridge (connect) any two points that
shoudn't be connected.

I recommend just hitting the ground connections
where the tuner can/shielding spikes through the PCB at
various locations,and then see if that works first before
you tackle touching up any more of the circuitry since
the rest is rather delicate and no need messin with it
if it don't need fixin beyond this point if you aren't
experienced with delicate solder work.


If that doesn't work, get the part number off the tuner
and replace it, or send it off to be rebuilt.

=^^=DM

"Chris White" <chris@elliscomp.com> wrote in message
news:bj5gkl030d@enews3.newsguy.com...

I Have a sanyo tv for which I don't know the model number but the chassis
is
19730-02.

It seems to work fine for about 5 min then the channels start to get snowy
then eventually all snow. Also sometimes when I first turn it on some
channels dont work. I could use any help you could give.

 

[jack]

Thanks, I figured it out. 1600 means 1,6A, since it's the main fuse, it
sounds about correct.

Thanks anyway .

Jan

"Arthur Jernberg" <stubby@comcast.net> wrote in message
newsKWcnSHSvp4UwsuiU-KYvw@comcast.com...

Your best resource may be to try a Canon repair facility or their web
site.
"jack" <jankro@vip.fi> wrote in message
news:xXl5b.2605$ZB4.358@reader1.news.jippii.net...
Greetings,

I have a Micro fuse type D1600 and I cannot find any info on it. It is a
main fuse on a Canon UC5000 camera. It is a small roud cannister, almost
like a small capacitor.
Anybody have idea what size fuse this is?

Thanks,

Jan/Finland

 

[Dave Moore]

Try the question in the newsgroup sci.electronics.design


"Walter Craig" <walter@craig8607.freeserve.co.uk> wrote in message
news:bj2dkk$tjk$1@newsg1.svr.pol.co.uk...

Variac is a bit expensive. I have heard it can be done with a Triac. Can
any
one help with info.
Walter.
"ajb" <ajb@sphynxstopdemonstopcostopuk> wrote in message
news:e4c7lv0m2fd9uuhgejbo4rn5lnjb3653sq@4ax.com...
On Mon, 1 Sep 2003 21:10:55 +0100, "Walter Craig"
walter@craig8607.freeserve.co.uk> wrote:

Can I regulate the 240v input of a mains transformer in order to set
the
output to 7/14v of a 18v-40amp battery charger.
Without using wirewound resistance its wastfull and warm.
Thanks.
Cutty.


You could use a Variac (variable voltage transformer) on the input,
though unless you have one handy which would handle several hundred
watts (or _never_ turn it up too much on load!) it might be a bit
expensive. But surplus items do sometimes turn up cheap.....

And you'd lose some of the regulation and 'stiffness' of your charger
anyway, whatever method you used, though that might not matter.

AJB
--

Un-stop the address to reply, please.

If the 'self' is an illusion, who is being fooled?

 

[Dave Moore]

Great, I'll see if Zenith can cough up the
service manual for the SR3589DT
Thanks
=^^=DM

"RonKZ650" <ronkz650@aol.comnospam> wrote in message
news:20030903185044.18140.00000535@mb-m05.aol.com...

It was only used in the SR3587DT and SR3589DT. They used a 9-1269 and
9-1268 in
the sets SR2789,3247, 3543 but being very similar, there are differences
to
compensate for the screen sizes.
Ron

Hello,
I went to order a schematic from Zenith for the
model SR3587DT and they told be it'd be a back order
for a month, which we all know is backorder code for
3 months to indefinitely

Anyway, since the board I'm working on is a 9-1270-03
I figger that if I could find out what other Models use this
board then, perhaps I could order the service manual for
one of these other models.

Big question is however, What other models use this
board of course?

I reckon I could use any model that uses a 9-1270

9-1270-1
OR 9-1270-2

9-1270-3

Any help, truly appreciated.

 

[Dave Moore]

Ok here's an update,

I did rewind the coil (ref# LX3201) and while I did,
I measured the length of the wire and compared it to
the length of the wire on the older
Zenith coil p/n# 20-4284-01, and determined that
if you add 7-9 turns to it, it should work as a replacement
for the coil on the 9-1270 board.
Sorry I can't say
the part no# for the coil on the 9-1270 board as the top
of the part with the p/n# is missing.

Anyway, interestingly enough, the rewound origional coil
measured .39mh which was darn close to the 20-4284-01
coil which has approximately 8 less turns wich weighed in at
..38mh. Not surprising since I wound it rather imperfectly
by hand.

Ok, so then I added 8 turns to the 20-4284-01 and
measured it. It measured .48 mh which I'm guessing is
probably what a new coil for the 9-1270 board should
read.

Ok, the results? I put the 20-4284 coil with the additional
8 windings @ .48mh, in the set. The set now works better,
but still not quite right. The coil and the pincushion xstr
both run hot, but possibly acceptably hot. I just don't know.
Uncomfortable to the touch, but not boiling water.
Antone know? Is it the norm for these parts to run fairly
hot in these sets?

Before I reworked the coil, the set would work, but
shut down during bright scenes. Seems to be
overcurrent protect.

Now with the coil reworked, it still shuts down on
some really bright scenes, but it has a very much
obvious improvement in tolerance. In fact it might
run for 15 minutes or more.

I guess I'm going to have to get the schematic on this
one.

Oh, one thing I forgot to mention was,
I replaced the Flyback origionally. I ordered the
part from http://www.slelectronics.net/fl.zenith.htm#

I ordered the origional part p/n# 95-4134-28
and they sent me a 95-4134-11 which they claim
is a valid sub. The part had both numbers on it
and appears to be aftermarket.

I ordered a different flyback from them for a
Zenith PTV awhile back, and it worked just fine,
but they didn't give me a sub in that case.

Anyone have any opinions about whether this supposedly
valid sub could be the problem with this set?

Also.FWIW, I checked out the brightness limiter circuit,
best I could without a schema that is, and it seems to be ok.

Don't mean to go on so, basically I'm just speaking to the
archives here, which is why, as you may have noticed,
I put so many model and board numbers in the title.

Ok thanks.
=^^=DM



"Dave Moore" <novalves@nospamdatasync.com> wrote in message
news:bj5mvc$nhb$1@news.datasync.com...

Hello folks.
I came across this article by the great Dave D., about
rewinding these coils, ref.# LX3201

http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&selm=39F3266C.A54D88A9%40
locl.net

Being faced with this problem, I have decided to rewind rather than wait.
However, I have a few coils from older Zenith boards that I could just add
a few turns to.

Only, to do this, I need to know the inductance value to shoot for.

Anyone know what the value of this coil is supposed to be?

Thanks
=^^= DM