Toshiba TV29C90 problem; Image fades to black...

[sofie]

Not enough clues and observations in your posting.
If the compressor motor is running then you do not need to look at the motor
or associated components.... it might be low on freon.
If the motor tries to start but doesn't then look at the capacitor and/or
resistor.
If the compressor motor runs but does not run long enough then look at the
thermostat.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -


<paulodonohoe@yahoo.com> wrote in message
news:1112882594.735542.293100@l41g2000cwc.googlegroups.com...

Hi,

I have a Hotpoint freezer rza30 model.
The high temperature led comes on when it's plugged in and it's not
freezing.
There is a 25 ohm resistor block accross the condensor motor which
measures 25 ohms so it looks ok. There is also a 4 mf ac capacitor
across the mains input into the freezer. The capacitor has 2 terminals
coming out of the housing so I disconnected it and measured the
capacitance accross it which always measures 0. I am assuming this has
gone faulty. There is not really a lot else that I can see that might
me faulty. Any suggestions and am I on the right track?

Kind regards

 

[Don Bruder]

In article <0001HW.BE7980C700090142F04075B0@news.sonic.net>,
DaveC <me@privacy.net> wrote:

Underlying the key mechanisms is a double-sided film with concentric circuit
pads (for each key) on either side of the film. The key cap pushes down a
little inverted cone of what looks like silicone rubber to touch the film.

This isn't a contact switch; the top of the film has just one pad, as does
the bottom of the film; no electrical connection is being made.

Are you absolutely certain about that? It sounds to me like you're
describing a classic keyboard construction style.

The "AppleDesign" keyboard is one example - Three layers of clear
plastic (Mylar? Something else?). On the "inside" of the two outer
layers, conductors and contact pads are printed. The two outer sheets
are held apart by a third sheet of slightly stiffer plastic with holes
punched in it at the points where contact is expected to be made.
Hitting a key presses an inverted rubber cone like what you describe
onto the upper sheet, pressing the upper and lower layers together
through the hole at that locaiton in the center layer, completing a
circuit from the "top sheet" to the "bottom sheet".

On semi-casual visual inspection, the entire key matrix appears to be a
single sheet of plastic with printed circuit traces and contact pads
criss-crossing every which way. However, closer examination reveals it
to be a "sandwich" of three sheets with the contact pads very clearly
existing on the facing sides of two sheets, with a third "holey" sheet
between them to keep contact from happening anywhere except the desired
places.

If I were a betting man, I'd lay money that you've got exactly the same
concept going on with the keyboard you're looking at. It may be the most
common type of keyboard construction there is these days, short of an
array of individually packaged switches.

The connector to the motherboard is a 40-pin flexible mylar cable.

40 conductors sounds just about right for the type I'm speaking of. In
the AppleDesign, those 40 conductors - 20 from each layer of the
sandwich - get fed to a chip that takes care of converting each key-hit
into the serial datastream used by the four wire Apple Desktop Bus.

What brand of machine are we speaking of here, anyway?

--
Don Bruder - dakidd@sonic.net - New Email policy in effect as of Feb. 21, 2004.
Short form: I'm trashing EVERY E-mail that doesn't contain a password in the
subject unless it comes from a "whitelisted" (pre-approved by me) address.
See <http://www.sonic.net/~dakidd/main/contact.html> for full details.

 

[testortool]

I've got Wega 24" and 32" TVs and neither have had any problems since bought
new several years ago.

"oddvark" <dgrdinh@yahoo.com> wrote in message
news:1112905062.471577.158740@l41g2000cwc.googlegroups.com...

Hello,

Have any of you had experience working on the newer 30 in Wegas? Are
they problematic? My dad wants a 30 inch wide screen, preferably flat,
but I've heard lots about problems with the wegas. Are the new ones
any better?

Thanks.

 

[Bob Shuman]

As I recall there were two different classes of Wega TVs. I believe one was
a cheaper version (possibly the F or FV series?) I have had only one
problem with my 5-year old 32" model and that is with the clock. It runs
several minutes fast each month making it basically useless. Seems they did
not take advantage of the stable 60 Hertz AC power current for clocking and
instead have a cheap free running oscillator instead. Given the price of
the set, this seems almost ludicrous.

But, the good news is the picture still seems as bright and sharp as the day
we bought it.

Bob

"testortool" <mbillings@comcast.net> wrote in message
news:115b9r91vhakfed@corp.supernews.com...

I've got Wega 24" and 32" TVs and neither have had any problems since
bought
new several years ago.

"oddvark" <dgrdinh@yahoo.com> wrote in message
news:1112905062.471577.158740@l41g2000cwc.googlegroups.com...

Hello,

Have any of you had experience working on the newer 30 in Wegas? Are
they problematic? My dad wants a 30 inch wide screen, preferably flat,
but I've heard lots about problems with the wegas. Are the new ones
any better?

Thanks.

 

Try this guy. I bought one from him for $4.00 plus $4.45 Priority
shipping.

therepairman@optonline.netREMOVETHIS


Remove the REMOVETHIS PRIOR TO EMAILING

Kristy

On 7 Apr 2005 11:34:08 -0700, "captainvideo462002@yahoo.com"
<captainvideo462002@yahoo.com> wrote:

Mat has them for 3.95 which is a great price, if I could walk right in
and buy it but I can't, and through the mail there is a 25.00 minimum,
and shipping and handling would be 9.95 besides. First, I don't need
25.00 worth of stuff and secondly, I don't mind paying standard
shipping but 9.95 is exhorbitant. This combined with their minimum
takes MAT right out of the equation. Does anyone have a more reasonable
source for these things? I just want to buy ONE little motor!
Thanks, Lenny Stein, Barlen Electronics.

 

[William R. Walsh]

Hi!

You should have Googled it. Sorry, couldn't resist, but the answers are
out there.

The technology used is similar to a lot of desktop computer keyboards.
Little rubber domes push down on a "layered" set of contact points. When the
layers touch, the circuit is completed and the result is sent to the
keyboard controller somewhere in the computer.

There are also other ways of doing this...IBM used capacitive switching in
their model M keyboards from so many years ago. I've also seen foil pads
that were pushed down onto a circuit board to make keypresses.

You can also fine the "dome construction" method as well. This design works
similarly to a remote control where similar pads with a small "spot" of
conductive material is on the bottom. Sometimes this material is integrated
into the dome itself. This is probably the keyboard type you have.

William

 

[Ross Herbert]

On Thu, 7 Apr 2005 16:40:41 -0500, "Bob Shuman"
<reshuman@removethis.lucent.com> wrote:

As I recall there were two different classes of Wega TVs. I believe one was
a cheaper version (possibly the F or FV series?) I have had only one
problem with my 5-year old 32" model and that is with the clock. It runs
several minutes fast each month making it basically useless. Seems they did
not take advantage of the stable 60 Hertz AC power current for clocking

Er, a lot of people actually disconnect power completely from the TV,
especially when going on holidays or for whatever reason. It is a pain
to have to reset the time every time you switch on again so that
method is also next to useless. A battery backed xtal controlled clock
would be best a-la your everday PC. Of course, the added cost would
probably mean it is unlikely to be adopted for analog sets since these
are a dying breed. Hopefully, down the track, digital TV transmissions
will all send the time locked to UTC or some other standard.

This paper covers the problem
http://www.broadcastpapers.com/sigdis/BCA03EvertzRightTime-print.htm

 

[DaveC]

On Thu, 7 Apr 2005 14:20:53 -0700, Don Bruder wrote
(in article <Vuh5e.13692$m31.134896@typhoon.sonic.net&gt:

What brand of machine are we speaking of here, anyway?

Apple Macintosh PowerBook G3.
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
me@privacy.net
This is an invalid return address
Please reply in the news group

 

[Franc Zabkar]

On Wed, 6 Apr 2005 16:47:16 -0500, "Wayne Tiffany"
<wayne.tiffanyRMVJUNK@asi.com> put finger to keyboard and composed:

Hey, cool - post a picture of you with it, please.

WT

http://members.optusnet.com.au/~fzabkar/bunny_holo.gif

Apologies to http://www.easterbunnycostumes.com.

"Franc Zabkar" <fzabkar@optussnet.com.au> wrote in message
news:gif851hd7g0lkdhja68kgecnq14egulvah@4ax.com...
On 5 Apr 2005 18:29:19 -0700, "b" <reverend_rogers@yahoo.com> put
finger to keyboard and composed:

http://www.iwantoneofthose.com/HOLOSC.htm

LOL
wonder if anyone tried to buy that!!!
-Ben

Mine arrived yesterday.


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.

- Franc Zabkar
--
Please remove one 's' from my address when replying by email.

 

[Mark D. Zacharias]

mszaloczy@freemail.hu wrote:

Hi all,
I am repairing a B&O Beogram player. I have repaired a good number of
players but this one is so far from the common cdp building methods
that I have problems with it.
The problem of the player is that it spins up the disc (very fast) but
doesn't read. Play simply doesn't start and the display reads 0000.
Seeing that the cd spins I guess the FOK signal is present. Can
anybody tell me how I can go to some kind of a service mode with the
player? Or, does anybody have the service manual? Any kind of help is
appreciated.
I have read somewhere that this player can very easily have connection
problems at its lower board, and the clock IC gets defect easily. I'll
check these, though I guess it wouldn't do anything without the clock
signal.
I cannot find any test points, that also can be a problem later. I
don't know where the RF, TE and FE can be monitored (though I'm not
there yet anyway).
Thanks,
m127

I have heard that some B&O models suffer from bad feedthrough (solder)
connections on the CD process (servo etc) board. This would be a Philips
board, lots of copper plating visible.


Mark Z.

 

[Asimov]

"sofie" bravely wrote to "All" (07 Apr 05 10:32:29)
--- on the heady topic of "Re: Multi-section cap's for Scott 299B tube amp
restoration"

Just a comment I heard the expert on Antiques Roadshow explain that
the integrity of the internal circuits on old equipment has no bearing
whatsoever on value. The real value is in the esthetic cosmetic appeal
and especially the rarity. If it actually operates is only incidental
and nice to know. So I totally agee that it is okay to replace any
defective electros with modern ones.

A*s*i*m*o*v


so> From: "sofie" <sofie@olypen.com>
so> Xref: aeinews sci.electronics.repair:45208

so> Paul:
so> If you are not a purist in your effort to "restore" this tube amp,
so> INSTEAD of replacing the multi-section electrolytics you can just use
so> "single" axial lead or radial electrolytics.

.... Thomas Edison invented the "Light Emitting Resistor"

 

[Sam Goldwasser]

borgunit2003@yahoo.com writes:

Hi,
I am doing a tune up on an old turntable I have and according to the
service manual I need to make measurements with a VTVM (vacuum-tube
voltmeter). I own a Fluke 111 DVM, is there any reason why this can not
work in place of the VTVM.

No. They didn't have DVMs when that service manual was written!

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

 

[Sam Goldwasser]

"Asimov" <Asimov@-removethis-bbs.juxtaposition.dynip.com> writes:

"sofie" bravely wrote to "All" (07 Apr 05 10:32:29)
--- on the heady topic of "Re: Multi-section cap's for Scott 299B tube amp
restoration"

Just a comment I heard the expert on Antiques Roadshow explain that
the integrity of the internal circuits on old equipment has no bearing
whatsoever on value. The real value is in the esthetic cosmetic appeal
and especially the rarity. If it actually operates is only incidental
and nice to know. So I totally agee that it is okay to replace any
defective electros with modern ones.

Though the purists will stuff them into the old cans.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

A*s*i*m*o*v

so> From: "sofie" <sofie@olypen.com
so> Xref: aeinews sci.electronics.repair:45208

so> Paul:
so> If you are not a purist in your effort to "restore" this tube amp,
so> INSTEAD of replacing the multi-section electrolytics you can just use
so> "single" axial lead or radial electrolytics.

... Thomas Edison invented the "Light Emitting Resistor"

 

[Dave Plowman (News)]

In article <1112961009.118795.261390@l41g2000cwc.googlegroups.com>,
<borgunit2003@yahoo.com> wrote:

I am doing a tune up on an old turntable I have and according to the
service manual I need to make measurements with a VTVM (vacuum-tube
voltmeter). I own a Fluke 111 DVM, is there any reason why this can not
work in place of the VTVM.

No - a DVM will be fine. In the days of standard mechanical meter
voltmeters, the only way to get a high impedance input was a valve -
suitable ss devices didn't exist.

--
*One tequila, two tequila, three tequila, floor.

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

 

[Sam Goldwasser]

borgunit2003@yahoo.com writes:

Thanks,
I appreciate the reply. I think your site inspired me to do most of my
own repairs within the last few years. It is truly a fantastic help for
us aspiring electricians and DIYers.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

 

[E. Rosten]

On Wed, 06 Apr 2005 19:03:41 +0000, DaveC wrote:

Underlying the key mechanisms is a double-sided film with concentric circuit
pads (for each key) on either side of the film. The key cap pushes down a
little inverted cone of what looks like silicone rubber to touch the film.

This isn't a contact switch; the top of the film has just one pad, as does
the bottom of the film; no electrical connection is being made.

Are you sure? Those pads are often conductive (check with a resistance
meter). A common construction is for the conductive pad (often not all
that consuctive) to push down on a pattern of traces like this:

____________________
| | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
| | | | | | | | |
_____|___|___|___|___|

Some keyborads (for instance olver versions of the Microsoft Natural
keyboards (I don't know about new ones)) have 3 sheets of plastic bonded
together. The top and bottom sheet have traces printed on, and the central
sheet has holes, but otherwise keeps the other two sheets apart. The keys
push the two outer sheets together (where there is a hole), making a
contact.

Is this hall effect? I can't see anything on the end of the cone, unless
there's something impregnated in it.

Very unlikely.

What technology is used in this kind of keyboard? With 40-pins going
off-board, I presume all matrix processing is done on the motherboard?

Very likely.

If you're interested, I suggest getting an old keyboard (since you can get
new ones for less than 10UKP, I expect you can get an old one for next to
nothing, and probably for free if you try hard enough) and pulling it
apart to see how it works. Many modern seem to use traces printed on
plastic with rubber domes to act as springs. Some old keyboards (like the
BBC computer) had about 70 individual switches soldered down to a board.


-Ed

--
(You can't go wrong with psycho-rats.) (er258)(@)(eng.cam)(.ac.uk)

/d{def}def/f{/Times findfont s scalefont setfont}d/s{10}d/r{roll}d f 5/m
{moveto}d -1 r 230 350 m 0 1 179{1 index show 88 rotate 4 mul 0 rmoveto}
for /s 15 d f pop 240 420 m 0 1 3 { 4 2 1 r sub -1 r show } for showpage

 

[EL]

Well of course this is a matter of personal preference, but if it was me I'd replace all of them.

Unlike wine, electrolytic caps defintely do *not* improve with age ;^)

Eric Law

"Paul" <satellite65nospam@yahoo.com> wrote in message news:42569874$0$6116$afc38c87@...

Thanks to all who took the time to reply. Unless I find a cheaper
source for replacement multi-cans, I will probably gut the old can(s)
and stuff them with new cap's as Sam suggested. It is a fairly shallow
and crowded chassis, so adding parts underneath would be difficult.

Any comments regarding the need to replace based on the measured ESR
values? If not, I'll probably replace only the dead ones at first, and
see if here is any hum.

On 'lytics that have not seen voltage for many years, I know that I
should bring the voltage up slowly the first time. Should I expect the
ESR to change after the first few charging cycles?

Paul

 

[JMK]

I have had a 32FX65 for five years and no problems whatsoever.

Jan

--
jankro (@) saunalahti (.) fi
Please notice my new address!

"oddvark" <dgrdinh@yahoo.com> wrote in message
news:1112905062.471577.158740@l41g2000cwc.googlegroups.com...

Hello,

Have any of you had experience working on the newer 30 in Wegas? Are
they problematic? My dad wants a 30 inch wide screen, preferably flat,
but I've heard lots about problems with the wegas. Are the new ones
any better?

Thanks.

 

[Wayne Tiffany]

Cool - how real is real here????

WT

"Franc Zabkar" <fzabkar@optussnet.com.au> wrote in message
news:99kb519s5pjcsarvi688har7nsl1e26lkb@4ax.com...

On Wed, 6 Apr 2005 16:47:16 -0500, "Wayne Tiffany"
wayne.tiffanyRMVJUNK@asi.com> put finger to keyboard and composed:

Hey, cool - post a picture of you with it, please.

WT

http://members.optusnet.com.au/~fzabkar/bunny_holo.gif

Apologies to http://www.easterbunnycostumes.com.


"Franc Zabkar" <fzabkar@optussnet.com.au> wrote in message
news:gif851hd7g0lkdhja68kgecnq14egulvah@4ax.com...
On 5 Apr 2005 18:29:19 -0700, "b" <reverend_rogers@yahoo.com> put
finger to keyboard and composed:

http://www.iwantoneofthose.com/HOLOSC.htm

LOL
wonder if anyone tried to buy that!!!
-Ben

Mine arrived yesterday.


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.



- Franc Zabkar
--
Please remove one 's' from my address when replying by email.

 

[Michael Black]

Sam Goldwasser (sam@saul.cis.upenn.edu) writes:

borgunit2003@yahoo.com writes:

Hi,
I am doing a tune up on an old turntable I have and according to the
service manual I need to make measurements with a VTVM (vacuum-tube
voltmeter). I own a Fluke 111 DVM, is there any reason why this can not
work in place of the VTVM.

No. They didn't have DVMs when that service manual was written!

It doesn't even make sense why they'd specify a VTVM, given that turntables

are mechanical devices.

Oh, I suppose it's one of those new-fangled turntables that have electronics
to drive the motor in them, and they specify the VTVM so as to not load
down the voltages when measuring.

Michael