Toshiba TV29C90 problem; Image fades to black...

[Geoffrey S. Mendelson]

Major Debacle wrote:

I need an FSL-520-D Japanese style fluorescent lamp. It is unlike an
American style lamp in that it only has one electrode at each end. An
American style lamp flickers and overheats when plugged into this
Japanese style fixture. Does anyone know where I might be able to
procure these FSL-520-D Japanese style fluorescent lamps?

The AC voltage across this Japanese fluorescent fixture when plugged
into a 110-120 American socket is about 600 volts measured with a
standard American multimeter. Just for my own edification, does anyone
know how this kind of fixture differs in its operation from an American
style fluorescent fixture?

It's called an "Instant Start" bulb.

http://en.wikipedia.org/wiki/Fluorescent_lamp

Page down to the starting section or search the page for "instant start".

Here's an example of one, found with a quick web search:

http://www.kwhlighting.com/Merchant2/merchant.mv?Screen=PROD
&Store_Code=kwh&Product_Code=SYL-22403

(sorry for the split link).

You could call them and ask.

Or just take the bulb to any lighting supply company and ask for
an "instant start bulb" that fits.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel gsm@mendelson.com N3OWJ/4X1GM

 

[ps56k]

Jamie wrote:

ps56k wrote:
I have one of those tall halogen lamps with the internal dimmer knob.
It quit working...
Opened up and removed the slender dimmer board.
It has a BT139F triac, torroid, a couple of caps, the pot, etc
Tested a few points on the board - 120 AC - but nothing coming out.

If the traic is bad, what or where can I find a replacement ?

Did a search for BT139F and really didn't find anything besides
datasheets. tnx - Phil


http://www.datasheetcatalog.org/datasheet/philips/BT139F-800G.pdf
there is the data sheet on it..
Test the Gate Voltage to low side of the load and make sure you are
getting a trigger voltage.
Normally, these units short and one or two things. They stay one
at full output meaning both thyristors are shorted or, you'll get an
effective dimming of 50% min with control up to 100%, this would
indicate one of the thyristors are shorted and the other isn't.
Getting nothing at all leads me to believe you may some other
problem.
You stated it has a torroid, I assume that maybe a pulse xformer
for the Gate circuit for isolation. You need to test if a pulse
on the input side( Primary) is actually there.

If the torroid isn't doing this job and then maybe it's a common
mode choke which is needed to remove the noise from the line. In this
case, you may have a DIAC component. This looks like a Diode but its
main purpose is to clamp to a short when input phase reaches a set
level, this clamping normally has a capacitor that generates a pulse
for the gate.
You must dig into it more to know..
Btw, this package you have is a Full Pack , fully insulated plastic..
you can replace it with just about any generic type TRIAC that meets
the Amps, Voltage and Trigger current that is close to the existing
component how ever, I would first dig deeper before assuming the
component to be bad.

And Btw, there is a Repair group you may want to ask those
questions in the future.
sci.electronics.repair

tnx for the info and other group - will followup there -

I'll dig a little more, and yeah... it's a classic choke.
Just had it apart on the living room floor with my VOM,
so I'll snip the wires and take it down to the bench.

 

[ps56k]

Jamie wrote:

ps56k wrote:
I have one of those tall halogen lamps with the internal dimmer knob.
It quit working...
Opened up and removed the slender dimmer board.
It has a BT139F triac, torroid, a couple of caps, the pot, etc
Tested a few points on the board - 120 AC - but nothing coming out.

If the traic is bad, what or where can I find a replacement ?

Did a search for BT139F and really didn't find anything besides
datasheets. tnx - Phil


http://www.datasheetcatalog.org/datasheet/philips/BT139F-800G.pdf
there is the data sheet on it..
Test the Gate Voltage to low side of the load and make sure you are
getting a trigger voltage.
Normally, these units short and one or two things. They stay one
at full output meaning both thyristors are shorted or, you'll get an
effective dimming of 50% min with control up to 100%, this would
indicate one of the thyristors are shorted and the other isn't.
Getting nothing at all leads me to believe you may some other
problem.
You stated it has a torroid, I assume that maybe a pulse xformer
for the Gate circuit for isolation. You need to test if a pulse
on the input side( Primary) is actually there.

If the torroid isn't doing this job and then maybe it's a common
mode choke which is needed to remove the noise from the line. In this
case, you may have a DIAC component. This looks like a Diode but its
main purpose is to clamp to a short when input phase reaches a set
level, this clamping normally has a capacitor that generates a pulse
for the gate.
You must dig into it more to know..
Btw, this package you have is a Full Pack , fully insulated plastic..
you can replace it with just about any generic type TRIAC that meets
the Amps, Voltage and Trigger current that is close to the existing
component how ever, I would first dig deeper before assuming the
component to be bad.

And Btw, there is a Repair group you may want to ask those
questions in the future.
sci.electronics.repair

tnx for the info and other group - will followup there -

I'll dig a little more, and yeah... it's a classic choke.
Just had it apart on the living room floor with my VOM,
so I'll snip the wires and take it down to the bench.

 

[Jim Yanik]

Dennis Lee Bieber <wlfraed@ix.netcom.com> wrote in
news:j6adne9fdrFl_6HVnZ2dnUVZ_s_inZ2d@earthlink.com:

The better chargers actually track both voltage and current... Many
battery types will slowly increase in voltage until some peak point, and
then /drop/ in voltage -- the chargers look for that drop to convert
from forced-charge to float/trickle. (I've also got a charger for my
radio gear that includes a thermocouple that looks for a sudden spike in
battery pack temperature, I believe).

most likely either a thermo-switch or a thermistor,not a thermocouple.

--
Jim Yanik
jyanik
at
kua.net

 

[Arfa Daily]

"2apart" <drubnone@yahoo.com> wrote in message
news:0f3ce5e3-dbf6-4073-8fae-30cfbc9dde7f@m3g2000hsc.googlegroups.com...

I am repairing a Panasonic wireless phone. It has a molded silicon
push pad which contains all the phone's buttons. Behind each 'button'
is a small black deposit which, when the button is pressed, contacts a
pwb land. There is, was, a gel coating on the board. I didn't know
if it was crap from the kitchen or an electrolyte; something that was
supposed to be there. What is it, and where can I purchase the gel...
if indeed it isn' t old food? (Yup, I cleaned it off, and now the
phone buttons don't work at all) Thanks.

I used to repair many tens of cordless phones every month, including
Panasonics, and I have never seen any deposit between the conductive rubber
pads on the keymat, and the PCB contact area, which should be there. OTOH, I
have many times seen a deposit such as you describe, which *shouldn't* be
there. It is usually caused by partial chemical breakdown of the conductive
rubber material. In most cases, it is actually quite hard for external
contamination to get between the keymat and the PCB. Generally, the keymats
and PCB can be recovered by a firm treatment with a cotton bud (Q-Tip)
soaked in electronics grade isopropyl alcohol, but you have to be careful
not to be too aggressive with keypad PCBs, where there are tracks and
contact points layed on by deposition of a conductive paint. You should be
able to test that the contact points and the keymatrix scanning all work, by
bridging individual button locations, with a small piece of aluminium foil.

Arfa

 

[Michael Kennedy]

<fynnashba@yahoo.com> wrote in message
news:6fd0d72b-6f6d-42a7-9ac5-ee23fec4a265@l64g2000hse.googlegroups.com...

I am working on my oldman's HP laserjet 1150 printer 220v. the problem
with this printer is that it has been worked on b4, the power IC kept
blowing (STR Z2012 ). I wonder if this is the correct IC. Pls anyone
with an idea --- help. Thanks.

Check the service manual, you can download it for free.

http://www.eserviceinfo.com/index.php?what=search2&searchstring=Laserjet+1150

Mike

 

[Gareth Magennis]

"Matthew Karam" <mkaram@gmail.com> wrote in message
news:6ef88d83-6121-490e-a4bf-b5cccb4c592a@l28g2000prd.googlegroups.com...

I'm putting a new end on a single phase AC cord for a Japanese
instrument (yes, I have the 100v supply)
The colors are red, black and white.
Which is live and which is ground? Does anybody know?

Thanks,
-Matt

Ground should be connected to the equipment casing. Live should go to the
mains fuse and mains switch.

With the mains switch on, you should be able to read the low resistance
mains transformer primary coil between live and neutral.



Gareth.

 

[Allodoxaphobia]

On Tue, 27 May 2008 23:32:46 GMT, James Sweet wrote:

Major Debacle wrote:

It does not list the wattage, at least not in western characters. There
are some Japanese characters which I do not understand. The only
designation is FSL-520-D, and I believe the '520' refers to the nominal
length in millimeters. I would bet that this tube is hard to find, even
in Japan. I will probably change the electrical guts to accept a
standard two-pin 21 inch tube.

That would be easy enough to do. You can get electronic ballasts now
which are very compact. All you need is a ballast and suitable sockets,
probably easiest to buy a whole fixture.

s/easiest/less expensive/

But, in any case, it'll no doubt be Made In China crap.

Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
*** Killfiling google posts: <http://jonz.net/ng.htm>

 

[Allodoxaphobia]

On Tue, 27 May 2008 23:32:46 GMT, James Sweet wrote:

Major Debacle wrote:

It does not list the wattage, at least not in western characters. There
are some Japanese characters which I do not understand. The only
designation is FSL-520-D, and I believe the '520' refers to the nominal
length in millimeters. I would bet that this tube is hard to find, even
in Japan. I will probably change the electrical guts to accept a
standard two-pin 21 inch tube.

That would be easy enough to do. You can get electronic ballasts now
which are very compact. All you need is a ballast and suitable sockets,
probably easiest to buy a whole fixture.

s/easiest/less expensive/

But, in any case, it'll no doubt be Made In China crap.

Jonesy
--
Marvin L Jones | jonz | W3DHJ | linux
38.24N 104.55W | @ config.com | Jonesy | OS/2
*** Killfiling google posts: <http://jonz.net/ng.htm>

 

[Michael Kennedy]

"jakdedert" <jakdedert@bellsouth.net> wrote in message
news:uv5%j.72313$3v1.35600@bignews3.bellsouth.net...

Matthew Karam wrote:
I did a lot of googling before posting here. If you would let me know
what search criteria you used to find the answer I would be much
obliged.....


On May 27, 7:07 pm, jakdedert <jakded...@bellsouth.net> wrote:
Matthew Karam wrote:
I'm putting a new end on a single phase AC cord for a Japanese
instrument (yes, I have the 100v supply)
The colors are red, black and white.
Which is live and which is ground? Does anybody know?
Thanks,
-Matt
Google knows....

jak

Well, hush my mouth! You're right in that the particular colors you've
encountered, do not fit anybody's standard. The Japanese (now, at least),
use the American standard of Black (hot), White (neutral) and Green
(ground or earth). One reference noted the hot might be Red or Blue
instead of Black; but nothing matches your scheme.

I think the only obvious answer (without a schematic) would be to crack
open that instrument and trace it out. FWIW, the ground will be connected
to the equipment case and the hot will likely be the switched line.

jak

What kind of Japanese equipment has a 3 prong connection on it? They don't
use the same 3 connector NEMA connector we use in America they use the older
2 prong connector that was used in the USA in the 1960's. The only thing I
saw in japan with a ground was a washing machine and it had a seperate wire
that had to be attached to a screw on the outlet.

Mike

 

[Michael Kennedy]

"jakdedert" <jakdedert@bellsouth.net> wrote in message
news:uv5%j.72313$3v1.35600@bignews3.bellsouth.net...

Matthew Karam wrote:
I did a lot of googling before posting here. If you would let me know
what search criteria you used to find the answer I would be much
obliged.....


On May 27, 7:07 pm, jakdedert <jakded...@bellsouth.net> wrote:
Matthew Karam wrote:
I'm putting a new end on a single phase AC cord for a Japanese
instrument (yes, I have the 100v supply)
The colors are red, black and white.
Which is live and which is ground? Does anybody know?
Thanks,
-Matt
Google knows....

jak

Well, hush my mouth! You're right in that the particular colors you've
encountered, do not fit anybody's standard. The Japanese (now, at least),
use the American standard of Black (hot), White (neutral) and Green
(ground or earth). One reference noted the hot might be Red or Blue
instead of Black; but nothing matches your scheme.

I think the only obvious answer (without a schematic) would be to crack
open that instrument and trace it out. FWIW, the ground will be connected
to the equipment case and the hot will likely be the switched line.

jak

What kind of Japanese equipment has a 3 prong connection on it? They don't
use the same 3 connector NEMA connector we use in America they use the older
2 prong connector that was used in the USA in the 1960's. The only thing I
saw in japan with a ground was a washing machine and it had a seperate wire
that had to be attached to a screw on the outlet.

Mike

 

[Michael Kennedy]

"James Sweet" <jamessweet1@trashmail.net> wrote in message
newsRB_j.5674$0R.3256@trndny05...

NoSp wrote:
Jerry G. wrote:

You can also go to a hardware store and buy metal tape, but it must be
surface insulated for safety issues.

I've just purchased a roll of "aluminum tape" at a local hardware store.
Didn't cost much. They had a multimeter at the store and I got to check
that the outer surface is conductive while the inner surface (the sticky
side) doesn't conduct electricity.
Its acrylic glue surface is protected against moisture, UV, heat and
aging and can stand temperatures up to 120 degrees C for short periods of
time.
The store had no idea if it could be used for shielding electronics (I
don't even know if they understood what I meant).

Does that sound like something I can use, or do I need to look for
something which is specifically named "shielding tape" or similar?


That stuff should be fine, give it a go.

It will be fine and should work without it as well.

Mike

 

[Michael Moroney]

David Lesher <wb8foz@panix.com> writes:

phil-news-nospam@ipal.net writes:

| I envy EU houses. If we had regular 240V/30A+ outlets, I'd be able to
| buy a snowblower with real guts. The 120v@15A ones are wimpy.

So put one in.

The issue is not the outlets available in my house [but I sometimes wish
for 3 phase..].

Rather, it's the ready market of consumer appliances that would take
advantage of them. That would require many houses to have them.

Yes the inability to go to the nearest WallyWorld and buy a 240V 4kW
cooker/microwave/whatever is a big problem. European appliance could be
got, but I'd worry about anything with a motor (50 Hz), clock (do their
electronic clocks operate off the line frequency like some in the US?),
microwaves (don't they use frequency-dependent constant voltage
transformers?).

 

[Michael Moroney]

David Lesher <wb8foz@panix.com> writes:

The other "cans" you often see on poles are capacitors used to adjust
the power factor on some secondaries.

Capacitors are in various places but we also have three 7200V line
regulators a block away, one on each primary phase. They are
auto-transformers, with allegedly auto-controlled tap changers, much as
the other poster described. [But his description is more complex than
I recall from the class covering same. The essential aspect was you
CAN short two taps together while switching; the inductance limits the
current change while you do..]

I say "allegedly" as twice now, the regulators have stuck and my UPS
woke me up at 2:30AM with notices it was disconnecting from the now-128v+
line. I solved the issue that night by putting a Variac in the line
ahead of it, and cranking it down.

I also asked about tap changers/regulators. Is this what these are, and
if so, are they likely to be manual or automatic?

http://tinyurl.com/534ffq (Google Maps street view of a set of 3 on a pole
in upstate NY. You may have to click on street view and rotate to see them)

 

In alt.engineering.electrical Michael Moroney <moroney@world.std.spaamtrap.com> wrote:
| David Lesher <wb8foz@panix.com> writes:
|
|>phil-news-nospam@ipal.net writes:
|
|>>| I envy EU houses. If we had regular 240V/30A+ outlets, I'd be able to
|>>| buy a snowblower with real guts. The 120v@15A ones are wimpy.
|
|>>So put one in.
|
|>The issue is not the outlets available in my house [but I sometimes wish
|>for 3 phase..].
|
|>Rather, it's the ready market of consumer appliances that would take
|>advantage of them. That would require many houses to have them.
|
| Yes the inability to go to the nearest WallyWorld and buy a 240V 4kW
| cooker/microwave/whatever is a big problem. European appliance could be
| got, but I'd worry about anything with a motor (50 Hz), clock (do their
| electronic clocks operate off the line frequency like some in the US?),
| microwaves (don't they use frequency-dependent constant voltage
| transformers?).

It's all chicken and egg.

People don't usually go to the added expense of installing a 240V outlet when
there are hardly any (and none at WallyWorld) 240V appliances.

Appliances are not generally made at power levels requiring 240V, at least for
homes, because there is nowhere to plug it in by default.

BTW, one appliance I am interested in is an electric induction wok. Normally
a wok just doesn't work right used over an electric burner surface. So most
wok cooktops are gas based. However, the induction technology with the right
kind of work actually does work fine on electric power. The catch is it needs
a lot of power. Only the smallest version can run on 120V. All the rest need
240V. Here is the smallest 240V version:

http://www.selectappliance.com/exec/ce-product/ck_mwg-2500

And from this, it indicates world plug options for the 240V versions, which
suggests to me the lowest wattage unit isn't marketed outside of 120V parts
of the world (and hence is probably considered a wimpy model intended to at
least work where 240V isn't available).

http://cooktek.com/product_info.php?c=3&s=24&p=12

--
|WARNING: Due to extreme spam, googlegroups.com is blocked. Due to ignorance |
| by the abuse department, bellsouth.net is blocked. If you post to |
| Usenet from these places, find another Usenet provider ASAP. |
| Phil Howard KA9WGN (email for humans: first name in lower case at ipal.net) |

 

[David Lesher]

moroney@world.std.spaamtrap.com (Michael Moroney) writes:

I also asked about tap changers/regulators. Is this what these are, and
if so, are they likely to be manual or automatic?

http://tinyurl.com/534ff> (Google Maps street view of a set of 3 on a pole
in upstate NY. You may have to click on street view and rotate to see them)

Yes. Note the primaries are broken by insulators, and there is no
secondary [240/120] service on the pole. [The lowest run is TV coax, then
neutral above it.]

I've never heard of such as manual regulators so I assume they are
automatic.


It's somewhat unusual to see all three on one pole; it must be a BIG
one. Generally I see them staggered on 3 adjacent poles; or two poles
hold a platform between them.


--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

 

[David Lesher]

moroney@world.std.spaamtrap.com (Michael Moroney) writes:

Rather, it's the ready market of consumer appliances that would take
advantage of them. That would require many houses to have them.

Yes the inability to go to the nearest WallyWorld and buy a 240V 4kW
cooker/microwave/whatever is a big problem. European appliance could be
got, but I'd worry about anything with a motor (50 Hz), clock (do their
electronic clocks operate off the line frequency like some in the US?),
microwaves (don't they use frequency-dependent constant voltage
transformers?).

I don't know if microwave ovens still use ferroresonant transformer
supplies. I'd heard that they'd moved to switchers but have not
worked on any with same. It would make sense: good transformer iron
& copper ain't cheap... and a switcher would also save shipping weight.

And yes, the clock would run fast.

--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

 

[David Lesher]

James Sweet <jamessweet1@trashmail.net> writes:

I've never seen one with a ferro-resonant transformer. They use a
standard laminated core power transformer with a pair of magnetic shunts
to regulate the current.

[Johnny Carson voice] "I did not know that...."

All I've ever had to a u-w power supply was to replace the rectifier
stack; or junk the oven because it was clearly smoked...

Someone one mentioned they were F-R, and a casual look seemed to confirm
that, so I never questioned it. A F-R is also current limited; short the
output and it delivers rated current, period..



--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

 

[Fiat Sparks]

Sam Goldwasser <sam@minus.seas.upenn.edu> wrote:

Never seen an FR uwave. Why would they use that when the basic
circuit is adequate and reliable (more or less!)?

Mostly less! My Panasonic inverter unit just released the magic
smoke. First the magenetron died, and then after I replaced that, an
IGBT in the switcher shorted and did a fair bit of collateral damage.

I finally did find a service manual...in spanish (which I read
poorly,) but it did at least tell me what all the small resistors and
diodes were supposed to be (before they melted.)

So, $100 in parts later, I now have a working microwave again. And, if
I get tired of it, I can sell it on Craigslist for at least $35! :-/

 

[Michael Moroney]

David Lesher <wb8foz@panix.com> writes:

moroney@world.std.spaamtrap.com (Michael Moroney) writes:

I also asked about tap changers/regulators. Is this what these are, and
if so, are they likely to be manual or automatic?

http://tinyurl.com/534ffq> (Google Maps street view of a set of 3 on a pole
in upstate NY. You may have to click on street view and rotate to see them)

Yes. Note the primaries are broken by insulators, and there is no
secondary [240/120] service on the pole. [The lowest run is TV coax, then
neutral above it.]

I've never heard of such as manual regulators so I assume they are
automatic.

Earlier in this thread it was mentioned the automatic ones are expensive
and only used for big substations, not for long runs of distribution
systems like that one. Before I read that I assumed they must be
automatic.

It's somewhat unusual to see all three on one pole; it must be a BIG
one. Generally I see them staggered on 3 adjacent poles; or two poles
hold a platform between them.

At that location there used to be 2 adjacent poles with 3 transformers
on a platform between them, when the downstream was an older delta-
connected system. I bet they just reused one of the heavy duty poles.
I wonder why they simply didn't reuse the platform setup.

I wonder what each of those puppies weigh, and how many MVA they can
handle.