Toshiba TV29C90 problem; Image fades to black...

[Eric R Snow]

On 28 Oct 2005 02:11:55 -0700, lucasjensen@gmail.com wrote:

I have a crazy idea:

1. On my self suppored bicycle trips around the world I want to use a
digital camera.
2. I have faced reality and accepted that most digital cameras use
Li-Ion batteries, which makes them very small and handy.
3. Currently I'm interested in a Sony DSC-T7 which uses a Li-Ion
battery. The battery specs can be found here:
http://www.calcellular.com/np-fe1.html
4. I don't want to carry a regular charger but I want to use either a
regular bike generator (the ones powering for front and rear light on a
bicycle), solar cells or a home-built mini wind mill which can be
mounted on the bicycle and produce electricity during the night.

So the question is:
Is it possible to build my own Li-ion charger if I have a varying power
source such as a wind mill? I know that Li-ion batteries are difficult
to charge and that they may be damaged if treated wrongly. I have seen
in some other threads that companies such as Texas Instruments are
offering special ICs. What about the small motor/generator for such a
mini wind mill application - does anybody have recommendations? Are
there some published circuits on the internet which I could use?

Regards, Lucas Jensen
Lucas,

I have been reading some of the posts here and have a suggestion.
First, I'm not very knowledgeable in electronics so take what I say
with a grain of salt. Anyway, here's what I found when researching
battery chargers and batteries for use in digital cameras. Buy a
camera that can use AA size batteries. Many cameras that do will
accept alakiline batteries, NiMh batteries, and lithium ion batteries.
Buy a charger that will charge NiMH batteries and power this charger
from the bicycle charger. Keep a lithium battery or two in you
backpack as backup. These batteries are light and have a very long
shelf life. If you get in a situation where the Nimh batteries are
dead and the LI ion batteries are dead, then you should be able to buy
batteries to tide you over until the charging situation is fixed.
Since you will have up to 4 choices of batteries to choose from your
power needs are quite flexible. Finally, NiMH batteries are much more
tolerant of bad charging situations. Li polymer and Li ion batteries
can explode or catch fire. Because of this some (maybe all) Li
batteries have a device built in to prevent overheating the battery.
I buy batteries and chargers from Thomas Distributing. This company
was well recommended by more than one person and web site. I have no
interest in this company, just a satisfied customer.
Cheers,
Eric

 

[sofie]

150vdc across the filter cap is exactly what you should expect.... as my
previous reply suggested, you can quickly and easily bridge the first
section right after the rectifier of that old multi-section cap with just
about any thing you have laying around with a rating of at least 150 vdc and
a capacitance of 20 to 60MFD... this is not very critical and will instantly
confirm the diagnosis.... so stop guessing here and get a temporary cap
bridged across the old one so you can go forward with the repair.
More than likely all the sections are bad and can all be bridged (usually
not very critical capacitance values) if you want to leave the old one in
place... in fact, as long as it is not shorted or electrically leaking then
you can leave all the connections in place and just neatly install new,
usually smaller, replacement caps under the chassis.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -


snipped:
"tempus fugit" <toccata@no.spam.ciaccess.com> wrote in message

Thanks for your reply Sofie.

I agree with your diagnosis - this reeks of a bad filter cap. The problem
is
that the filter cap is an old cardboard multisection with no marks of any
kind on it. There are 4 tabs on the bottom, with the twistlocks acting as
grounds (I think). Of those tabs, 1 shows a 300 or so ohm resistance to
one
of the twistlocks. Assuiming that that tab is a cap +, and not a ground,
that cap definitely needs replacing. What I'd like to do is just replace
the
lot, but I have no way of knowing what the values of each of the 4 tabs
are
supposed to be. Would just replacing them all with, say, 22uF caps be OK?

 

[Porky]

Hello tempus. I've been away but so have you. From your last post, more
clues are taking shape as to how to fix your phono. We need to know
what power tube is in it. It will have either 8 pins, (25, 35 or 50L6)
making it an early model, or a later model 9-pin 50C5 or 50EH5. Locate
the pin for the plate, on the 50EH5 or 50C5 that is pin 7, looking at
the bottom of the socket and counting clockwise from the gap. On the
8-pin (octal) tube the plate is on pin 3, clockwise from the notch. The
1st filter cap connects to this pin. It is likely a 40 uF rated for no
less than 150 v. You can use up to 80 uF here and use a high voltage
rating like the 400 v units for safety. The next filter cap connects to
pin 5 or 6 I'm not entirely sure but you can trace the wire back to the
multicap. It should also be a 40 uF (50 - 80 uF will work). For third
cap going to pin 1 or 6 of the 12AX7, a lower value like 22 uF may be
alright. The 4th cap should be 22 uFif it runs to the cathode, pin 1 on
the 9-pin or pin 8 of the octal, or the 12AX7, pin 3 or 8. For these
last 2 caps, 150 v rating is OK.

It appears the selenium rectifier has been bypassed already. There is a
solid state diode doing the job. It is likely black with a silver band
but they do come in other colors, looks like a resistor but with only
one band. Ideally, a resistor is included in series with the diode to
bring the voltage down a little to the level of the original.

The shock you recieved could very likey be due to the filter cap
shorting to ground, and replacing all the caps in the multi-cap can
will likely solve both shock and hum problems. A polarized cord is a
very good idea. A 3-prong cord is even better, with the green wire
going to a solid ground point on the chassis. If you ground the
chassis, locate the death cap, (line to chassis cap @ +/- 0.05 uF), and
clip it out of there to prevent future shocks.

BTW, the tube heater supply is likely fed by a tap on the motor
winding, eliminating the need for a separate tranformer. This ain't
hi-fi. Take good care of that pickup cartridge.

JK

 

[Chris Jones]

jaynews wrote:

I bought an inexpensive GE cordless phone 5.8ghz, model 25839. It has a
nickel cadmium battery pack.

The instructions say it should be charged for 12 hours prior to first use,
but say nothing whatsoever about whether or not it's recommended to leave
the phone in the base when not in use.

Do you recommend leaving it in the base all the time or should I only put
it in the base to recharge after a low battery warning happens?

Thanks,

J.

I think that NiCd batteries are more resistant to trickle charging than
NiMH. So if it uses NiCd then don't worry about it.

Chris

 

[JosephKK]

Steve TR wrote:

I appreciate the advice.

I actually already have 2 of these "drop in" bayonet replacements and
while
they are okay for the "casual user" (lol) I'm quite picky and don't want
to look like the rest of the import kiddies with the funky looking LED
tail lamps only lighting up in small spots.

I'm willing to spend $$$ for this project so I can get a correct look and
it seems a flat panel filling the entire area behind the lense will work
wonderfully. Aside from someone's time, I wouldn' think it would be all
that expensive... You can buy generic blank PCBs and a box of LEDs and
solder away. I just suck at soldering. LOL


"3T39" <rubbishrat@hotmail.com> wrote in message
news:4363edf1$0$23278$db0fefd9@news.zen.co.uk...
Hello, 3T39!
You wrote to Steve TR on Sat, 29 Oct 2005 22:42:18 +0100:

"You can buy off the shelf replacements for the 1157's"

Sorry,
just noticed you already knew this. Dooh!
I didn't read the whole post and jumped to the wrong conclusion.




With best regards, 3T39. E-mail: rubbishrat@hotmail.com



Personally, i would try diffusing the existing replacements by roughening

the surface and placing a thin layer of milky plastic in front of the
LED's. A PCB full of LED's would look like a bunch of dots too.
--
JosephKK

 

[JosephKK]

default wrote:

On Sat, 29 Oct 2005 21:54:52 GMT, Ken Weitzel <kweitzel@shaw.ca
wrote:

I'd strongly urge you to check before you install anything other than
the original incandescents. I'm very sure that most places we can't
change them without "breaking the law"

Take care.

Ken

And, what is the law?

Seems to me I see a lot of trucks with new LED signal/stop lights, and
I can get close enough to see no SAE imprimatur on them.

I have an interest in reducing my motorcycle's current usage - and
making myself more visible. LEDs can do it, but I wonder about the
legality (since the DOT has taken 30+ years to accept that halogen
lights are better than "sealed beams" and) I know LED's can make a
big difference in visibility. - seems to me it is just a matter of
waiting (should I live that long) untill the LED lobbyists pay more
than the incandescent lobbyists. And we, the people, might be able to
choose.

I think the bottom line is safety. LED's can do it better than
incandescents - but not in a cost competive way (if one happens to be
a detroit mogul) so, we have to wait until Detroit allows us this
safety feature . . .

Sealed beams were a great improvement over polished silvered iron
reflectors - in the 30's- - and so the law was passed - - Halogen
lights came along in the 60/70s and could project more usable light
where it was needed and not cause glare to oncomming headlights - so
the Europeans had them and the US had to wait until General Electric
could develop halogen (sealed beam) headlights (that threw more light
up in the air than directly ahead). unitl the 80's

When GE got out of the market - auto lighting was more or less for
safety. But there's sitll the spector of some nanny lobbyist out
there to make us safe (in the corporatetly acceptible way).

"I'm very sure that most places we can't
change them without "breaking the law"

Me too.

Then I see celebrities breaking the law. and president's since Nixon,
and presidents circumventing the Consitution since I was born and I
have to wonder what good is the "rule of law?" It is a matter of what
I can get away with - not what is legal.

So how bad can LED lights be?

----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet
News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World!
120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy
via Encryption =----
This sub-thread got me curious, so i looked it up found 49cfr564. Roughly

it says if it gives equivalent light (including color characteristics) and
is otherwise interchangeable with original it is legal. Thus halogen
lamps, LED's, induction lamps or whatever are OK.
--
JosephKK

 

[JosephKK]

Daniel J. Stern wrote:

On Sat, 29 Oct 2005, frenchy wrote:

How about coming up with some off the shelf or homemade diffuser of
some kind to snap or attach to the end of the 1157 LED bulbs?

The "1157 LED bulbs" don't put out nearly enough total light, period. No
diffuser is going to help that.

And you came up with this how? legal requirements state otherwise.

--
JosephKK

 

[Dana]

Changing the phone volume doesn't usually have an effect on the outgoing
talk, just what you hear.

On Sun, 6 Nov 2005, MJ wrote:

My Panasonic cordless phone KX-TG2553B used to work fine. Now people I call complain
(and I have verified) that the handset mic volume is extremely low. Changing the phone
volume has no effect. Don't know if the handset was dropped -certainly possible though.
Do these mics ever go bad? I took it apart and found nothing obvious. It cost $125 bucks
in '02 and has been a great phone. TIA

 

[jango2]

Electret condensor mic probably, they're so easy to get, i'd buy 4
options just in case parameters don't match. Prolly answered the phone
with wet hands. 1 word of caution when u open the handset up, watch out
for the gooey keypad , they're oh so icky, sweaty and toxic.
Jango

 

[peter]

Eric R Snow wrote:

On 28 Oct 2005 02:11:55 -0700, lucasjensen@gmail.com wrote:


I have a crazy idea:

1. On my self suppored bicycle trips around the world I want to use a
digital camera.
2. I have faced reality and accepted that most digital cameras use
Li-Ion batteries, which makes them very small and handy.
3. Currently I'm interested in a Sony DSC-T7 which uses a Li-Ion
battery. The battery specs can be found here:
http://www.calcellular.com/np-fe1.html
4. I don't want to carry a regular charger but I want to use either a
regular bike generator (the ones powering for front and rear light on a
bicycle), solar cells or a home-built mini wind mill which can be
mounted on the bicycle and produce electricity during the night.

So the question is:
Is it possible to build my own Li-ion charger if I have a varying power
source such as a wind mill? I know that Li-ion batteries are difficult
to charge and that they may be damaged if treated wrongly. I have seen
in some other threads that companies such as Texas Instruments are
offering special ICs. What about the small motor/generator for such a
mini wind mill application - does anybody have recommendations? Are
there some published circuits on the internet which I could use?

Regards, Lucas Jensen

Lucas,
I have been reading some of the posts here and have a suggestion.
First, I'm not very knowledgeable in electronics so take what I say
with a grain of salt. Anyway, here's what I found when researching
battery chargers and batteries for use in digital cameras. Buy a
camera that can use AA size batteries. Many cameras that do will
accept alakiline batteries, NiMh batteries, and lithium ion batteries.
Buy a charger that will charge NiMH batteries and power this charger
from the bicycle charger. Keep a lithium battery or two in you
backpack as backup. These batteries are light and have a very long
shelf life. If you get in a situation where the Nimh batteries are
dead and the LI ion batteries are dead, then you should be able to buy
batteries to tide you over until the charging situation is fixed.
Since you will have up to 4 choices of batteries to choose from your
power needs are quite flexible. Finally, NiMH batteries are much more
tolerant of bad charging situations. Li polymer and Li ion batteries
can explode or catch fire. Because of this some (maybe all) Li
batteries have a device built in to prevent overheating the battery.
I buy batteries and chargers from Thomas Distributing. This company
was well recommended by more than one person and web site. I have no
interest in this company, just a satisfied customer.
Cheers,
Eric
There are a number of Li-ion chargers available that have a 12 volt

input for in-car use. Of course these could be powered from any 12v
source, so you could charge a bullet proof pack of nicads from your
cycle generator, I suggest a simple full wave rectifier charging 2 or 3
cells in series at a time and then power the Li-ion charger from 9 or 10
cells in series. I suggest nicads because they have the best tolerance
to abuse. I know it's a 2 step process, but it's simple and the tricky
bit can be handled by a professionally manufactured gizmo.

 

[Skype_man]

Have two units, dead, no standby FPA led. M # is D50LPW134YX1,
Chassis # ITC 250. Standby mode isn't available, DM3 has no successfull
boot sequence. At plug in, the FPA led won't light as it's supposed to. Push
power on, or use remote, FPA led comes on, & unit tries to come on
three times, the two cooling fans start, & stop right away each time. Code
11, on one unit, code 63, on the other, but they act exactly the same. Lamps
are ok, tested in a working unit. One RCA Tech says bulb, the other says
light engine...I'm really not sure. These units are really like a computer.
There
is so much that has to happen, in order for it to "be ready to come on", I
can't beleive they work at all. I tried DM-2 reboot, no go, then code 9, no
12 volts or 3.3 volts to the light engine, can't find anything bad in the AC
in
power supply board, light engine isn't pulling the B+ lines low, unhooked
the
AVIO connector to the light engine, still no standby. The color wheel isn't
spinning, & it's all part of the light engine. I think it's the power
supply, but
again...not sure. No shorts, open circuits, excess current draw. Ideas???
Somebody MUST know what's common in these units. Nothing on the RCA
B2B site for this chassis. Thanks for your time, Sky.

 

[Michael A. Terrell]

Anthony Fremont wrote:

IBM completely killed off Honeywell and Burroughs with good marketing
skills, not better hardware. The competition lay in salesmanship and
brainwashing, not making better stuff or even trying to be cost
competitive.

IBM killed off Burroughs? What are you talking about? Burroughs
merged with Sperry in 1986 and still operate under their new name,
Unisys.

http://www.unisys.com/about__unisys/history/


--
?

Michael A. Terrell
Central Florida

 

[MJ]

I've found that using a headset circumvents the low volume mic issue, which implicates
the mic itself, in my way of thinking. Anyone know how to get a schematic for a
Panasonic cordless phone on the web? TIA


"MJ" <mj@address.invalid> wrote in message news:YOidnRTdu-gy1-3eRVn-sA@centurytel.net...

I did some internet searching but couldn't find much on Panasonic low volume problems.
I'm going to try plugging in a headset into the handset and see if that bypasses the
problem. A friend has this identical phone which I tried in my base unit and it works
fine - so I know the trouble is with my handset itself. I'd swap out the mic if I knew
where to find a replacement.


"Michael Kennedy" <Mikek400@remthis.comcast.net> wrote in message
news:bZudndmQGptlhe3eRVn-gA@comcast.com...
I have found this to be a common problem with panasonic phones. I don't know the cause
but mine has the same problem as well as my friends's panasonic phone.


"MJ" <mj@address.invalid> wrote in message
news:2_GdnZZQJe7MZ_PeRVn-hA@centurytel.net...
My Panasonic cordless phone KX-TG2553B used to work fine. Now people I call complain
(and I have verified) that the handset mic volume is extremely low. Changing the
phone volume has no effect. Don't know if the handset was dropped -certainly
possible though. Do these mics ever go bad? I took it apart and found nothing
obvious. It cost $125 bucks in '02 and has been a great phone. TIA

 

[Mxsmanic]

Michael A. Terrell writes:

Anthony Fremont wrote:

IBM completely killed off Honeywell and Burroughs with good marketing
skills, not better hardware. The competition lay in salesmanship and
brainwashing, not making better stuff or even trying to be cost
competitive.


IBM killed off Burroughs? What are you talking about? Burroughs
merged with Sperry in 1986 and still operate under their new name,
Unisys.

IBM didn't kill off Honeywell, either. Honeywell bought GE's computer
division, then Bull SA (the French computer company) bought Honewell's
computer division. Today it survives as Bull SA (the unfortunate name
of the company comes from Fredrik Bull, the Norwegian founder of a
company that ultimately evolved to Bull SA today).

--
Transpose mxsmanic and gmail to reach me by e-mail.

 

[Chris Jones]

do_not_spam_me@my-deja.com wrote:

Why do the battery powered clocks in personal computers tend to keep
worse time than quartz watches, even the $1 ones?

The computer batteries measure fine, at least 3.15V.

I thought that the problem was temperature swings in the computers
(25-38C), but a couple of cheapo watches taped inside the computers
kept better time.

Others have already supplied you with plenty of possible reasons why the
existing crystal oscillator might have poor stability.

If you have some time to work on this, you could improve the PC's clock by
overdriving the internal crystal oscillator circuit with your own stable
oscillator. Most PCs would use a 32768Hz crystal. The oscillator circuit
typically used to be made from a CMOS unbuffered logic inverter chip which
you should be able to find the datasheet for, using google. Some PCs
probably have the oscillator built into the chipset instead, but the
circuit is probably the same so you should still be able to overdrive it.

I would expect that one pin of the crystal will be connected to the output
of a logic gate and the other pin of the crystal will be connected to the
input of a logic gate. There may be various resistors or capacitors in
series too. If you can create a stable 32768Hz square wave and feed it to
the input of the logic gate which is connected to one pin of the crystal
then this should override the oscillator with your externally supplied
signal. You will have to keep the signal running even when the computer is
off or otherwise the clock will stop.

You might be able to build yourself a stable crystal oscillator, or you
might prefer to buy one.

A temperature compensated crystal oscillator or an ovenised oscillator
should be accurate enough. There are many commercial suppliers of these.

Chris

 

[tempus fugit]

Thanks again for the replies guys.

Yet more information:

The power tube is a 50L6. The selenium rectifier has been bypasssed by a
single top hat diode (I guess I was looking for a bridge, or at least 2
diodes).

I tried to rewire the power cord, and I'm getting frustrated. I wired it
correctly, so that the hot lead went to the switch. This put 120v on the
chassis, though so I switched it around. Guess what?? Still 120v on the
chassis. This is with the power off. Before I put the new cable in,
switching the plug around took the 120v off the chassis. The weird thing is
that I can't locate any place where either wire is connected to the chassis,
and there doesn't seem to be a death cap.

Sorry about the infrequency of the replies, but I don't get a lot of free
time to work on it.
Thanks


"Porky" <juan_morre@hotmail.com> wrote in message
news:1131732067.940146.266600@g44g2000cwa.googlegroups.com...

Hello tempus. I've been away but so have you. From your last post, more
clues are taking shape as to how to fix your phono. We need to know
what power tube is in it. It will have either 8 pins, (25, 35 or 50L6)
making it an early model, or a later model 9-pin 50C5 or 50EH5. Locate
the pin for the plate, on the 50EH5 or 50C5 that is pin 7, looking at
the bottom of the socket and counting clockwise from the gap. On the
8-pin (octal) tube the plate is on pin 3, clockwise from the notch. The
1st filter cap connects to this pin. It is likely a 40 uF rated for no
less than 150 v. You can use up to 80 uF here and use a high voltage
rating like the 400 v units for safety. The next filter cap connects to
pin 5 or 6 I'm not entirely sure but you can trace the wire back to the
multicap. It should also be a 40 uF (50 - 80 uF will work). For third
cap going to pin 1 or 6 of the 12AX7, a lower value like 22 uF may be
alright. The 4th cap should be 22 uFif it runs to the cathode, pin 1 on
the 9-pin or pin 8 of the octal, or the 12AX7, pin 3 or 8. For these
last 2 caps, 150 v rating is OK.

It appears the selenium rectifier has been bypassed already. There is a
solid state diode doing the job. It is likely black with a silver band
but they do come in other colors, looks like a resistor but with only
one band. Ideally, a resistor is included in series with the diode to
bring the voltage down a little to the level of the original.

The shock you recieved could very likey be due to the filter cap
shorting to ground, and replacing all the caps in the multi-cap can
will likely solve both shock and hum problems. A polarized cord is a
very good idea. A 3-prong cord is even better, with the green wire
going to a solid ground point on the chassis. If you ground the
chassis, locate the death cap, (line to chassis cap @ +/- 0.05 uF), and
clip it out of there to prevent future shocks.

BTW, the tube heater supply is likely fed by a tap on the motor
winding, eliminating the need for a separate tranformer. This ain't
hi-fi. Take good care of that pickup cartridge.

JK

 

When in doubt, use 33uF or so, @450V (22uF is OK for a start. If the
hum reduces but does not go away altogether, then go up). Otherwise,
200uF @20V or so for LV stuff.

Bridge: Voltage in X 1.4142 = voltage out.
Single diode: Voltage in .7071 = voltage out.

Keep that in mind.

Peter Wieck
Wyncote, PA

 

[David Maynard]

Mxsmanic wrote:

Michael A. Terrell writes:


Anthony Fremont wrote:

IBM completely killed off Honeywell and Burroughs with good marketing
skills, not better hardware. The competition lay in salesmanship and
brainwashing, not making better stuff or even trying to be cost
competitive.


IBM killed off Burroughs? What are you talking about? Burroughs
merged with Sperry in 1986 and still operate under their new name,
Unisys.


IBM didn't kill off Honeywell, either. Honeywell bought GE's computer
division, then Bull SA (the French computer company) bought Honewell's
computer division. Today it survives as Bull SA (the unfortunate name
of the company comes from Fredrik Bull, the Norwegian founder of a
company that ultimately evolved to Bull SA today).

Well, that's a lot of Bull

 

[MJ]

Ok, I pulled the mic off the board and it says C10 on it. I'll try the local Shack.



"Michael Kennedy" <Mikek400@remthis.comcast.net> wrote in message
news:JfCdnbaBB9rm--_eRVn-oA@comcast.com...

You could always try radio shack.
"Skype_man" <skype_man@lycos.co.uk> wrote in message
news5idnTnJ0Ml5xezeRVn-tw@rogers.com...
You MAY find a mic that will work, & fit from a
ghetto blaster, or tape recorder. Sky.




"MJ" <mj@address.invalid> wrote in message
news:2_GdnZZQJe7MZ_PeRVn-hA@centurytel.net...
My Panasonic cordless phone KX-TG2553B used to work fine. Now people I call complain
(and I have verified) that the handset mic volume is extremely low. Changing the
phone volume has no effect. Don't know if the handset was dropped -certainly
possible though. Do these mics ever go bad? I took it apart and found nothing
obvious. It cost $125 bucks in '02 and has been a great phone. TIA

 

[w_tom]

David Maynard wrote:

Well, that's a lot of Bull

But they did swallow Honey Well.