Toshiba TV29C90 problem; Image fades to black...

In article <10vdtpqesbomsb6@news.supernews.com>, someone@micro$oft.com
says...
Not long after beginning to use the newest vehicle (a 2004 model) we started
having problems hearing the person using that vehicle. Its signal would
drop from the repeater intermittently. Sometimes this happens for long
periods, and then again the radio will work the next day.

When this is happening I've listened to the output of the radio using a
scanner and the transmission seems normal. Yet at the same time, people in
the other vehicles never hear some of these transmissions that should be
coming from the repeater.
Click to expand...
Not really enough information for a diagnosis, but my first
guess would be that alternator whine or other noise in the
radio's signal may be interfering with the repeater's abilty
to decode subaudible tone or digital squelch. The M1225
seems a little more susceptible to power noise getting into
the transmit audio than some of Mot's other models.
 
Steve:

Things to check:

1. The repeater requires a subaudible private line tone (PL/CTCSS) or
digital private line data word (DPL) for access. If it is corrupted or
distorted, the mobile audio won't pass through the repeater. That is why
to your scanner and ear, the microphone audio sounds ok. The tone if
good should be a sinewave of 500 to 750 Hz deviation, while if it is
DPL, the code word should be fairly clean squareish wave with symmetry,
flat topped with some visable shoulders (rise and fall). Because it is
data, don't expect each cycle to look like the last! The DPL deviation
should be 500 to 750 Hz deviation. By the way, you need a service
monitor or a receiver and scope with DC coupling on the discriminator to
see these waveforms properly.

2. Cheap mobile radios often have poor filtering on the DC power input.
If the alternator or other circuitry (electronic injectors) are imposing
any noise on the DC power into the radio, the CTCSS or DPL might be
getting distorted by whine or noise impulses. Check this first by
turning the engine off, second by powering the radio from a seperate 12V
battery, finally by observing with an oscilloscope the vehicle power line.

3. Cheap mobile radios (yes I said it again) often have microphonic
(sensitive to mechanical vibration) voltage controlled oscillators (part
of frequency synthesizer) which if subjected to mechanical vibration
(that power stroke engine knocking) will distort the CTCSS or DPL. Check
this by removing the radio from it's bracket and setting it on a pillow
while the engine is running.

4. Finally, Yes it could be a voltage problem, check with a voltmeter,
the radio should work at 13.8 volts +/- 20%. But that would be too obvious!

"The RFI-EMI-GUY"




Steve wrote:

I've Googled this problem to death without success, so I'm hoping someone
here will be kind enough to please point me in the right direction.

I work at a small company that uses the UHF Radius M1225 in its Ford
vehicles powered by the Powerstroke diesel.


Not long after beginning to use the newest vehicle (a 2004 model) we started
having problems hearing the person using that vehicle. Its signal would
drop from the repeater intermittently. Sometimes this happens for long
periods, and then again the radio will work the next day.


When this is happening I've listened to the output of the radio using a
scanner and the transmission seems normal. Yet at the same time, people in
the other vehicles never hear some of these transmissions that should be
coming from the repeater.


Of course we suspected the radio. But when we swapped radios, the same
problem still occurred in the 2004 vehicle.


Anyone care to venture a guess, or point me to a forum that might have some
Motorola techs in it?


I'm beginning to wonder if voltage to the radio may be playing a part in
affecting the signal going into the repeater.


BTW, the business that installed the system can't figure it out, so I'm
grasping at straws.



Many TIA!

Steve
Click to expand...
--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"

The Lost Deep Thoughts By: Jack Handey
Before a mad scientist goes mad, there's probably a time
when he's only partially mad. And this is the time when he's
going to throw his best parties.
 
They don't build radios like they used to. I remember testing the heck
out of these things. 12M specs, TIA-603 etc. What in the world happened?
Try to get "real" specs for a cellphone or FRS radio! give it up!

Ol' Duffer wrote:

In article <10vdtpqesbomsb6@news.supernews.com>, someone@micro$oft.com
says...


Not long after beginning to use the newest vehicle (a 2004 model) we started
having problems hearing the person using that vehicle. Its signal would
drop from the repeater intermittently. Sometimes this happens for long
periods, and then again the radio will work the next day.

When this is happening I've listened to the output of the radio using a
scanner and the transmission seems normal. Yet at the same time, people in
the other vehicles never hear some of these transmissions that should be
coming from the repeater.



Not really enough information for a diagnosis, but my first
guess would be that alternator whine or other noise in the
radio's signal may be interfering with the repeater's abilty
to decode subaudible tone or digital squelch. The M1225
seems a little more susceptible to power noise getting into
the transmit audio than some of Mot's other models.
Click to expand...
--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"

The Lost Deep Thoughts By: Jack Handey
Before a mad scientist goes mad, there's probably a time
when he's only partially mad. And this is the time when he's
going to throw his best parties.
 
On Tue, 18 Jan 2005 23:19:46 -0800, Roy Lewallen <w7el@eznec.com>
wrote:

Don Kelly wrote:
-------
Cable lacing was (and is?) common for control wiring in control panels etc.
in the power industry. In that case the signals involved were either 60Hz or
DC and electromechanical relays and meters were used. coupling between
circuits was a non-issue. However, with the advent of solid state devices,
coupling became a problem. . .

Reminds me of a horror story I heard at an EMC short course. There was a
problem with EMI getting in (or out -- I don't recall) of some equipmant
via the 60 Hz power line. So a filter was mounted somewhere in the
middle of the device where there was room, and the 60 Hz power was
routed through it. Went into production, where they neatly bundled and
laced the 60 Hz power leads with a bunch of other wires. The bundle was
routed along the side of the filter as it went by. The power leads broke
out of the bundle to connect to one side of the filter, and the leads on
the other side of the filter rejoined the bundle.

Roy Lewallen, W7EL
Click to expand...
Many low power circuits now use ribbon cables, and in some instances,
if you are not careful about what wire carries what signal, there can
be intermittent cross-talk which can really screw things up. I had 1
case in 10 years where an Engineer had to come over from Germany to
end up building a filter into a ribbon cable that carried a low
frequency pulse. It took him about a week to find the problem because
of its intermittency.

In fact, IIRC, the engineer ended up routing separate wires out of the
ribbon cable to keep the crosstalk out of them. The odd thing about
this case, is out of the hundreds and hundreds of similar machines
with similar circuitry, this was the only unit that had the problem.

It has been my observation that for pc boards and backplanes, ribbon
cable is the way to go, no lacing required. Which leads me to the
question of why automotive companies don't use it in the engine
compartment. It must have to do with the environmental conditions in
there, it isn't *rugged* enough to withstand the heat and abrasion.

Lg
 
Henry Kolesnik wrote:
As of this moment it has run over 26 hours without shutting down.
I've
never seen any evidence that ESR can be an intermittent phenomena.
Can
someone please tell me how intermittent ESR comes about?
Click to expand...

The measured ESR of an electrolytic capacitor changes with
temperature.... usually ESR decreases slightly. If the power supply
circuit is just at the threshold of operating correctly then very
slight changes in the ESR of critical capacitors will certainly affect
how the power supply operates and sometimes it can cause a catastrophic
failure of other components. Cold or cracked solder connections can
also cause similar intermittent symptoms.
The repair suggestion replies you have been getting to your original
posting are your FIRST troubleshooting and testing steps; otherwise we
are all guessing here.
 
"Steve" <someone@micro$oft.com> wrote:

}Not long after beginning to use the newest vehicle (a 2004 model) we started
}having problems hearing the person using that vehicle.

Descibe what antennas are being used; brand, where they're mounted, etc.

Could be a ground plane problem.

Also, does the problem change depending on whether or not the engine
is running?

Stan.
 
On 25 Jan 2005 22:35:20 GMT jurb6006@aol.com (JURB6006) wrote in Message
id: <20050125173520.15979.00000267@mb-m15.aol.com>:

What are my best options here ?
Click to expand...
http://www.individual.net/
Free.

I'd recommend http://www.forteinc.com/main/homepage.php for a newsreader,
if you don't wish to buy the full version, after 30 days it reverts to a
free version which doesn't support kill filtering.

Good luck!
 
Ad,

I've had good luck with the DeoxIT D5 as I mentioned, often lasting 3-5
years between re-cleaning. Of course pots and switches will last for a
shorter period of time in worse environmental conditions, such as smoke,
dust, cooking, etc. At some point the carbon tracks in the pots can
wear through, and then no amount of cleaning will help.

Regards,
Tim


Mad Ad wrote:
Hi Tim, thanks for the reply- there is no problem getting in there, I have
replaced the transformer and output trannies, renewed traces and even added
extra speaker ports on the back thru the years, just it would be nice to
have the pots back working again.

Has switch cleaner got better lately tho? I did try some of that on a couple
of scratchy pots I had 10 years ago, it lasted a short while but the
scratching came back with a vengeance after a while so I deemed it a false
hope and never used any since.

Ad

"Tim Schwartz" <toschwartz@worldnet.att.net> wrote in message
news:41F504F3.5FAA67AD@worldnet.att.net...
MAD,

FIRST: UNPLUG THE AMP WHEN DOING ANY OF THE FOLLOWING!

There is a good chance that the pots will clean up with a decent
cleaning/lube spray. I like Caig Labs DeoxIT (tm) D5, part number
D5S-6. This will require you to open the amp up, as the spray needs to
get into the working part of the pot, the the front shaft bearing. If
the unit is really filthy with dust/dirt on the inside, then consider
blasting it out with compressed air, or careful use of a vacuum cleaner.

The input selector switch may clean up with a spraying as well. In
both cases, use a small amount of spray and work the controls back and
forth many times. DO NOT flood the controls with the stuff! I'm a full
time tech, working on several items a day and a can of this stuff lasts
me at least 6 months, literally hundreds of switches and controls.
DON'T use it on power switches, as it is flammable! Too little is better
than too much. There are many other spray products out there that are
also fine. Read the label!

As to the broken shaft on the input knob, you can usually cut a small
piece of wood to act as a filler for the missing half. If you need to
glue it in, use a glue that can be removed such as rubber cement or
contact cement so that it can be taken apart if needed for service. As
long as you are gentle when turning the know, it can last for years.

Regards,
Tim Schwartz
Bristol Electronics



Mad Ad wrote:

I have an old Marantz PM310 amplifier with all 3 rotary knobs shot, the
volume, balance and the 3 position click switch.

The vol/bal both have the usual 'microphone swung in the wind' sound of
crackling and rustling when you turn them and the 3 position switch has
one
spline of the 2 broken so the knob falls off and the contacts are shot
anyway because you have to fiddle with it to get it to work on both
channels
at once.

Otherwise the amplifier is in fine condition, its has a few bits
resoldered
and renewed over the years but is still giving stirling service as my
main
amp for PC/TV/Music output, except I have to use it via a mixer because
all
the Marantz controls are so bad.

Im guessing that im SOL trying to find replacement controls for it now?
That
3 position switch looks extremely proprietary and the 2 rotaries are
mounted
in a way that using standard vr pots would not work. The shank is metal
and
much thinner than nylon replacents.

Any ideas please anyone? The unit still has years of life in it, its
just id
like to access the controls without it sounding like a force 10 gale in
the
room.

Thanks a lot

Ad
Click to expand...
 
"SansAdresse" <sansadresse@nullepart.xyz> wrote in message
news:3f3gv0dbt7o220hp7e7o4f3q38ln54agvp@4ax.com...

I did buy the powered subwoofer and the crossover (a venerable
Nakamichi model), only to discover that the jumpered connectors on the
back of the Sony integrated amp are an "accessory loop" (pre-volume
control) and not a Pre-out/Main-in pair.

I would expect higher quality reproduction if things are done the
"right way": not just less distortion, but cleaner sounding music. Are
you saying that the difference wouldn't be perceptible?
Click to expand...
I did browse through the diagrams you posted. Adding the connections you
desire is going to be performed in the 'no fun' zone. Try the easy way for
now, and if you are not happy I'll try to give you a more technically
correct answer.

--
N
 
Martin White Wrote:
My father keeps mentioning a place called "Stuarts" in Reading, but as
yet i
haven't had the chance to look them up. Anyone know of them?
Click to expand...
Hi Martin,

Just bought one of these myself, and will probably have a go at fixing
it myself. Firstly, I only have a manual for the D75, so if anyone can
help me with the D83 I would be grateful.

Lots of issues with mine, especially with the cracked and broken clear
selector on the timebase, so I will machine myself a new one out of
clear acrylic. As for the rest. When I've got mine working, I should be
an expert, so I will gladly have a look at yours for the cost of a few
beers!!!

Best regards

Jon


--
jf1452
 
I have SBC, but they have no timeframe when DSL will be put in my rural area.
AOL is only dropping it for dial up customers.
 
wbsearch posted:

<<
I have SBC, but they have no timeframe when DSL will be put in my rural area.
AOL is only dropping it for dial up customers.
There is nothing in the AOL announcement that says they are dropping newsgroups
only for dialup customers. My access is via Comcast cable, and each time I
access one of the boards, I get the AOL service elimination message.

I only retained AOL for so long because their newsgroup access was so easy, but
other aspects of their service that were useful to me have already gone to hell
and this is the last straw. I wouldn't stay with AOL if they changed their
plan.

So in a week or so I will be ready to dump my AOL account and I'm glad to be
rid of them.

As for why are they dumping newsgroups..... I think it has something to do
with a deal they have with google. I'm glad I unloaded my shares in AOL a few
years ago.

Don
 
"Dbowey" <dbowey@aol.com> wrote in message
news:20050126213355.10729.00000255@mb-m29.aol.com...

I only retained AOL for so long because their newsgroup access was so
easy, but
other aspects of their service that were useful to me have already gone to
hell
and this is the last straw. I wouldn't stay with AOL if they changed
their
plan.
Click to expand...
See also news:alt.free.newsservers
--
N
 
Dbowey (dbowey@aol.com) writes:
wbsearch posted:


I have SBC, but they have no timeframe when DSL will be put in my rural area.
AOL is only dropping it for dial up customers.


There is nothing in the AOL announcement that says they are dropping newsgroups
only for dialup customers. My access is via Comcast cable, and each time I
access one of the boards, I get the AOL service elimination message.

I think AOL's words are misleading.
Click to expand...

I read that message to mean that you won't get newsgroups from AOL. But since
some people access the internet through other means (broadband, or a really
cheap ISP that has local dial in but little more), and pay for AOL on top
of that, they are saying that you may not need AOL for newsgroups since
your ISP may supply them.

AOL won't be supplying newsgroups for people with high speed access, but
the high speed access supplier may supply newsgroups.

The bit about dial up is on the level of their line about how you can access
newsgroups with a newsreader. In fact, the newsreader won't help unless
you have access to a newsserver, be it a free one or one you pay for.

In both cases, the wording seems to try to keep AOL's importance high.
You don't need AOL, especially if you are dialing in somewhere else.
But in reality, if you've got internet access somewhere else, the only
reason you need AOL, especially now that the newsgroups are gone, is
for any AOL specific things (such as forums and chat rooms or whatever
they are called and assuming they continue).

But I don't think they want people to know that.

Michael

I only retained AOL for so long because their newsgroup access was so easy, but
other aspects of their service that were useful to me have already gone to hell
and this is the last straw. I wouldn't stay with AOL if they changed their
plan.

So in a week or so I will be ready to dump my AOL account and I'm glad to be
rid of them.

As for why are they dumping newsgroups..... I think it has something to do
with a deal they have with google. I'm glad I unloaded my shares in AOL a few
years ago.

Don
Click to expand...
 
Note that I don't need a full fledged Pe-in/Man-out pair, which must
have "universal" properties (driving a variety of external power amps
for instance.)

I just just need a "loop" after the volume control where I can hook a
high quality active crossover.


On Tue, 25 Jan 2005 12:14:42 -0600, "jakdedert"
<jdedert@bellsouth.net> wrote:

SansAdresse wrote:
The idea is to cleanly separate the frequencies (I am just going by
the textbook!), and to avoid sending to the main speakers the low
frequencies which may drive them into distortion. (Bach's organ music
is played on the system.)

You shouldn't have to worry about distortion in a subwoofer, but I admire
your fortitude. Yes, you are doing it the 'right' way, but certainly you
are doing it the 'hard' way. I'd try NSM's solution first, then if you have
objectionable distortion....
Click to expand...
 
Did you check the HOT for being Shorted.
Check also the regulator and associated components.

kip
"Michele Smith" <michele062@sympatico.ca> wrote in message
news:OE6Kd.8178$mA5.577446@news20.bellglobal.com...
One quick question before I dig into it. It powers up, but there is no
power to the filaments. I've removed and cleaned the L14401 and pads, but
no
go. Any ideas? Thanks. Mark
Click to expand...
 
I've now repaired the motor. Now a problem
related to use. Not familiar with these upright 'hoovers'
and this one was retrieved from being dumped.
I don't know if its something missing or what.
The only way I can keep the swivel base section with
rotary brush in contact
with the floor is to hook a piece of bungee between the
rotary brush housing section and the mains-cable clip on
the handle base. Should this whole section be pivotting
totally freely so torque with the drive belt keeps the base
in contact with the floor or is some spring mechanism
missing ?
 
On Thu, 27 Jan 2005 10:31:39 -0600, "jakdedert"
<jdedert@bellsouth.net> wrote:
If you do not like the results--or you have a lot of time on your hands and
like to experiment--suss out the preamp wiring in your amp and go it the
hard way.
Click to expand...
One part of my question got lost in the discussion: We don't need a
full-fledged Pre-out that can drive a power amplifier, with all that
goes with that.

We only need to *insert* a line level active crossover (a "simple"
filter) on the signal path after (right after?) the volume control.

Can't that be done on the cheap? Just cut the signnal path and insert
two pairs on cinch connectors Out==In.

Are you saying that the difference wouldn't be perceptible?


Not necessarily. I'm just saying that the results may be perfectly
acceptable for the application, by going the route NSM detailed: ie dropping
the speaker sig to an appropriate level for the input of the sub with a
resistor network. This is considerably less work than adding pre outs to
the amplifier and should work quite well. In fact, you could 'kludge up' a
network with just the resistors and a pair of RCA cables connected to the
'B' speaker outs in half an hour or so.


If you have limited experience, you may end up destroying your reciever; in
which case you can then get one which has a sub output or at least a preamp
out.
Click to expand...
 
Unfortunatly that's probably your only option, you've tried just about
everything else, though it wouldn't hurt to leave the cmos battery out for a
bit like you did. You could check for bulging or leaking electrolytic
capacitors on the motherboard but other than that it's probably not
economical to repair unless you can find a working one with a broken screen.
Click to expand...
Some of those have a reset button as I recall. Usually a small hole somewhere on
the bottom with a tact switch inside. Might be worth a look.

Alan Harriman


>
 
Hello Tim!
I have the same problem, do you get any more Information.
Please send me a mail
PLEASE MAIL TO autic@aon.at
Heinz
Austria
 
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