Toshiba TV29C90 problem; Image fades to black...

I previously wrote:
.....
I'd appreciate any suggestions as to what to try, especially related to
the AU-101 in particular.
Click to expand...
In addition, my friend who gave me the amp has confessed that it worked
perfectly until he started using it as a guitar amp .... I suppose that
makes the problem more interesting.

Does this narrow it down any?

Thanks,

Alisdair
 
Hello again,

Thanks to Chuck for suggesting the LM-324 IC being bad, as that was the
problem.

Regards,
Tim Schwartz
Bristol Electronics


Tim Schwartz wrote:
Hello all,

I've got a Thorens TD-180 turntable with a runaway speed condition.
Usually, this is caused by the lamp that shines on the photo cell going
bad, but not here. There are pulses coming out of the photo cell, and
the lamp works.

I've tried contacting both the US distributor to order a shop manual,
and I've e-mailed Thorens in Switzerland to no avail, and its been
months. Does anyone have a schematic that I could get a photocopy of?
Any other suggestions would be welcomed too.

Regards,
Tim Schwartz
Bristol Electronics
Click to expand...
 
On Sun, 14 Sep 2003 14:57:01 +0100, Alisdair
<alisdair@tullo.dont_spam_me.me.uk> wrote:

I previously wrote:
....
I'd appreciate any suggestions as to what to try, especially related to
the AU-101 in particular.

In addition, my friend who gave me the amp has confessed that it worked
perfectly until he started using it as a guitar amp .... I suppose that
makes the problem more interesting.

Does this narrow it down any?
Click to expand...
One possibility is that he pushed it too hard, blew/fried a speaker,
which put too much of a load on one or both channels.

Tom

Thanks,

Alisdair
Click to expand...
 
In article <bk22vk$urb$1@newsg4.svr.pol.co.uk>, Pete Culf wrote:
Hi, > I have a Sony Handycam model CCD-V88E with a cassette stuck halfway in (or
could be halfway out now I think of it) but anyway, I would appreciate some
expert guidance on how to get the cassette out without using a hammer. Is
this a common problem with these things? can anyone help. any advice much
appreciated. > > Thanks, > Pete
Click to expand...
take to a decent camera shop, they will probably extract it for you
w/o fee, _if_ it can be done w/o dis-assembly. at least you will
know the score w/o taking chances or enduring the frustration. --Loren

 
There is no way to tell for sure without testing and observing the tube. If
your pix looks good you likely have a few more years in it. I repair dozens
of these sets a year and the tubes are holding up very well.

Your problem is likely some bad solder connections and/or bad cap in the
vertical output stage. You can be sure that you also have another dozen to
three dozen leaky and high ESR caps in other areas. If you want to fix this
set reliably, you need to do the following:

1) Look over the component side of the boards carefully for spots around
caps that indicate leakage of electrolyte.
2) Look carefully at the pins, particularly the negative side of all
polarized electrolytic caps for black goo from leakage.
3) Look over the solder side of the boards for black corrosion on any
traces and repair.
4) Test all of the electrolytics for ESR and dc leakage
5) Remove and replace any caps that are bad, leaky, or marginal, cleaning
electrolyte leakage from the board thoroughly.
6) Resolder the legs on the remaining caps and smell for a fishy smell and
listen for the sizzle of electrolyte.
7) Replace any suspect caps and resolder all heat producing components.
8) Put it all back together and do a complete set-up.

I will not repair these sets at all anymore unless the customer will pay to
have the entire set rebuilt as above. I have had too may recalls when I
fixed just the vertical circuit and another cap starts to cause trouble a
week or so later. Every one of these sets has at least a dozen, usually
about three dozen bad caps. All of the boards need to be checked.

You can fix the vertical problem by cleaning up the traces and solder and
replace a few caps, but you will have other problems, perhaps more severe
later if you don't fix the rest of the problems waiting to happen.

Leonard Caillouet

"Pinwiz" <pinwiz@eclectic.com> wrote in message
news:pinwiz-21587F.19130614092003@enews.newsguy.com...
I have an 11 yr old 35" Mitsubishi TV (Model CK-3526R) that starts up
with a thin (1/2") horizontal line for about a half hour and then the
picture is fine.

Is this worth fixing or is it likely a picture tube heading south?

Don Olsen
olsendf@comcast.net
Click to expand...
 
On Sun, 14 Sep 2003 19:13:06 -0400, Pinwiz <pinwiz@eclectic.com>
wrote:

I have an 11 yr old 35" Mitsubishi TV (Model CK-3526R) that starts up
with a thin (1/2") horizontal line for about a half hour and then the
picture is fine.

Is this worth fixing or is it likely a picture tube heading south?

Don Olsen
olsendf@comcast.net
Click to expand...
Your tube is fine you have basic vertical problem not tube, get that
tv fixed.

Cheers,

Wizard
 
This is nothing that a new picture tube wouldn't fix...... big $$$$$$
..... it is probably "new television" time.
--
Best Regards,
Daniel Sofie
Electronics Supply & Repair
-----------------------------


"poopman" <myersd27@hotmail.com> wrote in message
news:agr9mv8hsa0vmh37ajlmempcdu3ipks9ss@4ax.com...
> attached is a picture of the problem discribed in my preivos post
 
Note, this is not a binary group, so no picture made it through.
You will have to post it at a binaries group and reference it here.

That being said it is an "M" line Zenith tv set from 1993 through 1995 which
almost guarantees from your symptoms the picture tube is the fault. A
proper diagnosis with the test equipment inside the tv set is still required
to either confirm or deny the crt as the problem.

David

poopman <myersd27@hotmail.com> wrote in message
news:agr9mv8hsa0vmh37ajlmempcdu3ipks9ss@4ax.com...
> attached is a picture of the problem discribed in my preivos post
 
Exactly !
If before the line it was OK then get it fixed
99% bad solder joint.


kip

--
"Watch the return E-Mail addy its false"
"Jason D." <jpero@sympatico.ca> wrote in message
news:3f65005f.22919632@news1.on.sympatico.ca...
On Sun, 14 Sep 2003 19:13:06 -0400, Pinwiz <pinwiz@eclectic.com
wrote:



I have an 11 yr old 35" Mitsubishi TV (Model CK-3526R) that starts up
with a thin (1/2") horizontal line for about a half hour and then the
picture is fine.

Is this worth fixing or is it likely a picture tube heading south?

Don Olsen
olsendf@comcast.net

Your tube is fine you have basic vertical problem not tube, get that
tv fixed.

Cheers,

Wizard
Click to expand...
 
I have an 11 yr old 35" Mitsubishi TV (Model CK-3526R) that starts up
with a thin (1/2") horizontal line for about a half hour and then the
picture is fine.

Is this worth fixing or is it likely a picture tube heading south?
Click to expand...
It's not the tube, but an indication of a vertical sweep problem. In a
Mitsubishi set, you will have to check for two things:

Leaky caps and cold solder joints. - Reinhart
 
"Licensed to Quill" <vintagepen@compuserve.nospam.com> wrote in message
news:bk3cba$7qk$1@ngspool-d02.news.aol.com...
I have an ES4000 shaver and some ES 8000 units all of which use magnetic
induction base-unit chargers

But I do not have a charger to the 4000. SO I tried putting it on the base
for the Linear ES 8000 units and cant understand why it wont work. Surely
magnetic induction is magnetic induction is magnetic induction and the
values of these units cant be all that different?

Does anyone know how I can get the unit to charge or is there some
relationship between the position of the base and the two arms at the top?
(the 4000 is substantially thinner than the 8000) but Panasonic makes the
new charger prohibitively expensive just to see if my units works

What's important is the number of turns in the secondary unit as the
voltage induced may be insuficient to recharge a battery it wasn't designed
Click to expand...
for
Pete
 
Honestly, this is a cheapie, yes?

Just replace it.

Mark Z.


"MJ Zwiers" <m.j.zwiers@zonnet.nl> wrote in message
news:Krc9b.39060$tK5.5031454@zonnet-reader-1...
Hello,

Problem is that the power unit of this dvd player has a blown up IC
(IC902)
but the front of the IC is not readable so i do not know what to replace
it
with.

Has any1 some advice on this ? maybe a service manual would help.

greetings,

Michel
Click to expand...
 
About 70% or so of all Zenith tv's and Citizen tv's made by Zenith
since around 1992 till now have defective picture tubes that cause
either a defective green gun giving you bright green screen or a G1
short causing the power supply to become defective:

http://www.iwaynet.net/~nesda/Zen90.html

either way 70% of them or so have a defective crt and many are only a
couple of years old,I tell the customer that an average tv should last
over 12 years and I give my customers Zenith's phone number and I tell
them to complain to them:

LG ELectronics (Zenith/Goldstar)
Alabama,USA
Ph:1-800-243-0000

I have had at least 100 customers call Zenith and complain about those
garbage crt's.
 
On 15 Sep 2003 19:36:38 GMT, farberbear@aol.com (David Farber) put
finger to keyboard and composed:

There are a couple of transistors, Q701, A1A4M and Q703, N1A4M, which don't register
much of anything on my dvm in the way of a pn-junction. What kind of
transistors are these?
Click to expand...
Both are digital transistors with integrated 10K base resistors.

The A1A4M is a 50V, 100mA, NPN type, while the N1A4M is its PNP
complement.

Each transistor has an F,B,A, or G prefix depending on package style.

Datasheets are available from http://www.freetradezone.com.
Registration is free.


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.
 
Follow-up: The problem went away when I substituted an upper drum from a
similar machine (the one with the audio problem).

Ken

"Ken_B" <ken5229"at"softhome.net> wrote in message
news:vlufli5hhe8fd5@corp.supernews.com...
Hi...

Yes, the color problem happened rather suddenly. One day it was OK, the
next
day a program I taped had the color problem when played back. The color
was
OK when I played it on a different machine. I've done a couple of head
cleanings to no avail.

Thanks.

Ken

"Ivanhoismine" <ivanagen@aol.commensense> wrote in message
news:20030910094516.22044.00000720@mb-m04.aol.com...
I've seen this problem resolved with a good head cleaning but if that
doesn't
work, you may need a new amplifier chip. Did the color anomalies develop
suddenly or over time? If the former is the case, you're probably in for
an
expensive/time consuming repair :)
Click to expand...
 
I think I'd look for power supply problems, especially bad solder
connections and bad small capacitors in the regulated power supply area. The
bias can be adjusted later, assuming it doesn't get really hot. I don't
really think it's related to the shutting down problem.


Mark Z.



"Ross Mac" <macroeng@att.net> wrote in message
news:%zs9b.143502$3o3.10289900@bgtnsc05-news.ops.worldnet.att.net...
Hi Folks,

I have a Pioneer SX 1250 Reciever that is giving me problems. It shuts
down
after about 30 minutes and the right heatsink seems warmer than the left.
I
have the service manual and have run a few tests but thought I might ask
around before I spend the next couple of days fighting this
one......thanks
for any help....Ross
Click to expand...
 
Try the obvious first. What condition is the heat sink compound in? If it's
dried out... replace the grease. Also... make sure the transistors are tight
to the heat sink. Maybe... swap L for R speakers and see if the problem goes
to the other side. Good luck...

Ross Mac wrote:

Hi Folks,

I have a Pioneer SX 1250 Reciever that is giving me problems. It shuts down
after about 30 minutes and the right heatsink seems warmer than the left. I
have the service manual and have run a few tests but thought I might ask
around before I spend the next couple of days fighting this one......thanks
for any help....Ross
Click to expand...
 
Subject: Pioneer SX 1250
From: "Ross Mac" macroeng@att.net
Date: 9/15/03 8:12 PM Eastern Daylight Time
Message-id: <%zs9b.143502$3o3.10289900@bgtnsc05-news.ops.worldnet.att.net

Hi Folks,

I have a Pioneer SX 1250 Reciever that is giving me problems. It shuts down
after about 30 minutes and the right heatsink seems warmer than the left. I
have the service manual and have run a few tests but thought I might ask
around before I spend the next couple of days fighting this one......thanks
for any help....Ross
Click to expand...

If it plays normally otherwise, I'd bet it's a bias problem. The carbon
trimmers they use to set bias are pure garbage, and they'll drift just looking
at them. There might be two adjustments per channel on this model. Flush them
out with a quality cleaner, and see if they set up normally. If so, replace
the pure garbage pots with mere crappy ones (one grade up ;) and re adjust the
bias.


John Del
Wolcott, CT

"Nothing is so opportune for tyrants as a people tired of its liberty."
Alan Keyes

(remove S for email reply)
 
NOTE

It is suggested that the technician reads all the way through and understand
the following procedure for entering/exiting the service adjustment mode;
then proceed with the instructions working with the receiver. When becoming
familiarwith the procedure, the flow chart for service mode may be used as a
quick guide.

Quick entry to service mode

When minor adjustments need to be done to the electronic controls, the
method of entering the service mode without removal of the cabinet back is
as follows using the remote control:


1.. Select SET-UP icon and select CABLE mode.

2.. Select TIMER icon and set SLEEP time for 30 Min.

3.. Press "ACTION" twice to exit menus.

4.. Tune to the channel 124.

5.. Adjust VOLUME to minimum (0).

6.. Press VOL ? (decrease) on receiver. Red "CHK" appears in upper corner.

To toggle between aging and service modes:

While the "CHK" is displayed on the left top corner of the CRT, pressing
"ACTION" and "VOL" UP on the TV simultaneously will toggle between the
modes. Red "CHK" for serviceand yellow "CHK" for aging.

7.. Press POWER on the remote control to display the service adjustment
modes menu, select adjustment by pressing the volume right/left buttons and
channel up/down buttons on the remote and ACTION to enter the adjustment.




Exiting the service mode:

This TV goes out from service mode when it is unplugged or turned OFF. To
exit the service mode, turn the TV OFF from or unplug the TV from A.C

"Gersson" <fortawesome101@yahoo.com> wrote in message
news:e2e023cd.0309151850.2d9b3cfc@posting.google.com...
If anyone has it, it would really help!
Thanks
Gersson
Click to expand...
 
Subject: Re: Sony STR-DE915 transistor id.
From: Franc Zabkar fzabkar@optussnet.com.au
Date: 9/15/2003 2:43 PM Pacific Daylight Time
Message-id: <h5ccmvg52llbd4tglm18biq4velb5al1ub@4ax.com

On 15 Sep 2003 19:36:38 GMT, farberbear@aol.com (David Farber) put
finger to keyboard and composed:

There are a couple of transistors, Q701, A1A4M and Q703, N1A4M, which don't
register
much of anything on my dvm in the way of a pn-junction. What kind of
transistors are these?

Both are digital transistors with integrated 10K base resistors.

The A1A4M is a 50V, 100mA, NPN type, while the N1A4M is its PNP
complement.

Each transistor has an F,B,A, or G prefix depending on package style.

Datasheets are available from http://www.freetradezone.com.
Registration is free.


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.
Click to expand...
Thanks Franc, that explains the dvm readings.


David Farber
David Farber's Service Center
L.A., CA
 
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