Toshiba TV29C90 problem; Image fades to black...

I've only repaired older VCR's that had idler tire, belt, or those end
of tape sensor problems before (I.E. - easy stuff). I'm not familiar
with the mode switch. Will research.
 
On 10 Oct 2006 13:14:46 -0700, "Wilhelm Duembeg" <wduembeg@gmail.com>
put finger to keyboard and composed:

I got a Fluke 97 Scopemeter, ...

I am looking for the service manual ...
Philips/Fluke no longer sell it. Here's a scan of my own:
http://www.users.on.net/~fzabkar/PM97/

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
So you got what I needed about 7 years ago. Marvelous.

You know what you got there, a piece of technology that isn't made
anymore.

I will splain.

The main 130 volt regulator in that set is the HVOT driver. The
regulation can be so tight that the picture shrinks on high brightness
due to the mass of the electrons. Therefore they have a secondary
regulator. See, in a PTV raster size must stay pretty constant. If not,
convergence would never follow. I mean they had a chart for every
kilovolt that dropped per milliampere.

The main regulator is synced of course, and as it spreads it's on time
to handle the load, and HV is increased pre-emptively. It is a
wonderful system, but a real bitch to work on. They were a bit
self-destructive, with 320 VDC on tap it was not hard to go poof.

Amma tellyas one more thing about the early PTV300s, do not work on
them in a basement, even WITH an isolation transformer. Just don't do
it.

T
 
scott21230@gmail.com wrote:
It eats tapes only sometimes, usually when I stop it. Problem is, that
it doesn't have a rubber idler or any belts. so where should I be
looking.

I'd replace it, but I can't buy one with a digital tuner until next
year and I'd hate to buy a new one only to throw it away early next
year.

A VCR with no idler or belts almost certainly has cheap plastic parts
(gears, etc.) in the drive mechanism, as do most VCRs made today. The
trend is going heavily towards completely gear-driven systems,
eliminating belts and idlers almost entirely; the only problem is, this
type of VCR is or can be extremely noisy--I have a Panasonic VCR which
is very noisy when in rewind, but that's the nature of the system. I
simply use an external rewinder, rather than the VCR's rewind function.
Saves a lot of wear and tear on the VCR's drive mechanism as well.

Your VCR may not be worth repairing unless it is still under
warranty, in which case, of course, I'd go ahead and have it fixed.
But if it's a year or two old or more and out of warranty, I would just
get rid of it and get a new one.

If you get a VCR with an ATSC (digital) tuner next year, you won't
have to discard it early next year or for quite some time. If you have
digital cable you have nothing to worry about as far as compatibility
issues are concerned; your ATSC-equipped VCR will work with the system.
The only drawback is that if you have an analog TV, you won't see the
programs in HD. I have digital cable (with a converter box) and an
analog TV and VCR, and they work just fine together. Yours should as
well; in fact, with a VCR having a digital tuner, as will be required
of all TVs/VCRs next year, you will be able to eliminate your cable box
as well, if you are using one at this time.

Kind regards,

Jeff, WB8NHV (email addy not shown to deter spammers)
Fairport Harbor, Ohio USA
 
- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
Thanks, now time to get in and figure it out... Thanks again.
 
Lenny ...Replace the Thermistor ( just in case ) and put in a SLOW BLOW
fuse.
That will fix it.
kip

<captainvideo462002@yahoo.com> wrote in message
news:1160511526.807156.127870@i3g2000cwc.googlegroups.com...
The 6.3 amp fuse was open. I replaced it with a 4.0 amp just for test
purposes. The degaussing coils happened to be unplugged at the time so
that I could get the chassis out for inspection and the set came on
fine. I then plugged the coils in and tried it. There was a loud hum
from the coils and the fuse lit up and opened. It seems that I recall a
certain series of set that had a problem with the degauss thermistors.
Can't remember if it was Panasonic or someone else's though. I haven't
got a 6.3 amp fuse but I'm pretty sure judging by the way the 4.0 amp
lit up the 6.3 would probably not last either. Is anyone familiar with
this problem who can possibly elaborate on it further? Thanks for any
help. Lenny Stein, Barlen Electronics.
 
Anyone have a link to picture of what this mode switch most likely
looks like? I've never done one before and it might be helpful if I
knew exactly what to look for and if I have to desolder it before
cleaning, etc.
 
John Wrote:
On Mon, 9 Oct 2006 20:10:02 +0100, markkd
markkd.2ffmas@diybanter.com wrote:
-

I wish to replace an old Sunvic room thermostat controlling the coal
fired central heating system. I have purchased a SUNVIC TLX 9201
thermostat. The existing wires are red, yellow, blue & yellow/green.
The new thermostat has 4 connection points.(ie: they are numbered
1,2,3,4) Could someone please guide me as to where these wires should
be placed-cheers!-

How are the terminals on the old thermostat labelled?

How are the terminals defined in the documentation for the new
thermostat?

Some older thermostats actually had words (or at least abbreviations)
to indicate the purpose of each terminal.
Cheers for replying

The instructions for the new thermostat state the following:-

1=common
2=satisfied
3=demand
4=connect to neutral

I am a complete novice when it comes to electrics so any suggestions
that will prevent the house blowing up would be gratefully
received!!!!!!!!




--
markkd
 
<ZZactly@aol.com> wrote in message
news:1160550801.069674.27200@b28g2000cwb.googlegroups.com...
So you got what I needed about 7 years ago. Marvelous.
I got it free about five years ago. Worked pretty good until a "tuning?"
capacitor on the deflection board smoked. Worked another couple of years
and the old white HV transformer died. Bought a set of boards on eBay and
it worked another four months. I have no idea how long my "fix" will last.
You know what you got there, a piece of technology that isn't made
anymore.
Probably for more than one reason... Very few integrated circuits and
discrete components that can be tested and replaced with a little
know-how...
I will splain.

The main 130 volt regulator in that set is the HVOT driver. The
regulation can be so tight that the picture shrinks on high brightness
due to the mass of the electrons. Therefore they have a secondary
regulator. See, in a PTV raster size must stay pretty constant. If not,
convergence would never follow. I mean they had a chart for every
kilovolt that dropped per milliampere.
Magic, eh?
The main regulator is synced of course, and as it spreads it's on time
to handle the load, and HV is increased pre-emptively. It is a
wonderful system, but a real bitch to work on. They were a bit
self-destructive, with 320 VDC on tap it was not hard to go poof.
Yeah, not knowing what some of the zener values are doesn't help much
either...
Amma tellyas one more thing about the early PTV300s, do not work on
them in a basement, even WITH an isolation transformer. Just don't do
it.

I don't trust electricity to follow the rules. As a hobbyist, I unplug the
set first, verify that there is no voltage on the test points and THEN use
clips to hook the meter up. Place the meter on top of the set, verify the
wires are out of the way and then plug it in. The only thing I'm
comfortable testing on live are old digital circuits like Arcade games and
only then on my test bed; not mounted inside the machine with open line
voltage connections.

Like falling off a ladder, you may only get one strike and be out...

Thanks for the info...

Kirk S.
 
scott21230@gmail.com wrote:
Anyone have a link to picture of what this mode switch most likely
looks like? I've never done one before and it might be helpful if I
knew exactly what to look for and if I have to desolder it before
cleaning, etc.

http://www.mainelectronics.com/modeswch.htm
here you are.

note they come in all shapec and sizes.
-B.
 
The instructions for the new thermostat state the following:-

1=common
2=satisfied
3=demand
4=connect to neutral

I am a complete novice when it comes to electrics so any suggestions
that will prevent the house blowing up would be gratefully
received!!!!!!!!
If in doubt you might want to just call an electrician, a thermostat
doesn't take long to install but if you wire it up wrong you could have
a real mess.
 
"markkd" <markkd.2fjbmo@diybanter.com> wrote in message
news:markkd.2fjbmo@diybanter.com...

The instructions for the new thermostat state the following:-

1=common
2=satisfied
3=demand
4=connect to neutral
What voltage is involved? 24 V or 240 V?
 
On 10 Oct 2006 13:24:21 -0700, scott21230@gmail.com put finger to
keyboard and composed:

It eats tapes only sometimes, usually when I stop it. Problem is, that
it doesn't have a rubber idler or any belts. so where should I be
looking.
If your VCR chews tapes when the cassette is ejected, then it could be
that the brake pads need replacing. What normally happens is that the
brakes are applied after the tape is retracted into the cassette
housing. If the brakes slip, then some slack remains outside the
housing and the cassette flap closes over it on the way out.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
BTW Panasonic does have a bulletin regarding nuisance fuse blowing with
appropriate remedies.
"kip" <nospam@nospam.com> wrote in message
news:newscache$vy3z6j$6n8$1@newsfeed.niagara.com...
Lenny ...Replace the Thermistor ( just in case ) and put in a SLOW BLOW
fuse.
That will fix it.
kip

captainvideo462002@yahoo.com> wrote in message
news:1160511526.807156.127870@i3g2000cwc.googlegroups.com...
The 6.3 amp fuse was open. I replaced it with a 4.0 amp just for test
purposes. The degaussing coils happened to be unplugged at the time so
that I could get the chassis out for inspection and the set came on
fine. I then plugged the coils in and tried it. There was a loud hum
from the coils and the fuse lit up and opened. It seems that I recall a
certain series of set that had a problem with the degauss thermistors.
Can't remember if it was Panasonic or someone else's though. I haven't
got a 6.3 amp fuse but I'm pretty sure judging by the way the 4.0 amp
lit up the 6.3 would probably not last either. Is anyone familiar with
this problem who can possibly elaborate on it further? Thanks for any
help. Lenny Stein, Barlen Electronics.
 
Thanks for help, although the 224's cosmetics are a little different
than the 225, the operation is pretty much the same. Thanks again.


--
tech2353
------------------------------------------------------------------------
tech2353's Profile: http://www.futurehardware.in/member.php?userid=133
View this thread: http://www.futurehardware.in/showthread.php?t=233669

Future Hardware - http://www.futurehardware.in
 
I replaced the thermistor with a new one. It checked out resistance
wise cold just like the old one so maybe the old one was good and the
original fuse just stressed. I put in a slow blow fuse and the set
seems to be OK. Thanks for the assistance. Lenny.
Art wrote:
BTW Panasonic does have a bulletin regarding nuisance fuse blowing with
appropriate remedies.
"kip" <nospam@nospam.com> wrote in message
news:newscache$vy3z6j$6n8$1@newsfeed.niagara.com...
Lenny ...Replace the Thermistor ( just in case ) and put in a SLOW BLOW
fuse.
That will fix it.
kip

captainvideo462002@yahoo.com> wrote in message
news:1160511526.807156.127870@i3g2000cwc.googlegroups.com...
The 6.3 amp fuse was open. I replaced it with a 4.0 amp just for test
purposes. The degaussing coils happened to be unplugged at the time so
that I could get the chassis out for inspection and the set came on
fine. I then plugged the coils in and tried it. There was a loud hum
from the coils and the fuse lit up and opened. It seems that I recall a
certain series of set that had a problem with the degauss thermistors.
Can't remember if it was Panasonic or someone else's though. I haven't
got a 6.3 amp fuse but I'm pretty sure judging by the way the 4.0 amp
lit up the 6.3 would probably not last either. Is anyone familiar with
this problem who can possibly elaborate on it further? Thanks for any
help. Lenny Stein, Barlen Electronics.
 

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