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OT: vertical collapse on CRT TV
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J. P. Gilliver (John)
Jan 8, 2013, 11:55:42 PM1/8/13
to
Sorry for off-topic, but thought some here might know some pointers ...
Staying with my blind friends. They have a Panasonic CRT TV, on which
the vertical has collapsed: just a bright line across the middle. I can
see the picture is fine by wobbling my eyeballs vertically.
0: It obviously doesn't matter to them! But I'd like to fix it for me.
(And occasionally so I can do AD for them for non-AD prog.s.)
1: slight emotional attachment (it was her dad's set) prevents
replacement.
2: Also, it has the slightly unusual feature of separate control of main
volume and headphone volume (plugging in 'phones _doesn't_ cut the main
speakers).
The set occasionally does revert to full picture, either of its own
accord for a few seconds or minutes, or after percussive maintenance
(usually just for a moment in that case). So it seems likely it's just a
loose connection, rather than a failed component. But where? The
deflection coils seem to come to a tagstrip centre back top of the tube,
and from (to) there from the main PCB. I've resoldered at the tagstrip,
and where the lead comes from at the PCB. This has usually seemed to
cure the problem, but only for a few minutes (usually just long enough
to convince myself it's working and go through the laborious process of
putting the back back on!).
Does anyone know if this is a common problem with Panasonic sets (it's
relatively modern - square corners, teletext, NICAM, versatile remote
control), and if so, where to look next?
I know it seems pointless (especially as there is indeed a dark line
across the middle of the tube now), but it is irritating to have what
seems such a trivial fault beat me! (Plus points 1 & 2 above against
just replacing it - plus point 0 of course.)
(The set is, obviously, fed from an STB with AD - and speech output too
for that matter, for channel/prog. details etcetera.)
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
…enough cubic zirconia to pebble-dash the Great Wall of China… - Alison
Graham, Radio Times 12-18 February 2011
Staying with my blind friends. They have a Panasonic CRT TV, on which
the vertical has collapsed: just a bright line across the middle. I can
see the picture is fine by wobbling my eyeballs vertically.
0: It obviously doesn't matter to them! But I'd like to fix it for me.
(And occasionally so I can do AD for them for non-AD prog.s.)
1: slight emotional attachment (it was her dad's set) prevents
replacement.
2: Also, it has the slightly unusual feature of separate control of main
volume and headphone volume (plugging in 'phones _doesn't_ cut the main
speakers).
The set occasionally does revert to full picture, either of its own
accord for a few seconds or minutes, or after percussive maintenance
(usually just for a moment in that case). So it seems likely it's just a
loose connection, rather than a failed component. But where? The
deflection coils seem to come to a tagstrip centre back top of the tube,
and from (to) there from the main PCB. I've resoldered at the tagstrip,
and where the lead comes from at the PCB. This has usually seemed to
cure the problem, but only for a few minutes (usually just long enough
to convince myself it's working and go through the laborious process of
putting the back back on!).
Does anyone know if this is a common problem with Panasonic sets (it's
relatively modern - square corners, teletext, NICAM, versatile remote
control), and if so, where to look next?
I know it seems pointless (especially as there is indeed a dark line
across the middle of the tube now), but it is irritating to have what
seems such a trivial fault beat me! (Plus points 1 & 2 above against
just replacing it - plus point 0 of course.)
(The set is, obviously, fed from an STB with AD - and speech output too
for that matter, for channel/prog. details etcetera.)
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
…enough cubic zirconia to pebble-dash the Great Wall of China… - Alison
Graham, Radio Times 12-18 February 2011
Allan Mac
Jan 9, 2013, 3:56:28 AM1/9/13
to
On 9 Jan, 04:55, "J. P. Gilliver (John)" <G6...@soft255.demon.co.uk>
wrote:
PCB with insulated tool to induce/cure fault, 3 blanket resolder that
area, ideally TV on bench, you are looking at screen in a mirror as
you work. Getting connected to any of the H.V. waveforms in a CRT set
is very unpleaseant, death is a possibility !!
Al
wrote:
> Sorry for off-topic, but thought some here might know some pointers ...
>
> Staying with my blind friends. They have a Panasonic CRT TV, on which
> the vertical has collapsed: just a bright line across the middle. I can
> see the picture is fine by wobbling my eyeballs vertically.
>
> 0: It obviously doesn't matter to them! But I'd like to fix it for me.
> (And occasionally so I can do AD for them for non-AD prog.s.)
> 1: slight emotional attachment (it was her dad's set) prevents
> replacement.
> 2: Also, it has the slightly unusual feature of separate control of main
> volume and headphone volume (plugging in 'phones _doesn't_ cut the main
> speakers).
>
> The set occasionally does revert to full picture, either of its own
> accord for a few seconds or minutes, or after percussive maintenance
> (usually just for a moment in that case). So it seems likely it's just a
> loose connection, rather than a failed component. But where? The
> deflection coils seem to come to a tagstrip centre back top of the tube,
> and from (to) there from the main PCB. I've resoldered at the tagstrip,
> and where the lead comes from at the PCB.
Dry joint on PCB in frame output stage. 1, look for obvious, 2 Poke
>
> Staying with my blind friends. They have a Panasonic CRT TV, on which
> the vertical has collapsed: just a bright line across the middle. I can
> see the picture is fine by wobbling my eyeballs vertically.
>
> 0: It obviously doesn't matter to them! But I'd like to fix it for me.
> (And occasionally so I can do AD for them for non-AD prog.s.)
> 1: slight emotional attachment (it was her dad's set) prevents
> replacement.
> 2: Also, it has the slightly unusual feature of separate control of main
> volume and headphone volume (plugging in 'phones _doesn't_ cut the main
> speakers).
>
> The set occasionally does revert to full picture, either of its own
> accord for a few seconds or minutes, or after percussive maintenance
> (usually just for a moment in that case). So it seems likely it's just a
> loose connection, rather than a failed component. But where? The
> deflection coils seem to come to a tagstrip centre back top of the tube,
> and from (to) there from the main PCB. I've resoldered at the tagstrip,
> and where the lead comes from at the PCB.
PCB with insulated tool to induce/cure fault, 3 blanket resolder that
area, ideally TV on bench, you are looking at screen in a mirror as
you work. Getting connected to any of the H.V. waveforms in a CRT set
is very unpleaseant, death is a possibility !!
Al
John Williamson
Jan 9, 2013, 4:30:35 AM1/9/13
to
>> The set occasionally does revert to full picture, either of its own
>> accord for a few seconds or minutes, or after percussive maintenance
>> (usually just for a moment in that case). So it seems likely it's just a
>> loose connection, rather than a failed component. But where? The
>> deflection coils seem to come to a tagstrip centre back top of the tube,
>> and from (to) there from the main PCB. I've resoldered at the tagstrip,
>> and where the lead comes from at the PCB.
>
> Dry joint on PCB in frame output stage. 1, look for obvious, 2 Poke
> PCB with insulated tool to induce/cure fault, 3 blanket resolder that
> area, ideally TV on bench, you are looking at screen in a mirror as
> you work. Getting connected to any of the H.V. waveforms in a CRT set
> is very unpleaseant, death is a possibility !!
>
While you're in there, check all the capacitors and replace as
>> accord for a few seconds or minutes, or after percussive maintenance
>> (usually just for a moment in that case). So it seems likely it's just a
>> loose connection, rather than a failed component. But where? The
>> deflection coils seem to come to a tagstrip centre back top of the tube,
>> and from (to) there from the main PCB. I've resoldered at the tagstrip,
>> and where the lead comes from at the PCB.
>
> Dry joint on PCB in frame output stage. 1, look for obvious, 2 Poke
> PCB with insulated tool to induce/cure fault, 3 blanket resolder that
> area, ideally TV on bench, you are looking at screen in a mirror as
> you work. Getting connected to any of the H.V. waveforms in a CRT set
> is very unpleaseant, death is a possibility !!
>
necessary. They won't be the primary cause of the problem, but some of
them may be suffering from the effects of age, and may fail soon. The
symptoms sound like an intermittent connection on one of the plug/
socket pairs on the board or a dry joint somewhere in the frame driver
stages, possibly on one of the output transistors, which run hot, which
can cause gradual failure of the joints. If you're not confident working
with high voltages, then I'd strongly recommend that you have a word
with your local TV repair shop.
--
Tciao for Now!
John.
charles
Jan 9, 2013, 4:32:31 AM1/9/13
to
In article <al4rlr...@mid.individual.net>, John Williamson
are there any left?
--
From KT24
Using a RISC OS computer running v5.18
--
From KT24
Using a RISC OS computer running v5.18
Brian Gaff
Jan 9, 2013, 4:48:40 AM1/9/13
to
The chances are if this fault has been there for some time the tube itself
is burned at that point which would mean a new set. In modern tvs as it was
in older ones I suppose the faulty part could be almost anywhere in the
field circuit. What you want is someone who knows the actual model, it might
well be common I suppose.
Brian
--
From the Sofa of Brian Gaff Reply address is active
"J. P. Gilliver (John)" <G6...@soft255.demon.co.uk> wrote in message
news:EvnhmaHO...@soft255.demon.co.uk...
> .enough cubic zirconia to pebble-dash the Great Wall of China. - Alison
is burned at that point which would mean a new set. In modern tvs as it was
in older ones I suppose the faulty part could be almost anywhere in the
field circuit. What you want is someone who knows the actual model, it might
well be common I suppose.
Brian
--
From the Sofa of Brian Gaff Reply address is active
"J. P. Gilliver (John)" <G6...@soft255.demon.co.uk> wrote in message
news:EvnhmaHO...@soft255.demon.co.uk...
John Williamson
Jan 9, 2013, 5:05:59 AM1/9/13
to
making a living. Meith's (A small shop with a tiny workshop area) in
Hanley, and the larger Sony/ Panasonic specialists in Tunstall. Both are
willing and able to repair anything I've passed their way so far.
John Williamson
Jan 9, 2013, 5:10:22 AM1/9/13
to
Brian Gaff wrote:
> The chances are if this fault has been there for some time the tube itself
> is burned at that point which would mean a new set. In modern tvs as it was
> in older ones I suppose the faulty part could be almost anywhere in the
> field circuit. What you want is someone who knows the actual model, it might
> well be common I suppose.
> Brian
>
As the owners are reported to be blind, a single darker scan line across
> The chances are if this fault has been there for some time the tube itself
> is burned at that point which would mean a new set. In modern tvs as it was
> in older ones I suppose the faulty part could be almost anywhere in the
> field circuit. What you want is someone who knows the actual model, it might
> well be common I suppose.
> Brian
>
the centre of the restored screen shouldn't be a problem. It probably
wouldn't be that noticeable even for someone with reasonable eyesight,
in the same way that dark pixels on an LCD display are much less
noticeable than bright ones.
Ar
Jan 9, 2013, 5:42:30 AM1/9/13
to
On 09/01/13 10:10, John Williamson wrote:
> As the owners are reported to be blind, a single darker scan line across
> the centre of the restored screen shouldn't be a problem.
Lucky to see it, most modern CRT sets would shut the display down to
> As the owners are reported to be blind, a single darker scan line across
> the centre of the restored screen shouldn't be a problem.
protect the tube from burn-in.
Roderick Stewart
Jan 9, 2013, 7:26:18 AM1/9/13
to
In article <309eba5b-74bd-45f0-8b0b-
including a pair of fairly beefy output transistors that need a heatsink, so
look for something like this close to where the wires from the field coils
connect to the main board. The heatsink may be a separate component made of
frilly aluminium like the ones you can buy in Maplin, or it may be part of a
metal frame structure soldered onto the board to provide some support.
Whatever sort of heatsink it is, the output devices have to be physically
fixed to it, and also soldered to the circuit board, so any flexing can
stress the soldered joints. Get yourself a plastic ruler and a magnifying
glass, and be very careful.
Seriously, you should heed the warnings about high voltages. Doing this sort
of thing can be perfectly safe if you know what to avoid, but very dangerous
if you don't.
Rod.
--
1a60c2...@gu9g2000vbb.googlegroups.com>, Allan Mac wrote:
> > Staying with my blind friends. They have a Panasonic CRT TV, on which
> > the vertical has collapsed: just a bright line across the middle. I can
> > see the picture is fine by wobbling my eyeballs vertically.
[...]
> > Staying with my blind friends. They have a Panasonic CRT TV, on which
> > the vertical has collapsed: just a bright line across the middle. I can
> > see the picture is fine by wobbling my eyeballs vertically.
> > The set occasionally does revert to full picture, either of its own
> > accord for a few seconds or minutes, or after percussive maintenance
> > (usually just for a moment in that case). So it seems likely it's just a
> > loose connection, rather than a failed component. But where? The
> > deflection coils seem to come to a tagstrip centre back top of the tube,
> > and from (to) there from the main PCB. I've resoldered at the tagstrip,
> > and where the lead comes from at the PCB.
>
> Dry joint on PCB in frame output stage. 1, look for obvious, 2 Poke
> PCB with insulated tool to induce/cure fault, 3 blanket resolder that
> area, ideally TV on bench, you are looking at screen in a mirror as
> you work. Getting connected to any of the H.V. waveforms in a CRT set
> is very unpleaseant, death is a possibility !!
CRT field output circuits are very similar to hi-fi amplifiers, typically
> > accord for a few seconds or minutes, or after percussive maintenance
> > (usually just for a moment in that case). So it seems likely it's just a
> > loose connection, rather than a failed component. But where? The
> > deflection coils seem to come to a tagstrip centre back top of the tube,
> > and from (to) there from the main PCB. I've resoldered at the tagstrip,
> > and where the lead comes from at the PCB.
>
> Dry joint on PCB in frame output stage. 1, look for obvious, 2 Poke
> PCB with insulated tool to induce/cure fault, 3 blanket resolder that
> area, ideally TV on bench, you are looking at screen in a mirror as
> you work. Getting connected to any of the H.V. waveforms in a CRT set
> is very unpleaseant, death is a possibility !!
including a pair of fairly beefy output transistors that need a heatsink, so
look for something like this close to where the wires from the field coils
connect to the main board. The heatsink may be a separate component made of
frilly aluminium like the ones you can buy in Maplin, or it may be part of a
metal frame structure soldered onto the board to provide some support.
Whatever sort of heatsink it is, the output devices have to be physically
fixed to it, and also soldered to the circuit board, so any flexing can
stress the soldered joints. Get yourself a plastic ruler and a magnifying
glass, and be very careful.
Seriously, you should heed the warnings about high voltages. Doing this sort
of thing can be perfectly safe if you know what to avoid, but very dangerous
if you don't.
Rod.
--
Brian Gaff
Jan 9, 2013, 11:28:50 AM1/9/13
to
Hmm well yees, but I thought it was for a sighted person to watch at the
same time.
I think he might need a manual.
Brian
--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: bri...@blueyonder.co.uk
______________________________________________________________________________________________________________
"John Williamson" <johnwil...@btinternet.com> wrote in message
news:al4u0e...@mid.individual.net...
same time.
I think he might need a manual.
Brian
--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: bri...@blueyonder.co.uk
______________________________________________________________________________________________________________
"John Williamson" <johnwil...@btinternet.com> wrote in message
news:al4u0e...@mid.individual.net...
Brian Gaff
Jan 9, 2013, 11:31:27 AM1/9/13
to
Yes that bothered me as well, I wonder just how old this device is then?
If its recent, the whole of the field or frame was just a module ic thingy
with aheatsinc. However, earler ones used a large transistor. As has been
said though high voltages do hang around to drive the tube so one needs to
be very careful when tapping and poking.
Brian
--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: bri...@blueyonder.co.uk
______________________________________________________________________________________________________________
"Ar" <A...@127.0.0.1> wrote in message
news:50ed4996$0$7317$5b6a...@news.zen.co.uk...
If its recent, the whole of the field or frame was just a module ic thingy
with aheatsinc. However, earler ones used a large transistor. As has been
said though high voltages do hang around to drive the tube so one needs to
be very careful when tapping and poking.
Brian
--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email: bri...@blueyonder.co.uk
______________________________________________________________________________________________________________
news:50ed4996$0$7317$5b6a...@news.zen.co.uk...
Andy Champ
Jan 9, 2013, 2:53:48 PM1/9/13
to
On 09/01/2013 10:42, Ar wrote:
> Lucky to see it, most modern CRT sets would shut the display down to
> protect the tube from burn-in.
Modern and CRT????
> Lucky to see it, most modern CRT sets would shut the display down to
> protect the tube from burn-in.
This exact fault was the end for my Panasonic. I didn't think it worth
the cost of professional repair, and I'm scared of HT.
Andy
Dave Liquorice
Jan 9, 2013, 3:12:52 PM1/9/13
to
On Wed, 09 Jan 2013 19:53:48 +0000, Andy Champ wrote:
> Modern and CRT????
CRT still knocks spots of many LCD tellies. My Panasonic telly died with
something up with the power supply, mind you this was in 2005 ish and the
set was bought in 1985. It's replacement was another CRT but in 16:9.
As far as delving into the back of CRT tellies, yes there are high
voltages about. Just keep one hand in your pocket or behind you back
don't go diving in with both hands. It's easy to concentrate on keeping
one hand out of trouble but keeping two out of trouble, simultaneously,
is next to impossible.
--
Cheers
Dave.
> Modern and CRT????
CRT still knocks spots of many LCD tellies. My Panasonic telly died with
something up with the power supply, mind you this was in 2005 ish and the
set was bought in 1985. It's replacement was another CRT but in 16:9.
As far as delving into the back of CRT tellies, yes there are high
voltages about. Just keep one hand in your pocket or behind you back
don't go diving in with both hands. It's easy to concentrate on keeping
one hand out of trouble but keeping two out of trouble, simultaneously,
is next to impossible.
--
Cheers
Dave.
NY
Jan 9, 2013, 3:49:29 PM1/9/13
to
"Dave Liquorice" <allsortsn...@howhill.com> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
My Panasonic CRT TV certainly gives a better picture than our LCD TV - Less
chance of burnt-out highlights or colour casts on bright (but not maxed-out)
highlights. On the other hand, I'm really conscious of the flicker on my CRT
TV, having got used to the LCD. Mind you, even better was the picture on my
old (25 years old) 14" JVC TV that I bought cheaply: the Panasonic has a
tendency to render some shades of dark red as a bit plasticky and
artificial.
I'm not afraid of taking the back off things and investigating simple
faults. There are only two things that I won't touch:
- laptop PCs, because getting them apart is an intelligence test and there's
always the worry that I won't be able to get the case back together,
especially if there are hidden springs for the mouse buttons etc
- anything involving voltages higher than mains
I've had a couple of mains shocks though only between fingers on the same
hand and it HURTS! I certainly wouldn't want to risk a hefty shock nowadays
after surviving a heart attack (not electric-shock induced!). I did fit a
headphone jack in the JVC TV yonks ago, but I took the precaution of leaving
the TV unplugged overnight, hoping that the charge in any capacitors would
have leaked away by then. And I only used one hand, just in case...
news:nyyfbegfubjuvyypb...@srv1.howhill.co.uk...
chance of burnt-out highlights or colour casts on bright (but not maxed-out)
highlights. On the other hand, I'm really conscious of the flicker on my CRT
TV, having got used to the LCD. Mind you, even better was the picture on my
old (25 years old) 14" JVC TV that I bought cheaply: the Panasonic has a
tendency to render some shades of dark red as a bit plasticky and
artificial.
I'm not afraid of taking the back off things and investigating simple
faults. There are only two things that I won't touch:
- laptop PCs, because getting them apart is an intelligence test and there's
always the worry that I won't be able to get the case back together,
especially if there are hidden springs for the mouse buttons etc
- anything involving voltages higher than mains
I've had a couple of mains shocks though only between fingers on the same
hand and it HURTS! I certainly wouldn't want to risk a hefty shock nowadays
after surviving a heart attack (not electric-shock induced!). I did fit a
headphone jack in the JVC TV yonks ago, but I took the precaution of leaving
the TV unplugged overnight, hoping that the charge in any capacitors would
have leaked away by then. And I only used one hand, just in case...
Roderick Stewart
Jan 10, 2013, 7:01:09 AM1/10/13
to
In article <ssGdnbh9BIpYRnDN...@brightview.co.uk>, Ny wrote:
> I'm not afraid of taking the back off things and investigating simple
> faults. There are only two things that I won't touch:
>
> - laptop PCs, because getting them apart is an intelligence test and there's
> always the worry that I won't be able to get the case back together,
> especially if there are hidden springs for the mouse buttons etc
I used to think the same way, but I managed to replace the screens of two
> I'm not afraid of taking the back off things and investigating simple
> faults. There are only two things that I won't touch:
>
> - laptop PCs, because getting them apart is an intelligence test and there's
> always the worry that I won't be able to get the case back together,
> especially if there are hidden springs for the mouse buttons etc
damaged laptops that would otherwise have been thrown out, reasoning that I had
nothing to lose but the price of the screen, some of which could probably be
recouped via Ebay if I couldn't get it to work. (There seems to be a market for
incomplete or non-working equipment of every sort, so all would not have been
lost).
I was quite surprised that the first one actually did work, which gave me more
confidence to deal with the second one, which also worked. All it takes is a
bit of time and care. In both cases my first step was to search the net for any
relevant info and found step by step instructions with photos by people who had
done exactly the same thing before with exactly the same models of laptops,
which made it a lot easier. If you have the opportunity to try fixing something
unfamiliar, I'd suggest that it's always worth taking because success will give
you the confidence to deal with the same thing again, and even if it doesn't
work you'll probably have learnt what not to do the next time.
> - anything involving voltages higher than mains
sure before going near them that you know what to avoid, but once again
confidence comes from experience. I will admit that not all my experience with
high voltage has been pleasant, but you will find that this makes the process
of learning what not to do the next time all the more effective. Provided you
survive of course.
Rod.
--
Andy Champ
Jan 10, 2013, 3:23:52 PM1/10/13
to
if the reverse is not true) and anyway by the time I'm pulling it apart
if I can't fix it it's scrap. Though I suppose being in computers since
before there were laptops might help there. Pulling desktops apart for
me is second nature.
On the picture - I've not really noticed any problems with colour on our
new LCD. Compared with the old CRT, however, it's enormously sharper.
Sometime of course this just lets me see the over-compression artefacts
:( Thinking about there was a new item last night where the presenter
looked like Max Headroom, but I presumed that was a camera end problem.
I've had mains across the palm of my hand - I leant on an exposed plug
on some old MOD gear. Not funny.
Andy
michael...@live.co.uk
Jan 10, 2013, 4:51:57 PM1/10/13
to
But might I suggest you pop over to this site:
http://www.vintage-radio.net/forum/index.php
Whilst your telly is not a vintage model, you may find you get a response if you make a sympathetic posting, or at the very least the name of a reputable repairer in your area.
Sorry not to be more helpful, but I've spent too many hours inside the back of tellies to suggest anyone not suitably experienced to go very far. By all means carry out a close visual inspection with the power off to see if you can see anything amiss (dry joint etc). I do mean to seem helpful.
Rick
Jan 10, 2013, 6:35:57 PM1/10/13
to
"J. P. Gilliver (John)" <G6...@soft255.demon.co.uk> wrote in message
news:EvnhmaHO...@soft255.demon.co.uk...
> Sorry for off-topic, but thought some here might know some pointers ...
>
> Staying with my blind friends. They have a Panasonic CRT TV, on which the
> vertical has collapsed: just a bright line across the middle. I can see
> the picture is fine by wobbling my eyeballs vertically.
>
It might be better if you could supply the model number, here's a link to a
>
> Staying with my blind friends. They have a Panasonic CRT TV, on which the
> vertical has collapsed: just a bright line across the middle. I can see
> the picture is fine by wobbling my eyeballs vertically.
>
list of Panasonic stock faults below.
<http://www.highlandelectrix.fsnet.co.uk/tvs/PANASONI.TV.html>
J. P. Gilliver (John)
Jan 11, 2013, 4:06:57 PM1/11/13
to
In message <Oumdnd4nBtHKvnLN...@eclipse.net.uk>, Andy Champ
working; the line across the middle isn't noticeable a lot of the time
(the human brain is clever at such things). I don't know if I'd say
_better_ than a good LCD, but certainly I'm not aware of it being bad.
(As for flicker, I'm one of those who can't tell - at least when looking
at it rather in peripheral vision - between 50 and 60 Hz display; I know
the sensitivity to such varies from person to person.)
By the way - the person who said most modern CRT sets (triggering others
to comment on that combination of words!) shut off to protect the tube
in the event of such a scan collapse: how do they _know_?
would be being scrapped anyway. I recently "fixed" one where the
connection between the DC input socket and the motherboard needed some
touching up, and that was all - but the unit was completely dead until
fixed. (Actually, no: some of the LEDs still came on. Which caused
delay, because it seemed "obvious" that it was still getting power;
presumably it wasn't getting enough!) But my goodness, (a) they put the
fixing screws in the most awkward of places, (b) there are [or were in
that one, anyway] an awful lot of bits that had to be kept [or put back]
in exactly the right places to get the thing back together [what a lot
of little boards; I'd have assumed just one big motherboard, but no way
- little boards for the LEDs, the on switch, some of the USB sockets,
... - all connected together with little cables]. But with care (and, as
someone said, if you can find pictures on the 'net where someone's done
it to the same model, although I didn't in this case), all can be well.
>before there were laptops might help there. Pulling desktops apart for
>me is second nature.
Ditto - though I suspect they'll become a rarity altogether in the not
too distant future (in fact I'd say we're well on the way there already:
the only people who buy desktops, for new machines, are those who want
the last scrap of savings [they're still _slightly_ cheaper], and those
who want very tight control over (or unusual requirements for) what goes
inside, such as gamers.
[]
You can still get it from a disconnected mains plug, if the equipment
has a mains input filter; I've had bites from such, some time after
unplugment.
<no....@nospam.invalid> writes:
>On 09/01/2013 20:49, NY wrote:
[]
>On 09/01/2013 20:49, NY wrote:
>> My Panasonic CRT TV certainly gives a better picture than our LCD TV -
>> Less chance of burnt-out highlights or colour casts on bright (but not
>> maxed-out) highlights. On the other hand, I'm really conscious of the
>> flicker on my CRT TV, having got used to the LCD. Mind you, even better
>> was the picture on my old (25 years old) 14" JVC TV that I bought
>> cheaply: the Panasonic has a tendency to render some shades of dark red
>> as a bit plasticky and artificial.
>>
The set with the field-scan collapse gives a lovely picture when
>> Less chance of burnt-out highlights or colour casts on bright (but not
>> maxed-out) highlights. On the other hand, I'm really conscious of the
>> flicker on my CRT TV, having got used to the LCD. Mind you, even better
>> was the picture on my old (25 years old) 14" JVC TV that I bought
>> cheaply: the Panasonic has a tendency to render some shades of dark red
>> as a bit plasticky and artificial.
>>
working; the line across the middle isn't noticeable a lot of the time
(the human brain is clever at such things). I don't know if I'd say
_better_ than a good LCD, but certainly I'm not aware of it being bad.
(As for flicker, I'm one of those who can't tell - at least when looking
at it rather in peripheral vision - between 50 and 60 Hz display; I know
the sensitivity to such varies from person to person.)
By the way - the person who said most modern CRT sets (triggering others
to comment on that combination of words!) shut off to protect the tube
in the event of such a scan collapse: how do they _know_?
>>
>> I'm not afraid of taking the back off things and investigating simple
>> faults. There are only two things that I won't touch:
>>
>> - laptop PCs, because getting them apart is an intelligence test and
>> there's always the worry that I won't be able to get the case back
>> together, especially if there are hidden springs for the mouse buttons etc
>>
>> - anything involving voltages higher than mains
[]
>> I'm not afraid of taking the back off things and investigating simple
>> faults. There are only two things that I won't touch:
>>
>> - laptop PCs, because getting them apart is an intelligence test and
>> there's always the worry that I won't be able to get the case back
>> together, especially if there are hidden springs for the mouse buttons etc
>>
>> - anything involving voltages higher than mains
[]
>I have no problem with laptops. I reason they are no danger to me (even
>if the reverse is not true) and anyway by the time I'm pulling it apart
>if I can't fix it it's scrap. Though I suppose being in computers since
Yes, I'm similar; as you say, if it gets to that point anyway, they
>if the reverse is not true) and anyway by the time I'm pulling it apart
>if I can't fix it it's scrap. Though I suppose being in computers since
would be being scrapped anyway. I recently "fixed" one where the
connection between the DC input socket and the motherboard needed some
touching up, and that was all - but the unit was completely dead until
fixed. (Actually, no: some of the LEDs still came on. Which caused
delay, because it seemed "obvious" that it was still getting power;
presumably it wasn't getting enough!) But my goodness, (a) they put the
fixing screws in the most awkward of places, (b) there are [or were in
that one, anyway] an awful lot of bits that had to be kept [or put back]
in exactly the right places to get the thing back together [what a lot
of little boards; I'd have assumed just one big motherboard, but no way
- little boards for the LEDs, the on switch, some of the USB sockets,
... - all connected together with little cables]. But with care (and, as
someone said, if you can find pictures on the 'net where someone's done
it to the same model, although I didn't in this case), all can be well.
>before there were laptops might help there. Pulling desktops apart for
>me is second nature.
too distant future (in fact I'd say we're well on the way there already:
the only people who buy desktops, for new machines, are those who want
the last scrap of savings [they're still _slightly_ cheaper], and those
who want very tight control over (or unusual requirements for) what goes
inside, such as gamers.
[]
>I've had mains across the palm of my hand - I leant on an exposed plug
>on some old MOD gear. Not funny.
[]
>on some old MOD gear. Not funny.
You can still get it from a disconnected mains plug, if the equipment
has a mains input filter; I've had bites from such, some time after
unplugment.
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
Can a blue man sing the whites?
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
J. P. Gilliver (John)
Jan 11, 2013, 4:25:19 PM1/11/13
to
In message <628a6aa2-2a72-4f8a...@googlegroups.com>,
michael...@live.co.uk writes:
[]
I don't think we'd pay to have it repaired, for reasons as below.
>
>Sorry not to be more helpful, but I've spent too many hours inside the
>back of tellies to suggest anyone not suitably experienced to go very
>far. By all means carry out a close visual inspection with the power
>off to see if you can see anything amiss (dry joint etc). I do mean to
>seem helpful.
And I don't take it any other way. Although not exactly experienced with
tellies, I've been around electronics - including the odd telly - for a
while. (What gives me more concern than most modern transistorised
tellies - though I am careful there - is old valved radio sets,
especially if [as most were/are!] a half-live chassis.)
Your mention of close visual examination reminds me of the neighbour's
set I looked at quite a few years ago: I can't remember what the fault
was, but anyway, I was on the point of giving up and going away - I
think it was when I switched off the room lights to leave that I noticed
intermittent light from a point on the PCB. On closer examination, it
was a pin where the solder joint - which appeared to be a perfect proper
cone - had cracked in a cylindrical manner; what I'd seen was
intermittent arcing. Repairing that restored the set.
Anyway, re the set with the subject fault: it is here, in the home of my
blind friends whom I visit twice a year. Obviously it doesn't matter to
them; it only matters if I want to watch something with them, and they
"watch" very little TV, as do I when I'm here: we have enough other
things to do when I'm here that they normally can't do [as easily,
anyway] on their own (visiting friends who live in remote places,
certain kinds of shopping, etcetera). Last night I watched with one of
them the third part of the thing about polar bears (which was well AD,
incidentally), and (a) the set worked well for a lot of the time (b) I
_think_ I have convinced myself that I've found a point on the set where
pressure cures the fault and removing such pressure restores it; such is
obviously well on the way to actually finding the loose connection.
However, I'm not (and they suggested that I don't, as we have other
things that need doing) going to attempt to fix it this visit; I _might_
try to remember to turn down the brightness before I go, though I don't
think it matters - the line is burnt into the tube anyway, and I can't
_think_ of any harm it can do to the set to continue to use it with the
fault until I next come here - can anyone?
But thanks to all for all the suggestions and input: all filed for
future reference.
michael...@live.co.uk writes:
[]
>You're thinking along the right lines with a dry joint somewhere on the
>main pcb. Having been fixing tellies for 30 years before retiring last
>year, I'm not going to give you any pointers on where to delve inside
>(apart from not knowing the model no etc).
>
>But might I suggest you pop over to this site:
>
>http://www.vintage-radio.net/forum/index.php
>
>Whilst your telly is not a vintage model, you may find you get a
>response if you make a sympathetic posting, or at the very least the
>name of a reputable repairer in your area.
Thanks for the pointer.
>main pcb. Having been fixing tellies for 30 years before retiring last
>year, I'm not going to give you any pointers on where to delve inside
>(apart from not knowing the model no etc).
>
>But might I suggest you pop over to this site:
>
>http://www.vintage-radio.net/forum/index.php
>
>Whilst your telly is not a vintage model, you may find you get a
>response if you make a sympathetic posting, or at the very least the
>name of a reputable repairer in your area.
I don't think we'd pay to have it repaired, for reasons as below.
>
>Sorry not to be more helpful, but I've spent too many hours inside the
>back of tellies to suggest anyone not suitably experienced to go very
>far. By all means carry out a close visual inspection with the power
>off to see if you can see anything amiss (dry joint etc). I do mean to
>seem helpful.
tellies, I've been around electronics - including the odd telly - for a
while. (What gives me more concern than most modern transistorised
tellies - though I am careful there - is old valved radio sets,
especially if [as most were/are!] a half-live chassis.)
Your mention of close visual examination reminds me of the neighbour's
set I looked at quite a few years ago: I can't remember what the fault
was, but anyway, I was on the point of giving up and going away - I
think it was when I switched off the room lights to leave that I noticed
intermittent light from a point on the PCB. On closer examination, it
was a pin where the solder joint - which appeared to be a perfect proper
cone - had cracked in a cylindrical manner; what I'd seen was
intermittent arcing. Repairing that restored the set.
Anyway, re the set with the subject fault: it is here, in the home of my
blind friends whom I visit twice a year. Obviously it doesn't matter to
them; it only matters if I want to watch something with them, and they
"watch" very little TV, as do I when I'm here: we have enough other
things to do when I'm here that they normally can't do [as easily,
anyway] on their own (visiting friends who live in remote places,
certain kinds of shopping, etcetera). Last night I watched with one of
them the third part of the thing about polar bears (which was well AD,
incidentally), and (a) the set worked well for a lot of the time (b) I
_think_ I have convinced myself that I've found a point on the set where
pressure cures the fault and removing such pressure restores it; such is
obviously well on the way to actually finding the loose connection.
However, I'm not (and they suggested that I don't, as we have other
things that need doing) going to attempt to fix it this visit; I _might_
try to remember to turn down the brightness before I go, though I don't
think it matters - the line is burnt into the tube anyway, and I can't
_think_ of any harm it can do to the set to continue to use it with the
fault until I next come here - can anyone?
But thanks to all for all the suggestions and input: all filed for
future reference.
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
J. P. Gilliver (John)
Jan 11, 2013, 4:32:48 PM1/11/13
to
still have the set (i. e. haven't replaced it - as I mentioned
elsewhere, there is slight attachment to it as it was her late father's
set, and also it has the unusual separate control for headphone and
speaker volume, with the headphone insertion _not_ cutting off the
speakers), and it still has the fault, next time I visit, then further
work will be called for, for which the above link could well be useful
(and I will look at the model number).
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
Dave Liquorice
Jan 11, 2013, 7:32:02 PM1/11/13
to
On Fri, 11 Jan 2013 21:06:57 +0000, J. P. Gilliver (John) wrote:
> By the way - the person who said most modern CRT sets (triggering
> others to comment on that combination of words!) shut off to protect
> the tube in the event of such a scan collapse: how do they _know_?
Well I don't *know* but if you integrate the frame scan waveform and if
> By the way - the person who said most modern CRT sets (triggering
> others to comment on that combination of words!) shut off to protect
> the tube in the event of such a scan collapse: how do they _know_?
it falls below a certain level assume the scans have collapsed.
--
Cheers
Dave.
Roderick Stewart
Jan 12, 2013, 6:23:57 AM1/12/13
to
In article <nyyfbegfubjuvyypb...@srv1.howhill.co.uk>, Dave
a time we used to work with this stuff every day and we've seen the
circuit diagrams.
Rod.
--
Liquorice wrote:
> > By the way - the person who said most modern CRT sets (triggering
> > others to comment on that combination of words!) shut off to protect
> > the tube in the event of such a scan collapse: how do they _know_?
>
> Well I don't *know* but if you integrate the frame scan waveform and if
> it falls below a certain level assume the scans have collapsed.
We know what circuitry most CRT monitors and TVs contain because once upon
> > By the way - the person who said most modern CRT sets (triggering
> > others to comment on that combination of words!) shut off to protect
> > the tube in the event of such a scan collapse: how do they _know_?
>
> Well I don't *know* but if you integrate the frame scan waveform and if
> it falls below a certain level assume the scans have collapsed.
a time we used to work with this stuff every day and we've seen the
circuit diagrams.
Rod.
--
J. P. Gilliver (John)
Jan 13, 2013, 2:54:40 AM1/13/13
to
In message <VA.00000e5...@escapetime.removethisbit.myzen.co.uk>,
I didn't mean the people don't know; I meant how would the circuitry
"know" (that there was/is a fault). RS has supplied a possible mechanism
- though that assumes the circuitry generating the scan waveform has
failed, and his method would indeed detect such a problem; I'm pretty
sure that, on the set in question, the scan's being generated OK, just
not getting to the scan coils - monitoring for _that_ would need
physically separate wiring (like the sense wires on a bench power
supply), and I doubt that that is ever done.
"know" (that there was/is a fault). RS has supplied a possible mechanism
- though that assumes the circuitry generating the scan waveform has
failed, and his method would indeed detect such a problem; I'm pretty
sure that, on the set in question, the scan's being generated OK, just
not getting to the scan coils - monitoring for _that_ would need
physically separate wiring (like the sense wires on a bench power
supply), and I doubt that that is ever done.
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
782.55 - The Number of The Beast (including VAT)
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
Brian
Jan 13, 2013, 7:31:26 AM1/13/13
to
On Sun, 13 Jan 2013 07:54:40 +0000, "J. P. Gilliver (John)"
<G6...@soft255.demon.co.uk> wrote:
<snip>
>I didn't mean the people don't know; I meant how would the circuitry
>"know" (that there was/is a fault). RS has supplied a possible mechanism
>- though that assumes the circuitry generating the scan waveform has
>failed, and his method would indeed detect such a problem; I'm pretty
>sure that, on the set in question, the scan's being generated OK, just
>not getting to the scan coils - monitoring for _that_ would need
>physically separate wiring (like the sense wires on a bench power
>supply), and I doubt that that is ever done.
What you want to verify is that there is current flowing through the
scan coils, since this is what produces deflection.
You can have as large a waveform as you like across the coils but this
will avail you of nought if the fault is that the coils are o/c.
You design a small value resistor in series with the earthy end of the
feed to the coils. Mr Ohm says that a voltage will be developed across
this, whose value and form depends on the scan current. A very small
amount of additional electronics is required to compare this to a
reference and if there isn't enough of it, switch the beams off.
HTH, HAND.
Brian
<G6...@soft255.demon.co.uk> wrote:
<snip>
>I didn't mean the people don't know; I meant how would the circuitry
>"know" (that there was/is a fault). RS has supplied a possible mechanism
>- though that assumes the circuitry generating the scan waveform has
>failed, and his method would indeed detect such a problem; I'm pretty
>sure that, on the set in question, the scan's being generated OK, just
>not getting to the scan coils - monitoring for _that_ would need
>physically separate wiring (like the sense wires on a bench power
>supply), and I doubt that that is ever done.
scan coils, since this is what produces deflection.
You can have as large a waveform as you like across the coils but this
will avail you of nought if the fault is that the coils are o/c.
You design a small value resistor in series with the earthy end of the
feed to the coils. Mr Ohm says that a voltage will be developed across
this, whose value and form depends on the scan current. A very small
amount of additional electronics is required to compare this to a
reference and if there isn't enough of it, switch the beams off.
HTH, HAND.
Brian
Roderick Stewart
Jan 13, 2013, 7:48:18 AM1/13/13
to
In article <upDLnz5A...@soft255.demon.co.uk>, J. P. Gilliver (John)
scan coils, so no "sense wires" coming back from the coils themselves, just a
circuit on the main board to detect the presence of scan current, or at least
the drive voltage. I suppose with some circuit designs it might be possible
for a break in one of those wires to cause scan collapse without the circuit
detecting it, but this is far less likely than a component failure on the
board itself, or mechanical stress on a soldered joint where a large
component also needs to be fixed mechanically to something else, such as a
heatsink. Anything that works can fail of course, but usually the safety
circuits catch the most dangerous or the most likely things.
Rod.
--
wrote:
> >> > By the way - the person who said most modern CRT sets (triggering
> >> > others to comment on that combination of words!) shut off to protect
> >> > the tube in the event of such a scan collapse: how do they _know_?
> >>
> >> Well I don't *know* but if you integrate the frame scan waveform and if
> >> it falls below a certain level assume the scans have collapsed.
> >
> >We know what circuitry most CRT monitors and TVs contain because once upon
> >a time we used to work with this stuff every day and we've seen the
> >circuit diagrams.
> >
> >Rod.
> >--
> >
> I didn't mean the people don't know; I meant how would the circuitry
> "know" (that there was/is a fault). RS has supplied a possible mechanism
> - though that assumes the circuitry generating the scan waveform has
> failed, and his method would indeed detect such a problem; I'm pretty
> sure that, on the set in question, the scan's being generated OK, just
> not getting to the scan coils - monitoring for _that_ would need
> physically separate wiring (like the sense wires on a bench power
> supply), and I doubt that that is ever done.
I see what you mean. I only ever recall seeing four wires from the PCB to the
> >> > By the way - the person who said most modern CRT sets (triggering
> >> > others to comment on that combination of words!) shut off to protect
> >> > the tube in the event of such a scan collapse: how do they _know_?
> >>
> >> Well I don't *know* but if you integrate the frame scan waveform and if
> >> it falls below a certain level assume the scans have collapsed.
> >
> >We know what circuitry most CRT monitors and TVs contain because once upon
> >a time we used to work with this stuff every day and we've seen the
> >circuit diagrams.
> >
> >Rod.
> >--
> >
> I didn't mean the people don't know; I meant how would the circuitry
> "know" (that there was/is a fault). RS has supplied a possible mechanism
> - though that assumes the circuitry generating the scan waveform has
> failed, and his method would indeed detect such a problem; I'm pretty
> sure that, on the set in question, the scan's being generated OK, just
> not getting to the scan coils - monitoring for _that_ would need
> physically separate wiring (like the sense wires on a bench power
> supply), and I doubt that that is ever done.
scan coils, so no "sense wires" coming back from the coils themselves, just a
circuit on the main board to detect the presence of scan current, or at least
the drive voltage. I suppose with some circuit designs it might be possible
for a break in one of those wires to cause scan collapse without the circuit
detecting it, but this is far less likely than a component failure on the
board itself, or mechanical stress on a soldered joint where a large
component also needs to be fixed mechanically to something else, such as a
heatsink. Anything that works can fail of course, but usually the safety
circuits catch the most dangerous or the most likely things.
Rod.
--
Rick
Jan 13, 2013, 11:32:05 AM1/13/13
to
news:upDLnz5A...@soft255.demon.co.uk...
O/C scan coils will usually produce a wavy line on screen instead of a
straight horizontal one, although if as you imply the fault is intermittent,
then I'd resolder the joints around the field output chip as the number one
starting point, a common fault on the Euro series of chassis.
If it uses a TDA 8175 which has failed, then if memory serves me correctly
these became very expensive and difficult to obtain and were replaced with a
different IC and a bag of bits in the form of a mod-kit, not really a job
for the faint hearted and IMV certainly not worth the time and expense on an
old CRT receiver.
straight horizontal one, although if as you imply the fault is intermittent,
then I'd resolder the joints around the field output chip as the number one
starting point, a common fault on the Euro series of chassis.
If it uses a TDA 8175 which has failed, then if memory serves me correctly
these became very expensive and difficult to obtain and were replaced with a
different IC and a bag of bits in the form of a mod-kit, not really a job
for the faint hearted and IMV certainly not worth the time and expense on an
old CRT receiver.
kleinstu...@gmail.com
Mar 21, 2014, 4:16:55 PM3/21/14
to
I did some poking with a plastic rod, and found that if I pushed a part to the left, the picture came back. There was a metal bracket next to the part, so I cut a piece of plastic slightly larger than the gap and wedged it in. Fixed!!! Crude and low tech, but effective.
Brian Gaff
Mar 22, 2014, 4:52:09 AM3/22/14
to
Sounds like a dry joint somewhere. Murphys law will dictate that to get at
and solder it half the inards will have to be removed...
news:5ac59882-2134-444b...@googlegroups.com...
and solder it half the inards will have to be removed...
Brian
--
From the Sofa of Brian Gaff Reply address is active
<kleinstu...@gmail.com> wrote in message
--
From the Sofa of Brian Gaff Reply address is active
news:5ac59882-2134-444b...@googlegroups.com...
Brian Gaff
Mar 22, 2014, 5:07:56 AM3/22/14
to
Which reminded me of a fault with an early Philips 1501 vcr, that would trip
out and release its keys intermittently. really annoying if on the old
kitchen clock timer setting while out.
In the end after a great deal of freezer spray and using it with the pcb
carrier open for many days, it actually turned out to be four rectifier
diodes in the power supply. The diodes were encapsulated in a kind of
blue/green plastic which had shrunk where the wires exited, and the flexing
had broken the internal connection to the actual diode resulting in a
thermal creep just enough to miomentarily break the connection. In one you
could actually wiggle the wire and see this. New ones of a different
construction were fitted and the probblems fixed. At the same time a good
clean up and the mod to the drum ruler was fitted to stop tape creasing.
out and release its keys intermittently. really annoying if on the old
kitchen clock timer setting while out.
In the end after a great deal of freezer spray and using it with the pcb
carrier open for many days, it actually turned out to be four rectifier
diodes in the power supply. The diodes were encapsulated in a kind of
blue/green plastic which had shrunk where the wires exited, and the flexing
had broken the internal connection to the actual diode resulting in a
thermal creep just enough to miomentarily break the connection. In one you
could actually wiggle the wire and see this. New ones of a different
construction were fitted and the probblems fixed. At the same time a good
clean up and the mod to the drum ruler was fitted to stop tape creasing.
Brian
--
From the Sofa of Brian Gaff Reply address is active
<kleinstu...@gmail.com> wrote in message
news:5ac59882-2134-444b...@googlegroups.com...
--
From the Sofa of Brian Gaff Reply address is active
<kleinstu...@gmail.com> wrote in message
news:5ac59882-2134-444b...@googlegroups.com...
J. P. Gilliver (John)
Mar 22, 2014, 7:42:06 AM3/22/14
to
In message <lgjivl$9dj$1...@dont-email.me>, Brian Gaff
comes _below_ what is a proper .sig separator!)
picture, _when_ I can get vertical not to collapse. I've had it apart
many times and not found the fault: resoldering at the tagboard where
the scan coils terminate seems to fix it, but not long after it's put
back together, it goes again, so I think that's a red herring.
Percussive maintenance usually brings it back, for a while. I usually
give up; they have audio description turned on, and if I actually need
to see the image, I just wobble my eyeballs up and down!
Three reasons they don't just replace it:
1. obviously, _they_ don't need it!
2. it was her father's, so there's a slight emotional attachment to it.
(Not ancient though - a good set; as I say, still gives a good picture
when working, and good sound.)
3. it has separate volume control for the headphone socket (which she
uses) - not unique, but (still) unusual.
(If anyone knows the answer, I'd be very grateful. Can't give the model
number at the moment though, as we're at opposite ends of the country.)
quoted by Stephen Fry (RT 24-30 August 2013)
<brian...@gmail.com> writes:
>Sounds like a dry joint somewhere. Murphys law will dictate that to get
>at and solder it half the inards will have to be removed...
> Brian
>
>--
(I _do_ wish you'd stop posting followups such that the original post
>Sounds like a dry joint somewhere. Murphys law will dictate that to get
>at and solder it half the inards will have to be removed...
> Brian
>
>--
comes _below_ what is a proper .sig separator!)
>From the Sofa of Brian Gaff Reply address is active
><kleinstu...@gmail.com> wrote in message
>news:5ac59882-2134-444b...@googlegroups.com...
>I did some poking with a plastic rod, and found that if I pushed a part to
>the left, the picture came back. There was a metal bracket next to the part,
>so I cut a piece of plastic slightly larger than the gap and wedged it in.
>Fixed!!! Crude and low tech, but effective.
>
>
My blind friends have a set - Hitachi I think - which gives a good
><kleinstu...@gmail.com> wrote in message
>news:5ac59882-2134-444b...@googlegroups.com...
>I did some poking with a plastic rod, and found that if I pushed a part to
>the left, the picture came back. There was a metal bracket next to the part,
>so I cut a piece of plastic slightly larger than the gap and wedged it in.
>Fixed!!! Crude and low tech, but effective.
>
>
picture, _when_ I can get vertical not to collapse. I've had it apart
many times and not found the fault: resoldering at the tagboard where
the scan coils terminate seems to fix it, but not long after it's put
back together, it goes again, so I think that's a red herring.
Percussive maintenance usually brings it back, for a while. I usually
give up; they have audio description turned on, and if I actually need
to see the image, I just wobble my eyeballs up and down!
Three reasons they don't just replace it:
1. obviously, _they_ don't need it!
2. it was her father's, so there's a slight emotional attachment to it.
(Not ancient though - a good set; as I say, still gives a good picture
when working, and good sound.)
3. it has separate volume control for the headphone socket (which she
uses) - not unique, but (still) unusual.
(If anyone knows the answer, I'd be very grateful. Can't give the model
number at the moment though, as we're at opposite ends of the country.)
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
Wisdom is the ability to cope. - the late (AB of C) Michael Ramsey,
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf
quoted by Stephen Fry (RT 24-30 August 2013)
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