Rigol scope LCD problem

[a7yvm1...@netzero.com]

DS5102C, color LCD scope. When turned on, the leftmost quarter has
vertical stripes, the affected column is dead.

It looks like specific sub-pixels are not responding. R in one row is
dead, then G a few rows down, then B, repeat 10 times.

http://img593.imageshack.us/i/rigollcdscreen.jpg/

Thing is, after a few hour warm up, it works normally.

What is the most likely suspect before I go in and strip it down? Is
it likely to be simply a bad harness somewhere that needs reseating?
Or do I need to take apart the panel and fiddle arround with something
more arcane?

I don't think there's zebra strips in these things these days.

[N_Cook]

<a7yvm1...@netzero.com> wrote in message
news:9e7527b4-b0af-4d2b...@y26g2000yqd.googlegroups.com...

I would get inside and lightly probe with fingers, either final bond to the
LCD failed somewhere or solder problem on a demultiplexer chip. If bond
failure , do not try debonding and rebonding . That plastic reticulated
foam, pan scourer, pressed against the suspect area and padded/braced
against something is about all you can expect to remedy, unlikely to be
zebra strip.

[Jamie]

a7yvm1...@netzero.com wrote:

I wouldn't put it past them to have zebra strips in there how ever,
since they can't use leaded solder any more in production items it's
very possible you have a solder joint issue in the screen itself or it
could be the header on your board.

Use circuit cooler on suspected areas after warm up to recreate the
problem.

Jamie

[a7yvm1...@netzero.com]

On Apr 11, 2:41 am, "N_Cook" <dive...@tcp.co.uk> wrote:
> <a7yvm109gf...@netzero.com> wrote in message

Thanks, I haven't taken it apart yet but I think it's just a PS, a
mainboard and the front panel with the LCD, BNCs and buttons.
I'm hoping a simple reseating will fix it.
Thanks for the tips.

[Jeff Liebermann]

On Mon, 11 Apr 2011 17:42:27 -0400, Jamie
<jamie_ka1lpa_not_v...@charter.net> wrote:

> Use circuit cooler on suspected areas after warm up to recreate the
>problem.

Good idea, but keep the cooler spray away from the CCFL lamp(s). I
sprayed one while it was running and instantly cracked the tube. I
don't know if this is a one-time problem, or is typical, but it might
pay to be careful. Maybe a hot air gun (on low heat) when the panel
is cool, or just massaging the circuitry looking for intermittents,
might be equally productive.

--
# Jeff Liebermann 150 Felker St #D Santa Cruz CA 95060
# 831-336-2558
# http://802.11junk.com je...@cruzio.com
# http://www.LearnByDestroying.com AE6KS

[Jim Yanik]

Jeff Liebermann <je...@cruzio.com> wrote in
news:i8j7q6dd45ut6ro2c...@4ax.com:

> On Mon, 11 Apr 2011 17:42:27 -0400, Jamie
><jamie_ka1lpa_not_v...@charter.net> wrote:
>
>> Use circuit cooler on suspected areas after warm up to recreate the
>>problem.
>
> Good idea, but keep the cooler spray away from the CCFL lamp(s). I
> sprayed one while it was running and instantly cracked the tube. I
> don't know if this is a one-time problem, or is typical, but it might
> pay to be careful. Maybe a hot air gun (on low heat) when the panel
> is cool, or just massaging the circuitry looking for intermittents,
> might be equally productive.
>

I used to spray the cooler on a Q-tip swab and apply the swab to a
suspect component I wanted to chill.

or you could rig some short of paper shield to keep the spray away from
other parts.

--
Jim Yanik
jyanik
at
localnet
dot com