Monitor Picture Jumpy

[George S]

I have a NEC JC-1576VMA monitor that when first turned on the picture is
jumpy for a minute or so. Then it settles right down into a great picture,
good color and perfectly clear. I have torn it down and I am testing the
elect caps right now. So far there are four caps in the power supply with
high ESR. Is there anything else I need to check before putting this monitor
back together?
Thanks, George

 

[Jerry G.]

If the picture is jumpy, you may also have many high ESR caps in the
sync and video paths. It would be wise to check all the caps in the
set. I have had many high ESR caps cause various faults in many cases.
In many models of sets, most of the time after a set is about 5 to 7
years old the caps start to go high in ESR.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
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"George S" <george996@olypen.com> wrote in message
news:vl08qjnab4eebf@corp.supernews.com...
I have a NEC JC-1576VMA monitor that when first turned on the picture is
jumpy for a minute or so. Then it settles right down into a great
picture,
good color and perfectly clear. I have torn it down and I am testing the
elect caps right now. So far there are four caps in the power supply
with
high ESR. Is there anything else I need to check before putting this
monitor
back together?
Thanks, George

 

[Sam Goldwasser]

"George S" <george996@olypen.com> writes:

I have a NEC JC-1576VMA monitor that when first turned on the picture is
jumpy for a minute or so. Then it settles right down into a great picture,
good color and perfectly clear. I have torn it down and I am testing the
elect caps right now. So far there are four caps in the power supply with
high ESR. Is there anything else I need to check before putting this monitor
back together?
Thanks, George

Any other caps you haven't checked.

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[Asimov]

"George S" bravely wrote to "All" (29 Aug 03 21:08:37)
--- on the heady topic of "Monitor Picture Jumpy"

By jumpy I assume you mean up and down, so this implies the vertical
system. Besides the obvious electrolytic capacitors, I would look for
any zener diodes in the vertical areas. These are used as voltage
references and clamps. For some reason they have an odd tendency to go
intermittant and cause just this type of brief failure as they warm up.
Try some freeze spray on any suspect zener in the vertical area. Proding
with a long plastic rod may turn up something but be very careful of
High Voltage inside!!!.


GS> From: "George S" <george996@olypen.com>

GS> I have a NEC JC-1576VMA monitor that when first turned on the picture
GS> is jumpy for a minute or so. Then it settles right down into a great
GS> picture, good color and perfectly clear. I have torn it down and I am
GS> testing the elect caps right now. So far there are four caps in the
GS> power supply with high ESR. Is there anything else I need to check
GS> before putting this monitor back together?
GS> Thanks, George

.... You may be a tech if you're entertained by a 6-pack and sparking HV.