NEC Monitor JC 1733 VMA (XE17) DOA

[Hank]

Just before NEC Monitor JC 1733 VMA (XE17) lost all brightness, it started
"cycling' from dim to dark almost like turning a pot. Not at all like cold
solder (banging did nothing).

POST doesn't function. Suspect horiz. output, leaky cap in that stage.
Having no schematic, this baby is one step from the landfill. It was been a
flaky monitor since I purchased it new in 1994.

Anyone have any repair suggestions before I toss it?

Thanks!

Hank S.
Ft. Lauderdale

 

[techforce]

HOT is a Common Failure as well as the FET that supplies its B+.
These are a chore to disassemble due to design structure. The B+ FET is
probably a 2SJ306 or 2SJ307. It will read J306/J307 on the parts case. If
that or the HOT is Shorted, then replace both. If you need parts , I can
supply. Also there is bad solder on the Daughter board mounted Verticly on
one side sometimes.

 

[Hank]

Thanks Techforce for the hint. I've pulled enough sheet metal off this
monitor to build a utility shed, so I might as well check out the FET/HOT.
I'll let you know.
Hank S.

"techforce" <toomuchspam@messedup.com> wrote in message
news:GeQwb.2368$zu1.1445474@news2.news.adelphia.net...

HOT is a Common Failure as well as the FET that supplies its B+.
These are a chore to disassemble due to design structure. The B+ FET is
probably a 2SJ306 or 2SJ307. It will read J306/J307 on the parts case. If
that or the HOT is Shorted, then replace both. If you need parts , I can
supply. Also there is bad solder on the Daughter board mounted Verticly
on
one side sometimes.

 

[Heinz Schmitz]

On Wed, 26 Nov 2003 02:32:27 GMT, "Hank" <hank_@comcast.net> wrote:

Thanks Techforce for the hint. I've pulled enough sheet metal off this
monitor to build a utility shed, so I might as well check out the FET/HOT.
I'll let you know.

Just as Hemingway said, that no man drinks without a reason, there's
rarely a HOT or semiconductor that blows just for fun. Have a careful
look at the components around the blown device.
H.

 

[Asimov]

"Heinz Schmitz" bravely wrote to "All" (28 Nov 03 14:53:12)
--- on the heady topic of "Re: NEC Monitor JC 1733 VMA (XE17) DOA"

HS> From: Heinz Schmitz <HeinzSchmitz@gmx.net>

HS> On Wed, 26 Nov 2003 02:32:27 GMT, "Hank" <hank_@comcast.net> wrote:

Thanks Techforce for the hint. I've pulled enough sheet metal off this
monitor to build a utility shed, so I might as well check out the FET/HOT.
I'll let you know.

HS> Just as Hemingway said, that no man drinks without a reason, there's
HS> rarely a HOT or semiconductor that blows just for fun. Have a careful
HS> look at the components around the blown device.
HS> H.

Power glitches can fry them easily. Wanna do a test? Turn your tv on and
off fast continuously for about 5 minutes and see how long it can
survive. On a similar vein, when the first pc/xt's came out our tech
school instructor would swipe his hand across the keyboard and crash
every computer he did this to. He would leave class laughing
uncontrollably. He worked mostly on mainframes...

.... I ran Doublespace on my monitor & get 2 more TV channels.

 

[Heinz Schmitz]

On Friday, 28 Nov 2003 14:16:44 -500, "Asimov"
<Asimov@-removethis-bbs.juxtaposition.dynip.com> wrote:

HS> Just as Hemingway said, that no man drinks without a reason, there's
HS> rarely a HOT or semiconductor that blows just for fun. Have a careful
HS> look at the components around the blown device.
HS> H.

Power glitches can fry them easily. Wanna do a test? Turn your tv on and
off fast continuously for about 5 minutes and see how long it can
survive.

I wouldn't agree that turning the set on and off continuously for
about 5 minutes would come close to "normal use", nor to the power
glitch we can statistically expect .
Had I just replaced every blown semiconductor with a new one and
turned on the device without further checks, I'd have created quite a
semiconductor cemetery here.

On a similar vein, when the first pc/xt's came out our tech
school instructor would swipe his hand across the keyboard and crash
every computer he did this to.

That depended on the program being run. I had the chance to get my
programs tested for cat-proofness. dBaseIII was especially critical
for being crashed by my cat walking over the keyboard.
H.