Re: Intermittent fault in Eizo 19" T766 CRT

Wiebe Cazemier <wiebe@xxxxxxxxxxxx> wrote in
news:e631c$4814fa58$d4cc82be$21713@xxxxxxxxxxxxxxxxxxxxxxxx:

On Sunday 27 April 2008 23:23, bz wrote:

[http://en.wikipedia.org/wiki/Trinitron]
Another feature was a three cathode single electron gun arrangement, in
contrast to the then-dominant (and still common) three gun arrangement.
Single gun systems tend to be easier to manufacture reliably, simplify
beam focus and control, and are less prone to inter-electrode short
circuits. [unquote]

Ah, that explains it.

Three guns means three filaments, three cathodes, and three sets of
focusing electrodes.
One gun means that the three cathodes all use the same focusing electrodes.


And the cathode line capacitor BTW, where is that likely to be
located? Near the flyback on the mainboard?

Sorry, no idea. But I think you are mistaking which capacitor is going
to be used to clear the short.

The question about the line capacitor was unrelated. It had to do with
another minor issue of this monitor (it slightly getting brighter over
time, ever since I got it), of which was suggested it could be this cap
which was degrading. While we were on the subject, I just thought I'd
ask.

Ah. I see.

I would expect a cathode bypass cap to be near the cathode.
On the other hand a cap involved in driving a cathode with a signal might
be near the video output. Sorry I can't help more.

I remember quite a long discussion somewhere about 'monitor too bright',
google may find it for you.

If I remember correctly, it was a panasonic monitor being discussed and two
fixes were mentioned. One involved going through the setup menu and the
other putting a resistor in parallel with another resisitor.
This may or may not be of any help to you.




--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

bz+ser@xxxxxxxxxxxxxxxxxxxx remove ch100-5 to avoid spam trap
.

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