choosing a monitor

CRT Monitor only displays a color point in the center of screen
Posted: Feb-24-2014 8:04 AM
Join Date:Feb-24-2014
Post: 1

Many thanks for all of you that dedicate part of your time to help the others!

I have an "El Cheapo" monitor branded as Haier model 1772EH, Product Name: HV-705CS

the first week that I started to use it the monitor works fine except for the image making some periodic enlargement and decreasing again, like it were breathing. at the second week the image starts to have some kind of interference in the vertical plane. like the image were oscilating (shaking) periodically form left to right and right to left, about 5 milimeters in each direction.

I changed the main filter capacitor 400V 150 microF and another labeled at 50V 3.3 microF with two identical ones.

but now when I turn on the monitor only appears a single colored point in the center of the screen!!!

question one: if one of the two replacemente capacitors were bad which is the prime suspect? the main or the other at 50V?

question two: will this procedure solve my problem or am I taking the wrong way changing the caps?

many thanks in advance,


Posted: Apr-1-2015 11:38 PM
Join Date:May-10-2011
Post: 24

check the yoke connections and solder in the yoke circuit. mesur the horizontal coil. it should be around 1.2 to 2 ohms. meny chassis will develop enough higf voltage to light the tube with an open horizontal yoke circuit. What it sounds like you had a bad connection all along and hanlding the chassis installin your caps finihed it off. If soldered in corectly the caps have nothing to do with your issue

sign in to post reply