View Full Version : DEAD monitor! help!!

11-22-2000, 06:08 PM
help i am trying to fix a Packard Bell monitor modle#1402s feb 1995
i have replaced a dead transistor #q415 it was ECG 375 part#
i am getting 175.9 volts when it should be 148 volts ,109.3 volts when it should be 70 volts and 0 volts when it should be 12 at test points on main
board i know this is in the power supply but have no idea where to find it all the transistors are checking good and i am at a loss to find the problem any help would be very nice.

11-22-2000, 11:21 PM
Todays monitors employ what is called a switch-mode type power supply, this is the same type of supply that is used for your desktop. The reason for the desktop supply being encased is there is LEATHAL and I do mean LEATHAL charges that can be retained even when unplugged. As you said 179.5v is should be 148v, it is retaining this DEADLY charge, and no matter how long you wait it will still be there. So one little slip of the hand and you will be six feet under. I suggest you go to your local tv repair shop and have them fix it. Most if not all should be able to repair it, as a monitor is actually easier to fix then a tv because it contains only 1/2 of the circuits of a tv. As my boss would say about me I am too blunt, that I have no people skills. I say when it comes to this, morally I can't allow a person to be endangered and possibly kill themself. The reason is I deal with this everyday as I work for a manufacturer of tv's and supply the service centres (trained technicians knowing the dangers of their trade) with support when they have problems and/or can't fix the tv. Sorry to be blunt but we're going to have leave it at this point.


[This message has been edited by Hardtek1976 (edited 11-22-2000).]

Paleo Pete
11-24-2000, 09:35 AM
I agree with Hardtek completely, if you're not VERY familiar with CRT repair, and qualified to work on one safely, I strongly recommend staying out of the monitor, for the reasons stated above, but I'll say it again...

The monitor contains capacitors and a CRT tube that retain high voltage charges when powered down and unplugged, and can seriously injure or kill clumsy humans. Capacitors retain these charges for several days, and the CRT can retain a charge for months, if not indefinitely. Stay out of the monitor unless you KNOW what you're doing.

Soon as I come up with all the answers...they change the questions!!

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