 Posted: Thu Sep 18, 2008 9:43 am Post subject: |
|||
Sorry, I have since got rid of the lcd. The backlight went out and I gave up on it  |
|||
| Posted: Mon Sep 08, 2008 7:26 pm Post subject: |
|||
As it is a 4 month old post, you may have better luck trying to email him direct |
|||
| Posted: Mon Sep 08, 2008 7:16 pm Post subject: |
|
| edtrussell, are you still alive? | |
| Posted: Thu Sep 04, 2008 6:33 am Post subject: |
|
| Hi edtrussell, is there any chance that you can make the photos of the IC (8DIP) and FET transistor, which are located in the power section after filter capacitor, because one of the mechanics changed those parts and I'm not sure for the values. If you have schematic diagram, or repair manual, of the power supply module, that will help a lot. Thank you in advance |
|
| Posted: Mon Apr 21, 2008 7:02 am Post subject: |
|
| Normaly, no buzz should be heard from the transformer of a SMPS. The only sound one has to expect is a high-pitched whistle, in case of older SMPS switching frequency is near or within the audible range. However, if you hear a buzz, then the transformer itself is probably not at fault. Check that you don't have too much ripple across the filter cap on the primary side. If one of the diodes in the mains rectifier bridge is open circuit, then it can cause much ripple. If the SMPS has a wide primary voltage range, i.e. 100-240 V , try running it on another voltage within the range and see what happens. Make sure that you have used correct types of caps at all positions you have replaced (correct capacitance and low-ESR caps where such parts were fitted from factory). |
|
| Posted: Mon Apr 14, 2008 8:49 pm Post subject: HP vs19e LCD - Power transformer problem |
|
| Hi, I recently replaced the caps on a HP vs19e LCD. Now there is a buzz coming from the power transformer that gets louder when the lcd is turned on or off then gets much more quiet as it runs. Is this normal for a power transformer? If it needs replaced can someone point me to a place that sells a compatible part. Thank you. Here is a photo of the part http://i258.photobucket.com/albums/hh253/edtrussell/IMG_0395.jpg It is the yellow one in the center. |
|