I have a Spectroniq PLTV-3250 which went completely dead after two years. Am told by the TV repair people that it needs a Power Supply Module. Is there any way you can send one to me in order to repair the...
MODEL: Spectroniq PLTV-3250
SYMPTOM: Totally Dead; no lights, no noises from inside.
SOLUTION: As most folks here know, It is most likely the power supply. After fixing a few of them, all having the same problem, I thought I would share this solution with those who possess electronic repair knowledge.
First, use this solution AT YOUR OWN RISK. DO NOT attempt the repair if you lack the necessary skills or equipment. I am NOT RESPONSIBLE for damage to the TV, to you, or to anything else if you proceed.with this repair. Read this post thoroughly before doing anything so you understand what skills and equipment are required.
Second, this is an ADVANCED repair; the board may be irreparably damaged if care is not taken.
Unplug the set and let it sit for about twenty minutes to let the High Voltage (+169 VDC) drain off. Then remove the back cover. Check again that the set is actually unplugged.
The power supply is on the left. Remove the screws holding the supply and turn it over, laying it on something that will insulate it from the TV chassis (a magazine for example). Check across the largest electrolytic cap (C1) with a multimeter to see if the high voltage is gone. If it is, proceed. If not, short across the large capacitor (C1) to finish draining it.
With a multimeter set on resistance (ohms) or diode test, locate Q7 and check it for a shorted condition. If it is, remove it VERY CAREFULLY. If it is not, STOP. This solution can not help you. It is surface mount, very small, and worse, glued down, so it is difficult to remove
NOTE: I cannot find any tech info on this TV, or a way to decipher the markings on Q7. Apparently, it is some sort of level-detecting switch. But once removed, it can be "strapped" with a diode and the set will suffer no ill effects.
Locate the small electrolytic cap close to pin 4 of the TEA1532A chip (C33). The anode of your diode (1N914 or equivalent) will be soldered to the positive terminal of this cap. Then locate the small electrolytic cap closest to pin 1 of the TEA1532A; the cathode of the diode will be soldered to the positive terminal of this cap (C32). Be careful to mount the diode such that when the power supply is re-installed, it will not touch the chassis or the board. MAJOR damage to the set will result if it does. Check your work to make sure there are no solder bridges or blobs that will cause shorts. Also, it is VERY IMPORTANT that the braided cables be taped well away from the power supply. If that braid touches the metallic parts of the supply, you will either blow the fuse or ruin the power supply. YOU HAVE BEEN WARNED!
Re-install the supply, raise the set to the vertical, check once more that all is well, then plug the set in. If the red light on the front panel is on, start smiling and use the remote to turn the set on.
Jul 11, 2009 |
TV Receivers & DVRs