HP 1730 -dead on arrival

[xtraelectronics]

An HP model 1730 landed on the bench, dead. No LED, no response whatsoever. Initial inspection showed no bulged caps, signs of heat, or blown fuses. The power supply was working. Normal voltages were being produced, with the PSU running and disconnected from the video board. When the video board was plugged in, the "5 volt" rail began to fluctuate. At first I thought it might be the video processor IC. Then after testing those pesky little surface miount caps on the video board, I found one that was almost 15 Ohms ESR! (That is the one circled in yellow) Replaced it, and now we have a working monitor!
So, I guess I learned here that just because the symptom looks like a PSU problem, doesn't mean it is. ALL caps are suspect until proven good.

[EGuevarae]

Re: HP 1730 -dead on arrival

So, I guess I learned here that just because the symptom looks like a PSU problem, doesn't mean it is. ALL caps are suspect until proven good.

That's why you check first the voltages coming out of the PSU.
But great work anyway. No component is innocent until they prove it!