This has been a weekend of electronics experimentation at my house.
I had the distinct pleasure of taking a day of vacation on Christmas Eve. Unfortunately, I had the distinct displeasure of finding Christmas Eve morning that my Samsung LED DLP television decided it did not want to operate.
This TV is connected to my home theater PC, so when I saw a message superimposed on the screen that said "Check No. 3 fan" I thought it was a cooling fan on the PC.
I pulled up my PDF version of my motherboard manual and searched it for a fan labelled No. 3. It wasn’t to be found anywhere.
Searching was easy using Adobe Acrobat 9 or using Foxit Reader (I tried both). I even searched for "fan" and found the references, but they were labelled as to what they cooled, not by number.
Finally, I went to my web browser and searched for the message — and found it on some posts about Samsung DLP televisions. It appears that the fan is used to keep the LED light source from overheating.
About this time, I also realized that the television was off. I didn’t remember turning it off, so I turned it back on. The message was still there. In case it might help, we unplugged the TV for a few minutes and then plugged it in again. No change. But, this time, I left it on and paid enough attention that I realized the TV shut down automatically several minutes after being turned on.
By this time, it was noon on December 24th. The Samsung web site referred me to two warranty repair companies in my city. Of course, you can easily imagine that both had already closed for the holiday weekend. If they weren’t already closed, getting a housecall at that point would have been a miracle.
I ended up pulling the new, smaller television from the bedroom and putting it in the den so we had something we could watch. Remember "picture in a picture" mode? That’s what this little TV looks like, sitting in front of the big screen.
This Samsung television is 19 months old, which is way too soon to be having parts failures. My old Hitachi rear-projection TV didn’t have a problem for 11 years. We had replaced it because it finally did have a serious problem with its display system, such that it would not remain calibrated.
My old home theater PC was hooked to the Hitachi TV using a long, standard, VGA monitor cable and an audio cable. I decided to use those cables to connect to the temporary television.
With the VGA monitor cable connected to the PC VGA input on the television, I had the video signal. It looked strange — there was a Windows logo background, but nothing else showing. I finally realized that the TV’s resolution was 1280×720, while the PC was set to 1920×1080. Not only that, but the entire normal display was to the left of the screen and the display I was seeing was additional screen desktop space.
What was happening? I had connected the VGA cable to the video card and to the small television. But, the video card also had a HDMI cable still plugged into it, and that was plugged into the big TV.
So, the video card was smart enough to realize that it had two monitors at two different resolutions, and it expanded the desktop to take in the small TV’s desktop space, too. Neat idea, but confusing when you’re not expecting that!
Meanwhile, I connected the audio cables to the little TV, but no sound. Hummm… that doesn’t sound good. I had unplugged them from the big TV and plugged them into the little TV, but no change.
I turned on the big TV and found it still had sound…
So, I looked at it again and found another audio cable connected to it. This one was a long stereo mini-plug at one end and the same at the other end. But, the other end wasn’t plugged into the home theater PC.
That’s when I had the "Ah, hah!" moment.
HDMI cables carry video and audio. I knew and expected that from DVD players and such. But, with my home-made home theater PC, I had sound outputs from the motherboard and the HDMI connector was on my $40 video card. I didn’t expect the HDMI cable to have the audio on it.
But, sure enough, the video card was reaching out to the audio stream on the motherboard, was grabbing it, and was adding it to the video card’s HDMI cable output!
I unplugged the HDMI cable from the big television and plugged it into the small one.
IT WORKED! Picture! Sound! YEA!
Now, I’m just waiting for Monday to call the repair man…
[The repair man took two weeks to arrive!]