Yellow spot in my 50" hitachi tv

The light engine needs replaced. If you order one check the serial number . If it has an A at the end the part will be different.

need the model number

Hi there,
We have the same exact problem with the same TV. We've only replaced the bulb once about a year ago. Don't know if it had anything to do with the fact that we now have a large yellow circle in the middle of our screen, which is about 7" round.
We only noticed the yellow mark about 4 months ago.
Hopefully someone will have a solution for us that doesn't cost an arm and a leg. Paid $2100 for this set and are a little disappointed.

Sounds like Calibration is needed on the projection internals. Your TV uses a rear-projection system and the problem is either in the imaging LCD Unit or the light filter. I see in a previous thread you have changed the bulb. You can invest in a voltage regulator to keep the hardware in factory condition.
Also you can burn a DVD of a stuck pixel remedy video and run it on the screen with full brightness and full contrast. This is used for plasma burns and stuck pixels on conventional Flat panel TVs but can repair color issues with projection systems. This therapy is focused on the imaging unit between the projector and the main drop of your tv.
please feel free to post a more in-depth description or any changes

you most likely have a bad light engine.

TV shows large red spot in middle of tv when dark show are on, you can see it more.  Now blue spots on upper right side too.  Spend way to much on this tv to have these kinds of problems only after 3 yrs.

I am slightly confused about the model of the television, because a 46F500 is a rear projection set that doesn't have a lamp. It has 3 picture tubes and I have a few of them in my shop right now that have the problem you reported. What we do to this set when it develops a convergence issue is to check each resistor around the convergence chips for discoloration, and replace any of them that have changed in value, along with the STK392-150 ic's. If you don't have an ohm meter and solder/desolder equiptment, you can usually get a shop to do this repair for 150.00 to 350.00. Parts will be 50.00 and labor , the rest, depending on the quality of repair shop that you use. Good luck, Russmann.

Good Day, dv28;
No, the lamp will not correct this. The TV has a bad light engine, it's very common for this TV and very expensive. Call the manufacture and try to get a concession for the part. They normally give it about 75% of the time.
Good Luck, big IRISH.

https://www.ued.net/ued/addItems.do?itemCode=HIPUX23682D

wayne, is it there as soon as the image comes up or does it have to run awhile before it appears? Let me know,