Well, after several years of faithful service, the backlights for the display on my Uniden BC8500XLT scanner went out. At first the display lights would dim slightly by itself. Then after a while it would get erratic --- dimming to out completely then suddenly coming back on. Finally they went out altogether. The "dim" button still controlled the lighting and dimming of the LED's in all the pushbuttons though.
I got tired of not being able to see my display and since I had the service manual, I took it apart to check it out. Turns out transistor Q 46 was bad. The original is a 2SC 2120-Y which crosses to SK3849 or NTE293. The replacement is in a T092 Giant package whereas the original was a standard T092 package. Pinout is the same: ECB. If you can't find the SK3849 or NTE293, you can also use an NTE289A transistor.
The new transistor fixed it right up and the display lights are functioning perfectly again.
It was fairly simple to replace the transistor. Just take the top and bottom metal covers off the radio. The transistor is located near the front panel assembly. I was able to slip my soldering iron and solder sucker in there without having to remove the front panel assembly.
Hope this helps out other folks that experience this problem with the display lights.