Here you go guys, here is the repair mod for the backlight.
- Remove top and bottom cover.
- Remove the 4 screws holing on the face, 2 on left and 2 on right of face holding it to chassis. Theres 1 ribbon cable connecting the face to main unit, just pull strait out.
- Remove knobs just by pulling them off. VFO just pulls off also.
- Unplug all ribbon cables on back of face, number them with a permanent marker if you think you might mix them up.
- There is 5 screws holding the top circuit board in, take them out and lift up board, be carefull and feed 2 of the ribbon cables through the board. On the back side of this board there are 2 steel boxes on the board. Take the top off of the biggest one.
You will see a small square transistor with the #B1201 on it. This is the problem transistor thats been giving backlight problems.
This transistor has no way of cooling laying flat on the board.remove this at your own risk. You have to have a small tip iron and a good set of eyes and steady hands. The center leg on the transistor is cut off, this is the ground leg, and the top of the trans is soldered to the board.
Heat the top of the transistor and lift it and it will come loose,then unsolder the legs and lift. Remember which way it came out. Take the new trans and don't cut the center leg off, the center leg needs to be soldered where the top of the transistor was soldered. And the other 2 where they were from the start, leaving the part standing up instead of laying flat on the board.
Now push the transistors side against the metal box and put some heatsink compound around the transistor and between the part and box, now it can keep cool.
Thats it, put the top back on and put the unit back together. Replacment part #s are NTE2525 or 2SA1244 or 2SB1201, good luck and take your time.
Works well
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