May I suggest that if the bulbs burn out often they may be getting too much current. Consider putting a resistor in series to make tha bulbs lat longer. * * It's a real pain in the %$#@* to replace the display bulbs in * any on the x75 * series radios. I've had to do it several times in my 575. I * have the service * manual for the 575 and it was not a lot of help. *