I have a good sine-wave going in the final amplifier stage of a 33250A Function Generator. The protect diode VR1902 was shorted. The generator must have been hit with a high voltage UT Square wave pulser. The output of U1904 is distorted with very little negative going signal. I believe U1903 is bad also. If I lift its pin #6, it puts out a straight 16volts all the time even thought it has inputs.
U1903 is easy to get from Digikey, but not so much U1904 which is a custom Agilent/Keysight part and I am getting the idea that they won't sell it. Why? An entire board is something like $3300. I can buy a 33250A, used, on Ebay, for $2200-$2500. I would love to fix the one I had if I could only replace the final amplifier.
Thanks kindly,
Dave