Anyone know the Harman Kardon TC35 turntable?

I need to know the power output of the transformer/power supply and what pre-amp to get?
Good luck with that one.
I believe you are referring to the T35C turntable. They were very highly regarded when they were made in the mid 1980's. Very good TTs for the money, but the higher end models were better sounding and were even a better value.

The T20 went for ~$275, T40 ~$375, and T60 ~$475. The model numbers ending in 5C (instead of 0), were made a year or two after the T20, T40, & T60. There was very little difference between the two lines of TTs, but the '5C' series had an extra feature or two and were priced higher.