Despite the fact that my Fusor setup has an oil diffusion pump in the high vacuum line, I could not resist the opportunity to acquire a (cheap) turbo drag hybrid pump, an Agilent (Varian) Turbo-V 81-M (image 1):
It was quite a surprise to find that the turbo pump had no damages and that the turbine rotor was spinning effortless, moreover the pump was about two and a half years old (image 2):
The problem with a cheap turbo pump is usually that no controller comes with it and also the cable is not part of the deal. With some efforts I was able to get an (also cheap) Varian TV 70 controller, which has the same specs (voltage etc.) as the original controller for this turbo pump (image 3), except for the frequency upper value (1250 Hz vs 1350 Hz). I expect that with a lower high speed frequency the pump will rotate maximally at 70,000 rpm instead of 80,000 rpm, which is probably not an issue for the vacuum that we use in the Fusor. The issue with the missing cable was resolved because an extension cable could be found, which gives me the connector for the pump and the cable, but not the connector for the controller. I intend to make a direct connection with the cable inside the controller at the back of the J16 connector (image 3).
The arrival of the turbo pump and the controller did not mean that I have abandoned the oil diffusion pump in the system. In my opinion it is a better option in view of the progress already obtained in the project: it works, it is easy to operate, it is failproof and other components have already been dimensioned onto this oil diffusion pump. In my long time professional job directing longterm nuclear projects it was never considered a good option to change parameters during the realization of a project because that would lead to failure or to a never ending project. It is difficult to escape from old habits!
Therefore I'm continuing now with constructing a baffle with integrated cooler/heater for the oil diffusion pump.
About that part more in a next update.