[3dem] Old Gatan 626 with new controller?

[Buecker, Robert]

Dear Colleagues,

we are currently trying to re-activate a Gatan 626 cryo arm (Philips version) built in 1985 (black dewar, instead of the new grey ones) for use in a Tecnai F20. We received it "as is", without controller.
Our first attempt at using a Model 900 controller (from a newer JEOL-type 626) on it was unsuccessful, the temperature shown was significantly off (roughly at room temperature when the arm was cooled).
We noticed that the old arm has only 5 contact pins (2x Heating, 2x Sense, 1x GND), whereas the new one has 7, and suspect that this difference (4-wire measurement on a thermistor maybe?) causes the incompatibility.
Did anybody encounter that problem and know how to make the old arm work with the 900 controller?

Cheers,
Robert

--
dr. robert bücker
 max planck institute for the structure and dynamics of matter
 atomically resolved dynamics department
 desy bldg. 99 (cfel)
 luruper chaussee 149
 22761 hamburg, germany
 tel. +49 40 8998-6278 / -86043
 mob. +49 157 70210628

 robert.buecker at mpsd.mpg.de
 http://www.mpsd.mpg.de/68786/Femtosecond_Diffraction