I never got around to posting the innards pictures from when I serviced mine, so here they are:
I have also decided that the regulated power supply is probably due to the transformer being a ferroresonant transformer as there is no electronic voltage regulation circuit present.
I got my Mark VI back when EG&G was still doing calibration. They might still be, but around ten years ago I heard the price had gone from $300 to $1200 just for the calibration. That lead me to believe EG&G didn't want to do them any more. But when they did, they would read the exposures, check the electronics, change the power cable, and include new compensators and a step tablet (uncalibrated).
I always used 10-2 for exposing film because of the lower illuminance and practical exposure time. 10-3 was way too bright and 10-4 might start showing problems with reciprocity.
With the 10-3 compensator, the exposure for 10-2 was 20.3mcs. I then used ND filters to adjust for the different film speeds. I used .6 NDs. They brought the exposures down to 4.78mcs for 100 speed films, 1.18mcs for 400 speed films, and 0.28mcs for TMZ and Delta 3200.
I've also worked with a Mark VII that had
10-2 = 681mcs
10-3 = 3440mcs
10-4 = 59.4mcs
10-5 = 29.2mcs
10-6 = 6.85mcs
The manual has a phone number for EG&G, but I also wrote down a number that might be one for the then calibration department. It is (800) 950-3441. They might still sell the compensators. BTW, I talked to EG&G once about finding a meter that could be used for the calibration of the sensitometers. For that kind of accuracy, it would have run around $4000 dollars. There is a lot of good information that can come out of a calibrated light source. It was well worth the $300.00 extra dollars for the calibration.
I had not seen this thread before, and I had a question. I use a densitometer occasionally, but never a sensitometer. I read your post about how to use one and I wanted to ask, is this is different than shooting a gray card at various exposures to cover the zones from black to white and reading the film on a densitometer to plot curves? Or is this just a machine that does this for you?
Not really. The Sensitometer is calibrated for time and light output and so is more accurate for all purposes. Units like this are used by EK, Fuji and Ilford to test films and papers. Our lab had several EG&G units.