From SimonUK:





Click for larger image of above

This device goes under different names; "dynamotor", "genemotor" or just plain "rotary converter". These were very common in military gear, and this example looks of the WW2 era. They were particularly common in aircraft and other mobile applications to provide the high tension for vacuum tube equipment from a low voltage DC supply; typically 12V(road vehicle) or 28V(aircraft) This one would be from a radio transceiver. The lower voltage output is for the receiver and audio stages while the higher voltage powers the transmitter output valve.
Rotary converters like this have also been made to produce AC output with slip rings substituted for the brushes on the output winding. These were used where the output had to be a sine wave or of high power, as vibrator or early transistor inverters give out a square wave of limited power. These days even ordinary bipolar transistors are becoming obsolete for voltage conversion, with more efficient MOSFET's taking their place.

The stub shaft and mounting flange were probably used to attach a blower wheel to cool the equipment.

I'd agree, it certainly looks like the type of dynamotor which was used extensively at one time to power valve/tube equipment in mobile applications.

Whether the HT voltages you obtained would be those which were originally specified for this unit is hard to say though. 600V D.C. wouldn't be at all unreasonable for high-power transmitter finals, but 360V sounds a little on the high side if it was for feeding the general receiver and signal stages. If used for R/T, it might have been used for supplying power to the modulator, which on an A.M. transmitter needs a substantial amount of power (about 50% of the power needed to generate the R.F. carrier). The other stages would then be run via decoupled reduced voltages, as in line-powered equipment.

The voltage was higher than 600V D.C. It was out of range on my multimeter. My 1000V meter didn't want to play when I tested it. I'm pretty certain there was an AVR used to regulate the voltage as one of the field wires is way longer than the other. It'll make an interesting wee display at the next vintage rally I attend with my old generators and stationary engines.

Here's a link to my youtube channel where I'm starting to put some videos of my stuff. http://www.youtube.com/user/simov8chevy

There is the possibility of the motor portion being for 6V and not 12, especially if it was for a car radiotelephone. Some Genemotors were meant to be used with a carbon pile regulator. I have one such item in my collection. It's meant for a 24 (28V) supply with carbon pile regulator which drops the supply to 18V for which the input is designed. A carbon pile regulator is an electromechanical voltage regulator that works on the principle of carbon discs being pressed together at a greater or lesser pressure to control the resistance. What forces the discs together is a spring with a solenoid to offset the spring pressure. Increase the solenoid voltage and carbon pile resistance goes up.
So, the carbon pile is in series with the genemotor input with the solenoid across the genemotor input. If supply voltage rises, which it will when the output load is small, then more current into solenoid, carbon pile resistance increases and genemotor input drops. Simple and effective enough for the circuitry it powers. Voltages of 300 and 600 are certainly not unsual either. I use 24v or 18v genemotors on 12V and get a proportionally lower output which is more convenient for typical valve receiving applications.
There is indeed a blower attached to many units, and sometimes a channel switching mechanism in aircraft transceivers also coupled to the drive shaft.