Looking for info on 12mm stud mount transistor MEDL ESM 3004 C

[Kim Clay]

Large NPN stud mount device with "flags" for lead connections E & B.
73mm tall
22mm dia ceramic body
30mm OD mounting hex (27mm across flats)
12mm stud mount

1987-89 date codes

MEDL seems to be the old Marconi Electronic Devices Ltd.

These are mounted on water cooled heat sinks & (I think) used as
drivers for a SCR stack.

Thanks for looking - Kim

 

[gadcas]

Large NPN stud mount device with "flags" for lead connections E & B.
73mm tall
22mm dia ceramic body
30mm OD mounting hex (27mm across flats)
12mm stud mount

1987-89 date codes

MEDL seems to be the old Marconi Electronic Devices Ltd.

These are mounted on water cooled heat sinks & (I think) used as
drivers for a SCR stack.

Thanks for looking - Kim

I do have two of then

 

[gadcas]

I do have two of then they are a power transistor used commonly on the power section of Siemens X ray equipments