[R-390] Ballast Resistor, 3TF7

[Scott Bauer]

 I have been going through my tube inventory and ran across an 
interesting ballast
tube. I have only seen one of these before. With hope someone here might be
able to help me identify it. I cant find a cross reference.
 It is made by Victoreen. Marked.3Z6925-3.38 resistor, thermal. CRM 
300-8 13602-PH-53
Motorola Inc Chicago, Ill. 1/56. The tube itself is marked 300-8 Victoreen
 I am hoping it will cross over to a 3TF7. They are identical looking.

 Thanks for any help.    Scott W3CV