I'm not sure it's the right one. I will download the manual and check. EDIT!! I checked the manual - you do NOT want a 115NO90T!! The correct part is a 12NO90T. The thermal relay runs off the 12.6 volt heater circuit, not 115!! You can also use a 12NO120T, 12NO150T or 12NO180T - they just have longer delays. They are all over ebay; the trick is to wait for one that is under $10. They can also be found at hamfests and in old Tektronix tube 'scopes. Did you read the article in QST (May, 1995, page 84)?