5R4GY, rectifier tube Calvertron, made in Holland, black base, double D getter, original boxes. Great rectifier valve.
Click to see all 5R4 Rectifiers in stock
5R4GY, rectifier tube Calvertron, made in Holland, black base, double D getter, original boxes. Great rectifier valve.
Click to see all 5R4 Rectifiers in stock
Do you have any 5R4GY, rectifier tube Calvertron, made in Holland left in stock. If, so how much are they each. Was Calvertron a tube manufacturer, or a supplier. If a supplier, who would have made these tubes.