Follow up. Found some posts in previous posts last april. Yes they do have ridges on top so that should point them toward Amperex or Philips. But that doesn't explain grey pins if they are Amperex.
A gentleman said they would be Sylvania because they were the only ones making grey pins in 7308. But then, why would they be marked the europeean code E188CC. Those tubes have been supposedly picked from Polaris submarines.
A gentleman said they would be Sylvania because they were the only ones making grey pins in 7308. But then, why would they be marked the europeean code E188CC. Those tubes have been supposedly picked from Polaris submarines.