You are not imagining. All I have ever seen were metal, aluminum I presume, and exactly as you describe. Most in-store consumer tube testers were fitted with these pin straighteners and so were many technician level tube testers.
I only recall straighteners for 7 and 9 pin tubes, but there may have been other configurations. I also remember 7 and 9 pin riser sockets. They might have been 1/2 to 1 inch tall and could be secured to your tube tester socket with a little screw and nut - probably 4-40. You would mount this on your tube tester socket and it would take the insertion/removal abuse of tube testing. When it became unreliable you would replace it. That way you didn’t wear out the “real” socket on the instrument and end up having to unwire and replace it.
On 28Jan, 2016, at 12:26 AM, edbreya@... [TekScopes] <TekScopes@...> wrote:
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