John-Del wrote:
On Thursday, November 9, 2017 at 5:58:53 PM UTC-5, Michael Terrell wrote:
bitrex wrote:
Not exactly a sophisticated piece of test equipment, but lets you eject
bad metal enclosure tubes early:

https://www.dropbox.com/s/m5b4ogl4pqn8tu1/IMG_20171109_110954264.jpg?dl=0

(all the metal tubes in the 1935 table radio passed)


A common as dirt filament tester. They were common as dirt, and sold
for about $3 in the early '60s. They hyped as real tube testers.

Not sure how they were hyped, but we used them all the time in the 70s to locate an open tube(s) in series sets. We kept one in our road tube caddy; it even used the same "cheater" cord as the TV did. You'd be surprised how many low end TVs used a series string back then and how often a dead TV was an open filament.


No surprise at all, since I worked in a radio & TV shop at the time.
DIY types would see ads for them, and bug the shop to buy one for them,
even after telling them that it only looked for open filaments.