1970 Tube Test Data Supplement For Hickok 539B And 539C Tube Testers

If you're lucky enough to own a Hickok 539B or 539C tube tester, you know how critical the right settings are for testing old vacuum tubes.

This is a piece of history—a 1970 supplement of tube test data specifically for those models.

It's brand new, old stock, meaning it's never been used.

It gives you the settings and data for a whole bunch of tubes that were current or relevant back in 1970.

It's made in the USA by Hickok.

If you're restoring old radios, guitar amps, or vintage electronics, having the correct data for your tester is a must.

This booklet helps you get accurate readings and keep your vintage gear singing.