B&K 747B Mutual Conductance Tube Tester for sale. This is one of B&K’s best late-model testers, capable of testing a wide range of tubes with precision. Compact and easy to
B&K 747B Mutual Conductance Tube Tester for sale. This is one of B&K’s best late-model testers, capable of testing a wide range of tubes with precision. Compact and easy to