Description

Vintage Mullard EF91 with very hot output! I’m listing it as reading 120 on output and 120 on life test because that’s as high as the 747B reads. Liquidating my fathers inventory of vacuum tubes and this was the single hottest tube I tested! This tube was in my fathers “service spare” inventory and should be considered used however tested better than NOS tubes of similar vintage! Tubes are tested on B&K 747B. Tubes are warmed for 5 minutes and then tested for shorts and grid emissions before having output tested. Output test os held for 10 seconds and life tear is held for 5 seconds or more (wait until reading stabilizes) As improper handling or faulty equipment can damage tubes, no returns accepted.