5 General Electric GE 6SF7 Vacuum Tubes Valves Lot Of Five 6AC7 Octal OM2 These four milspec Sylvania 5Z4

These four milspec Sylvania 5Z4 rectifier tubes were tested on our Paul Hart-calibrated TV7/U for shorts

They have great bass and sparkling highs and Mann's voice is warm and clear as a bell

two additional

copiously-illustrated book is in excellent condition

(New US-made 7408s typically test with plate current from the mid-teens to mid-30s with transconductance from 2300 micromhos or so

5 General Electric GE 6SF7 Vacuum Tubes Valves Lot Of Five 6AC7 Octal OM2 These four milspec Sylvania 5Z4These five GE 6SF7 tubes were tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. They tested as follows: 56 32, 66 35, 74 55, 77 52 and 82 48 where minimum (65%) is 50 40. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT ETSY SISTER SITE "LOWTECHTWOO" AND OR CALL OR TEXT US AT 202 372 6931 IF YOU DO NOT SEE WHAT YOU NEED OR HAVE ANY QUESTIONS.