RCA Cunningham Radiotron Number Type 78 #78 Vacuum Tube Mesh Plate NOS-Testing Gebraucht 50B5 This Korean War-vintage tube has

This Korean War-vintage tube has US Army Signal Corps SC 402 contract codes and 1-44 date codes

new in box Sylvania-MANUFACTURED 7X7 tubes tested to spec on our Paul Hart-calibrated TV7/U

It measured an almost-perfectly-balanced 59/57 where minimum (65%) is 40/40 and 100% is 62/62

Sorry I cannot say how they sound

GM-BRANDED 6SK7 tested as good on our Paul Hart-calibrated TV7/U

RCA Cunningham Radiotron Number Type 78 #78 Vacuum Tube Mesh Plate NOS-Testing Gebraucht 50B5 This Korean War-vintage tube hasThis mesh plate RCA Cunningham Radiotron number 78 tube tested 54 on our Paul Hart calibrated TV7 U where minimum (65%) is 36 and 100% is 56. 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. 1. MOST FORMS OF SHIPPING EXCEPT MEDIA MAIL ARE AUTOMATICALLY INSURED UP TO $100. ETSY