Matched Pair Philco Number Type 78 #78 Vacuum Tubes Valves Engraved Hot-Stamped Base Mesh Plate Engraved Base

Matched Pair Philco Number Type 78 #78 Vacuum Tubes Valves Engraved Hot-Stamped Base Mesh Plate Engraved BaseThis matched pair of mesh plate Philco number 78 tubes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas and they measured as follows: 43 and 44 where minimum is (65%) is 36 and 100% is 55. 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

came from an excellent lot and should work fine

mica snubbers for increased rigidity and lowered microphonics and excellent flashing

MOST OF THE TUBES WE SELL ARE OVER 70 YEARS OLD

60/40 and 64/50 where minimum (65%) is 50/50 and 100% is 77/77

100% is 77/77

It measured 78/80 where minimum (65%) is 50/50 and 100% is 77/77

Date Codes: 1-43 and NK

6 milliamps' plate current and measured 1610 micromhos

on our Paul Hart-calibrated TV7/U where minimum (65%) is 31 and 100% is 48

nearly-perfectly-matched pair of GE 6SJ7s was tested on our Paul Hart-calibrated TV7/U for shorts

They are World War Two vintage and all have US Army Signal Corp SC 278 A codes

These tubes have acid-etched codes and designations as well as silk-screened 67-05 67-22 188-5 and 68-26 188-5 67-50 production run/provenance codes