Great tube manufactured on Blackburn UK , good tube for POWER SUPPLY on audio application.
TV7A/U SETUP AND VALUE RESULTS:
PLATE 1: JS0-6000 BIAS 0 SHUNT 70 RANGE A PRESS 3 MIN. VALUE 40 = 66
PLATE 2: JS0-4000 BIAS 0 SHUNT 70 RANGE A PRESS 3 MIN. VALUE 40 = 68
QUICK TEST ON OUR HOME MADE AMPLIFIER AND PREAMPLIFIER LIKE IN PHOTO:
SE VT-100 / 807 10W "A" CLASS
SRPP 6SN7GTB PHILIPS-MINIWATT