Preamp Tubes 12AU7 – Underscore radio

TWO RCA ECC82 12AU7A Tubes /Amplitrex Tested/ Halo / 1973 Long Grey Plates

Tubes test at 2000, 1900 and 2090, 2100 where 1430 micromhos is pass/fail grade. #2: 9.7 / 10.4 mA.

TWO RCA ECC82 12AU7A Tubes /Amplitrex Tested/ Halo / 1973 Long Grey Plates

Tubes test at 2000, 1900 and 2090, 2100 where 1430 micromhos is pass/fail grade. #2: 9.7 / 10.4 mA.

TWO RCA ECC82 12AU7A Tubes /Amplitrex Tested/ Halo / 1973 Long Grey Plates

Tubes test at 2000, 1900 and 2090, 2100 where 1430 micromhos is pass/fail grade. #2: 9.7 / 10.4 mA.