Matched Pair RCA Clear Top 12HG7 12BY7 Vacuum Tubes NOS-Testing LP SW 3386 gray bottle type / number

gray bottle type / number 41 tubes tested as follows on our Paul Hart-calibrated TV7/U:

This lot of five US-made 6AV5GT tubes were tested for shorts

Tube One measured 73/75 while Tube Two measured 75/76 where minimum (65%) is 56/56 and 100% is 87/87

This pressing has lightl surface noise audible in quiet passages and barely-audible in voice-level passages

Transconductance measured 2230 micromhos for Tube One (Missing centering pin

Matched Pair RCA Clear Top 12HG7 12BY7 Vacuum Tubes NOS-Testing LP SW 3386 gray bottle type / numberThis new old stock testing matched pair of RCA clear top 12HG7 tubes was tested on our Paul Hart calibrated TV7 U (on the 12BY7 setting) for shorts, gas and transconductance. There were no shorts or gas. Tube One measured 74 while Tube Two measured 78 where minimum (65%) is 46 and 100% is 71. These tubes have anode radiators for cooler operation and longer tube life; side O getters and excellent flashing. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES.