Siemens
Siemens E88CC 6922 Gray Shields
Siemens E88CC 6922 Gray Shields
NOS
Near NOS
Professional Tube Testing
This set was tested and certified by RoeTest V11 Professional Tube Testing System with the following result:
Tube 1:
Measured transconductance(GM): 12.46/11.11 mA/V - 100%/89% (100% = 12.5 mA/V)
Measured plate current(IA): 18.209/15.734 mA - 121%/105% (100% = 15 mA)
Tube 2:
Measured transconductance(GM): 11.89/9.94 mA/V - 95%/80% (100% = 12.5 mA/V)
Measured plate current(IA): 16.401/14.174 mA - 109%/94% (100% = 15 mA)
NO shorts, leakage or gas. NO noise or microphonics.
Curve trace is also included in the original RoeTest report.
Appearance & Cosmetic condition
Despite some loss of paint on one of the tubes, this pair overall is in great cosmetic condition. The 3-line Munich date codes etched on the glass are visible on both tubes although you may need to look closer to see them completely:
A0 1‡ 4F (A0 = E88CC, 1‡ = Munich, 4 = 1964, F = June)
A0 1‡ 5K (A0 = E88CC, 1‡ = Munich, 5 = 1965, K = November)