6S4A RCA USA black plate NOS 1970's (19ma)

6S4A RCA black plate NOS 1970's

19ma

Gm=3900

Good mA = 20+

Good Gm = 4000+ 

(the 6S4A features high plate current at relatively low plate voltages and is capable
of withstanding high pulse voltages)(Vfil=6.3V @ 600ma)
MAX Ratings: Vplate=550V, Iplate=30ma, Pout=8.5 watts
Typical Operation: Vplate=250V, Vgrid=-8V, Iplate=24ma, Mu=16.5, Gm=4500, Rplate=3700 ohms)

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