McVitie Weston valve collection, RCA Radiotron valve, type 30
- maker:
- RCA Corporation
RCA Radiotron valve, type 30, marked D4271, (RMW/D142B - McVitie Weston number), by RCA Corporation.
RCA Radiotron valve, type 30, marked D4271, (RMW/D142B - McVitie Weston number), by RCA Corporation.