A plastic four-pin base with binding post on side. Tipless S-shaped envelope mostly silvered on inside. Stamped on one side: "Mullard / Pentone / Registered Trade Mark / PM24 / BVA". BVA is British Valve Association, a trade consortium. On other side: "Registered Trade Mark / Radio Mullard Valve / Protected By Patent / KB / Dummy." "A" molded on base near one pin. Philips-Mullard, See Reference: Tyne, "Saga of the Vacuum Tube," page 377-379.
A diode-pentode for radio frequency and intermediate frequency stages, 7-pin plastic base with central post. T-shaped envelope with mica insulator. Printed on paper label: "Tung-Sol Lamp Works Inc. / Newark, N.J. / Engineering Sample / Type 1SB6GT Date 4-21-[19]41. Reference: https://www.radiomuseum.org/tubes/tube_1sb6gt.html.
Plastic 6-pin base with aquadag coating, BT-shaped envelope. Base stamped: "RCA Radiotron / Made in U.S.A."; on envelope: "42". Reference: https://www.radiomuseum.org/tubes/tube_42.html.
Sylvania type 6BG6GA beam power tube. Plastic base with 8 pins. T-shaped envelope with top contact. https://www.radiomuseum.org/tubes/tube_6bg6ga.html.
An air-cooled transmitting pentode. Ceramic base with 5-pins, top contact. BT-shaped envelope. Printed on base: "RCA Radiotron / Licensed / only to / extent / indicated / on carton"; on envelope: "Made in / 803 / U.S.A."; inked on press: "A492D / 35474 / 10 205". Reference: https://www.radiomuseum.org/tubes/tube_803~3.html.
A plastic 7-pin base with center post, BT-shaped envelope, getter stain, aquadag coating. Stamped on base: "RCA". Reference: https://www.radiomuseum.org/tubes/tube_6f6g.html.
A pentode with 5-pin base, top contact, mesh plate. Markings: "Western Electric / USA / 309 A" "Voltage amplifier, variable-mu, suppressor-grid, pentode with indirectly heated cathode. The 309A tube is especially designed to minimize audio-frequency disturbances arising in the tube. The suppressor grid is permanently connected to the cathode within the bulb. Applications: Audio-frequency voltage amplifier, particularly in circuits in which the amplification is adjusted by varying the control-grid bias, and exceptionally low tube noise is required. Radio-frequency voltage amplifier." Reference: https://www.westernelectric.com/s/309A.pdf.
A vacuum pentode. Plastic base with 5 pins, tipless S-shaped envelope. Vertically-oriented collector, cylinder with wings, mica insulators at top and bottom of stem. Getter stain on inner wall. Base marked: "Crosley / Made in U.S.A. by / Arcturus Radio Tube Co." and "Licensed to extent indicated on carton." "33" stamped on base, "56" on top.
