(!!) (Recommended 27 Balloon) C-327 Cunningham Balloon mesh-plate used/very good 1930's (5.2ma)
(!!) C-327 Cunningham Balloon short mesh-plate used/very good 1930 (5.7ma)
(!!) ER-224A Eveready Raytheon Balloon used/tests very good 1930's (45/25) (4.1ma) (highest Ma)
(!!) UY-227 RCA Balloon NOS 1930 era (4.3ma)
(!!) UY-227 RCA Radiotron Balloon used/good 1930 era (3.5ma)
(!!) UY-227 RCA Radiotron Balloon used/good 1930 era (3.7ma)
(!!) UY-227 RCA Radiotron Balloon used/good 1930 era (3.8ma)
(!!) UY-227 RCA Radiotron Balloon used/good 1930 era (4.0ma)
(!) (#1 24A Balloon) 24A BRUNSWICK Balloon used/tests like new, small crack in base (48/25) (3.8ma)
(!) (#2 24 Balloon) 124 Crosley by Arcturus Balloon used/tests like new 1930's (48/25) (3.0ma)
(!) 247=47 RCA Balloon used/60-65% 1930's (20ma)
(!) 247=47 Tungsol Balloon used/good 1930's (23.2ma)
(!) 47 RCA Radiotron Balloon used/good 1930's (23.4ma)
(!) NY-247=47 National Union Balloon used/good 1930's (22.6ma) (and strong Gm)
(!) RY-247=47 Federal Supreme Balloon used/good 1930's (24.2ma)
(DISPLAY TUBE) 480 Deforest Audio Balloon shape glass 1930's (for display purposes only - does not work)
(DISPLAY TUBES) 80 Balloon shape glass 1930's (for display purposes only - do not work)
224 CECO Balloon used/strong 1930's (44/25) (3.0ma Gm=1000)
224 US Made Balloon used/tests like new 1930's no printing (50/25) (5.4ma Gm=1000)
24 Philco Balloon used/very good 1930's (3.3ma Gm=900)