Thomas Mayer returns with the Tube of the Month. This time the well known 2A3 valve. RCA probably made most of the 2A3s, but there are numerous versions by General Electric, Westinghouse, Raytheon, Arcturus, National Union, Marconi, Philips… The 2A3 is a directly heated output tube, that is still very popular and produce these days by various manufacturers.
The plate curves are as highly linear, but within limits of what directly heated triode can offer. Its applications are ideal for no feedback amplifiers…
Link: here.