Note
Bud Radio catalog 241 (undated), p. 3.
Radio, Apr 1939, p. 75.
Based on an article in Radio, Mar 1939.
Not supplied with tubes or coils. Bud suggested using "any of the popular triodes such as the TZ-40, 35-T, 809, HK-54, HY-51, etc." Designed for Bud VCL series coils for the plate circuit, and OCL series for the grid.
Two versions;
BPA-500: 40 to 5 meters
BPA-500LF: 160 to 10 meters
References
Radio, Mar 1939.