Note
HDP-242 (Astatic model 997HL)
The HDP-242 first appeared just prior to the SS-9000. It features a molded beige Cycolac (plastic) case and was described as a cardioid design with a 20 db front to back ratio and a frequency response of 150 Hz to 15 kHz. It also featured switch-selectable high or low-impedance.
Photos, general information and specifications from "Heathkit: A Guide to the Amateur Radio Products," by Chuck Penson, WA7ZZE. Used with permission.