Communication Concepts EB27A Construction Hints - Manual

CONSTRUCTION HINTS FOR THE EB27A
These construction hints for the EB27A are only to supplement the Engineering Bulletin
and are not meant to be used as a construction manual.
HEATSINK PREPARATION
A heatsink of sufficient size to dissipate over 300 watts of power should be used. The
heatsink should be marked, drilled, and tapped before construction begins on the PC
board. Using the bare PC board as a pattern, lay the PC board on the heatsink in the
desired position and mark the four mounting holes and the mounting hole for D1. Drill
and tap the four mounting holes and the hole for D1 for 4-40 screws. Then bolt the bare
PC board flush on the heatsink and place the RF transistors through the PC board so
they rest on the heat sink. Mark the mounting holes for the RF transistors. Remove the
PC board from the heatsink and drill and tap the mounting holes for the RF transistors
(4-40 screws). The heatsink can also be fitted with connectors, cover, etc. at this time if
so desired.
1