QSK Amplifier Controller

Description

The QSK Amplifier Controller is a build-it-yourself QSK controller that can be retrofitted into most existing linear amplifiers and for incorporating QSK T/R switching into a homebrew amplifier.  The full QST article entitled “Add Full Break-In Keying to Your Linear Amplifier” can be downloaded HERE.  This article appeared in the June 2015 edition of QST and includes background information, a brief tutorial on QSK design and additional construction information.  High resolution schematic diagrams can be downloaded HERE.  Just the bare printed circuit boards (main controller board & RF detect board) or a partial kit (PC boards and all components, minus the vacuum relays) can be purchased.

ERRATA:  The circuit diagram published in QST omitted the protection diodes across the vacuum relay coils.  Click HERE to download a diagram showing the hookup for the protection diodes and their part numbers.  Diodes are required to protect the QSK switching transistors from the inductive voltage spike that occurs when the relays open.  If you use the schematic diagram and parts list from this website, it does show the required diodes.