Note
QST, Nov 1976, p. 127.
QST, Sep 1977, p. 127. ("brand new" but sill called HK-5)
QST, Nov 1977, p. 106. (Now called HA-5A)
QST, Mar 1980, p. 162.
QST, Feb 1981, p. 152.
QST, Feb 1982, p. 174.
The keyer is an iambic type based on the Curtis 8044 chip. It is capable of keying grid block, cathode or solid state transmitters. The keyer has dot and dash memory and insertion circuits. The built-in side- tone oscillator has front panel adjustable tone and volume controls.
By using a straight key, the unit can be used for manual keying of the transmitter or as a code practice oscillator for learning the Morse code.
Features Curtis Type-A iambic keying (no dot/dash insertion), dot/dash memory, a built-in sidetone oscillator, and dual output jacks to handle both vintage grid-block and direct/solid-state rigs.
Shipped in a cabinet that was color-keyed to blend in with the gray and silver aesthetics of late-70s and early-80s solid-state transceivers.
Note: Because the HK-5 uses a plastic top cabinet shell rather than an all-metal enclosure, it are notoriously prone to stray RFI causing "runaway" or erratic self-keying when operating near high-power HF setups. If yours misbehaves on transmit, adding a few ferrite beads to the lines usually tames it down.
