Function:

Provides transmit/receive control signals with sequenced delays, to be used by other circuits that need to be keyed

Input/Output:

• POWER: 9-15 VDC, 5.5 x 2.5mm power jack
• KEY IN: 1/8" Mono Jack
  Max Input loading (to keyer): 10K (pull-up to Vsupply)
  INput states: open = RX; Ground = TX
  
• KEY0: CMOS/equiv, RCA Jack; Low on key-down, High on key-up (raw keying)
• KEY1: CMOS/equiv, RCA Jack; Low 1 mSec after key-down, High on key-up (keys TX)
• KEY2: CMOS/equiv, RCA Jack; Low 0.5 mSec after key-down, High 0.5 mSec after key-up (keys VFO)
• KEY3: CMOS/equiv, RCA Jack; Low on key-down, High 1-50 mSec after key-up (RX muting)

Key Specs or Limitations:

Misc Notes:

Trimmer or programmable control of KEY3 delay, to accommodate unknown receiver recovery time