I know some of you are thinking, "not again".
I just wanted to point out that there is a description to home-brew an amp
keying circuit in the current issue (April) of QST. It's on page 48.
It can key up to +300 vdc without a relay.
If you need to key negative voltage or AC, then you have to add a reed relay
THIS ONLY ADDRESSES THE PROBLEM OF KEYING HIGH VOLTAGE.
IT DOES NOT ADDRESS THE TIME SEQUENCE KEYING YOU MAY NEED.
If you have an Eagle or Omni VII, the Model 318 is the way to go.
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