[1000mp] Re; PTT Keying Current on FT1000MKV Field

[Carl Kratzer]

N2QT said:  
 
"In building a FSK interface for my FT1000MKV Field. I was having trouble 
with the PTT, the
FSK part worked fine. What I found was that the PTT keying circuit of the 
FT1000 needed
a current sink of about 18ma which my poor little opto-isolator was not up 
to. This was in
conflict with the ops manual which indicates a current sink requirement of 
1.5ma.

(The FSK needed less than .5 ma sink.)

Am I missing something?

Mark N2QT"


Mark:  Put a 150 ohm resistor across the PTT jack on rear of radio.  This will
pull down the voltage enough for the opto-isolator to key the line.  73, Carl
K3RV.