Gary,

Not "finger trouble", but just the way logic circuits work.
There is a pullup resistor on the ACC2 IO PTT input - which makes it high unless one takes measures to short it to ground.

If you select Hi=PTT with nothing (or nothing active low) into the ACC2 jack, PTT will be asserted by virtue of the pullup resistor.

Normal operation for most PTT switches is to provide a path to ground (logic Low) when the switch is closed and an open circuit when the switch is open. In order to provide a logic high level when the switch is open, the pullup resistor is necessary.

So bottom line, the PTT input is normally at +5 volts. If you have nothing in the ACC2 jack that creates a short between PTT and ground, the level will be High - so setting the ACC2 PTT menu to Hi will activate PTT. Normal PTT is for a low (short to ground) when PTT is active, but there are other schemes that may require PTT=Hi although they are not as common.

73,
Don W3FPR

On 4/19/2014 7:19 PM, Gary Hawkins wrote:
I was setting up my KX3 for a headset and external PTT connected via ACC2 today. As I was setting the correct mic bias and PTT setting I noticed that if you set ACC2 IO Hi=Ptt the audio output is cut off. The radio does not seem to be transmitting but there was no audio. Other ACC2 IO settings act as expected. Is is a small problem or just finger trouble?

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