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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