No Voltage on PTT Pin?

[C2]

When they say to NOT apply any voltage to the ptt pin for rig control, how little voltage is typically OK without risking damage to the radio?

The PTT keying circuits that use the RTS serial pin usually have around 8V and the circuits clamp that with a diode, but there is still going to be 1/2 volt.

Just don't want to blow something in the radio...

 

[WR0220]

Maybe put a bi-polar tantalum cap inline to block the voltage?

 

[C2]

That might work, but I think the radio won't key with the cap inline.

I was thinking of an opto-isolator, but it's nice to use what's already in the box.

I'm thinking (hoping) though that the small voltage that is there won't be enough to damage anything, but I'm just not sure and don't really want to risk it.

 

[6 Meters Rules]

opto- coupler , small relay w/ Low voltage coil! & dpdt or more too turn on & Off Whatever you like