DAX TX with hardware PTT

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I'm having trouble sending voice to my 6500 via the DAX TX channel while using a hardware PTT switch.  VOX and MOX work fine  But, the hardware PTT switch seem to only key the physically connected mics.  I can see that making sense in many cases, but it's not what I'm looking to do.  Am I missing something?  The interface to SDRCat has me thinking that I can map a hardware serial port to an SDRCat PTT port but I'm not at all sure it means what I think it means.  
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K1DBO

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Posted 3 years ago

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Mark - WS7M

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I had a similar question asking if the PC input could be keyed with a footswitch. It is actually disabled and I think DAX would be too for some reason. Tim explained it but I think it needs to be reconsidered.
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Barry N1EU

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The only thing you're missing is a previous recent thread that discovered the same thing.

Barry N1EU
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K1DBO

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As it turns out... you can use a hardware PTT to key the DAX TX channel.  It might even work to key the PC remote input as well but I didnt test that.  I just used SDRCat to map a hardware (existing) serial port on the computer as a PTT port.  Then, I put a cable together to short a couple of pins with a footswitch, yada yada, footswitch now  keys DAX TX.  

I was expecting to short pins 5 and 7 to make this happen.  Maybe I did.  But my meter seems to be telling me I'm shorting pins 7 and 8.  I'll take a closer look for crossed wires later.  But for now, everyone can rest easy knowing they can use a footswitch.

While it would be nice to use the hardware PTT inputs on the radio itself, this solution only requires a simple cable and even allows taking the footswitch to a remote computer.

Now if I could just get the footswitch to enable/disable VOX instead... but that might take external software.

...of course this was probably already mentioned in a previous post too.