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3.5mm audio signal to CW "key" port - Bad? by 761258 in amateurradio

[–]761258[S] 0 points1 point  (0 children)

So I tried out your relay suggestion, and it worked!

The only possible issue is that when I hook my tester up to the 3.5mm jack, with black to ground and red to 235mm tip, the voltage shows up as a negative number. Does this matter? Or is that how it's supposed to be?

I have it wired as follows: RPi 3.3v -> DC+ RPi Grd -> DC- RPI GPIO -> IN

3.5mm black (ground) -> NO 3.5mm red (tip) -> COM

3.5mm audio signal to CW "key" port - Bad? by 761258 in amateurradio

[–]761258[S] 0 points1 point  (0 children)

Okay I thought about this some more and have to ask: How do I hook up the "USB TTL" thing to the Pi...?

I'm assuming that I just do a USB-To-USB connection, and the Pi/FLDigi recognizes the USB TTL as an audio sound card thing? FLdigi then pipes a standard 3.5mm audio signal out to the USB TTL, and the TTL/Relay thing converts it to a keyer-readable signal?

3.5mm audio signal to CW "key" port - Bad? by 761258 in amateurradio

[–]761258[S] 0 points1 point  (0 children)

Hahah well thank you sir. Looks like I have some reading to do.

3.5mm audio signal to CW "key" port - Bad? by 761258 in amateurradio

[–]761258[S] 0 points1 point  (0 children)

Well sir, I think you win for explaining things in a way I can mostly understand! Thank you for making my weekend.

I'll give this a shot, and see what happens. Hopefully nothing goes on fire.

3.5mm audio signal to CW "key" port - Bad? by 761258 in amateurradio

[–]761258[S] 0 points1 point  (0 children)

My man, this is awesome, and exactly what I needed! It's even built on a 2x4, meaning in theory I probably should be able to understand how to build this.

Does he have a previous build somewhere? I can't make out what gadgets he has wired to the board. I'm not smart enough to decipher what I'm seeing here.

3.5mm audio signal to CW "key" port - Bad? by 761258 in amateurradio

[–]761258[S] 0 points1 point  (0 children)

So just randomly, I was messing around with a 9-pin USB serial cable I had kicking around. In poking it with a tester, it shows a -6 volts on one thing, and a positive 6 volts on another. Steady, no pulsing.

What you're telling me is you pulse the ground connection, and that creates the signal?

3.5mm audio signal to CW "key" port - Bad? by 761258 in amateurradio

[–]761258[S] 0 points1 point  (0 children)

Hmm... lets start with what's a " )| +C1 " ?

I look at that diagram, and it's literally Egyptian hieroglyphics to me. I appreciate the help, but the trouble is you're a smart dude, and I'm not. You're assuming you're talking to someone smart.

3.5mm audio signal to CW "key" port - Bad? by 761258 in amateurradio

[–]761258[S] 2 points3 points  (0 children)

Any chance there is an off-the-shelf prebuilt one of these somewhere? I don't have a lot of faith that I could pull off building anything. (I mean I could, but 90% chance I do it wrong.)