So...I'm going to show stupidity here. Nothing new...so bear with me, please. Anyway...looking to use the DMK dongle to key a radio whose PTT is a simple key to ground. Think normal HF or vhf rig like a 7900 or even a KenYaeCom HT, where the ptt basically closes a circuit. Hooking up a meter between ground (pin 20) and pin 1 (PTT) on the DMK, and issuing a command to key the dongle gives me close to a 0 ohm reading, but not quite; still at about 10 ohms. (and I know how to hook up a meter...fwiw, it's a simpson 260, not a digital, so, I can see the needle swing...). This obviously is not what I'm looking for. Yes, I know what the circuit is rated for (not much) and it's an open collector... So, the question is...is this pin basically a contact closure (which IS what I'm looking for), or some other logic level that I'll have to convert? If so...any pointers or ? I freely admit that digital logic (or lack thereof...) especially at this level (pretty basic, huh?) escapes me...but am willing to learn. TIA. Bryan WB0YLE Allstar 27294/27295 Echolink WB0YLE-R