The KXPA100 has 5v on the key line and is activated by a closure to ground. Current upon closure is only about 1ma. You seem to make it sound like your radio has a voltage on the key out port, this would be unusual in modern rigs. Most rigs provide a closure to ground to key the amp. It seems likely to me that your radio is rated to handle up to 30v on the key port and a current of up to 250ma. This would mean that the rig would have no problem handling the 5v at 1ma from the KXPA100. However if the rig truly measures 30v (or actually any voltage) on the key port you would need some kind of relay or other switching circuit to provide the closure to ground to key the KXPA100.
On Wed, Jun 14, 2017 at 7:06 PM, Grady Harper via Elecraft < elecraft@mailman.qth.net> wrote: > I would like to drive the amp with a tx that shows the PTT Out line to be > 250mA at 30 V (max). Do I need to modify current and voltage from the > transmitter to the KXPA100? > The Key In pin for the amp wants 5V at 1 mA. > > AJ4YA > Grady > > Sent from my iPad > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to jimk...@gmail.com > -- Jim K0XU j...@rhodesend.net ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
