I assume that TTL-level means it works with a +5V/0V swing on input to the radio?
73, doug On 25-Sep-12 14:33, Wayne Burdick wrote: > Brian, > > The ACC1 port on the K3 is fully compatible with the RS232 standard, > although it uses 0 V rather than a negative voltage when transmitting > a low unit. This is the same TTL-level interface we use in several > other products including the XG3, W1, W2, and K144XV. We offer both > RS232 and USB cables that work with this port, and as far as I know > these cables work with all laptop and desktop computers. > > You can certainly roll your own. I'll send you the schematic of that > portion of the circuitry. > > 73, > Wayne > N6KR > > > On Sep 25, 2012, at 7:09 AM, Brian Lodahl OZ2BRN wrote: > >> Hi, >> >> I'm reposting this because I'm still struggling to get my customized >> CAT >> + CW interface for the Kx3 to work: >> >> I attempted yesterday to wire up a TTL Serial cable from FTDI, >> containg >> both CAT as well CW keying (using #RTS), and I can easily get the CW >> to >> work (keying using #RTS through a 4N25 and two 1N5711 diodes for dit >> and >> dah), but it seems that the CAT does not work with this interface. >> >> My question again: -What is the "official" Elecraft electrical >> specifications for the ACC1 interface ??? What voltage levels for Rx >> and >> Tx, respectively, with respect to GND or Positive voltage ? >> >> -Does anyone have a schematic of the ACC1 interface for Kx3 that I can >> take a look at ? >> >> 73' >> Brian OZ2BRN >> >> >> >> >> Den 21-Sep-12 08:34, Brian Lodahl OZ2BRN skrev: >>> Hi Kx3 users, >>> >>> Other posts have previously dealt with the issue that the standard >>> KXUSB >>> cable for Kx3 does not support CW keying from the computer to the Kx3 >>> radio, simply from the fact that as opposed to the ordinary serial >>> connection (old RS-232 standard), the RTS and CTS pins are not >>> available >>> in the 3.5 mm, three-pin TRS jack connector for ACC1 in the Kx3. >>> >>> Pursuing this further, and not wanting to have more than one USB >>> cable >>> to my PC from my Kx3 for all of my buisness on the PC side, I want >>> now >>> to build a new interface cable using a custom cable assembly from >>> FTDI: >>> >>> http://www.ftdichip.com/Products/Cables/USBTTLSerial.htm >>> >>> Then using either RTS or CTS flags in my PC's radio interface setup >>> (log >>> program Win-Test) to pull the CW key connection in the Kx3, >>> possibly via >>> a FET or Opto Coupler. >>> >>> - I have a 4N25 in mind for this ... with parallel coupling of two >>> 1N5711 to the paddle dit's and dah's. >>> I did the very same thing on my K2, and it worked like a charm. >>> >>> Checking the signal levels on my oscilloscope today on the ACC1 data >>> connection, I find: >>> >>> Tip connection = Rx data from the computer to the Kx3 = 5,0 - 5,2 >>> volts >>> level (generated by the FTDI line driver) >>> Ring connection = Tx data to the computer from the Kx3 = 7,0-7,5 >>> volts >>> level (generated by the Kx3 line driver) >>> both with respect to GND being the sleeve pin of the ACC1 jack >>> plug, and >>> looking pretty, noise-free and free of any transients. Good, nice >>> square >>> signals with good integrity. >>> >>> Baud rate of the data here is obviously configurable, and with your >>> PC's >>> logging program so is the polling rate of how often the PC requests >>> data >>> from the Kx3. >>> >>> My question :What is the "official" Elecraft electrical >>> specifications >>> for the ACC1 interface ??? >>> What voltage levels for Rx and Tx, respectively, and what impedance >>> to I >>> terminate with when I interface with e.g. opto coupler for my >>> project ? >>> >>> Would I be OK assuming I just use a 5-volt TTL-level cable version >>> here, >>> both ways Rx+Tx OK ? >>> >>> TTL-232R-5V: >>> http://www.ftdichip.com/Support/Documents/DataSheets/Cables/DS_TTL-232R_CABLES.pdf >>> >>> >>> 73' >>> Brian OZ2BRN >>> Kx3 # 1118, K2 # 6936 (to which I did the same mod) >>> ______________________________________________________________ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:[email protected] >>> >>> This list hosted by: http://www.qsl.net >>> Please help support this email list: http://www.qsl.net/donate.html >>> >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
