I'm not exactly sure of the timing requirements, but sending well-formed CW at 30+ words per minute requires timer resolutions in the low numbers of millisecond range. This can be done with high resolution timers (introduced for multi-media), but you need to have the process priority right so that the program that is turning the serial port (or parallel port) control lines on and off can get control within a very few milliseconds of the desired time. Often higher priority things like disk I/O interrupt handlers and programs that are I/O intensive can keep control away from the (user priority) program doing CW long enough to cause grief. Disk I/O from paging in programs is often a higher priority task than any user-mode program.
I've seen some low-level device driver level solutions (I recall N6TV wrote one for OS/2) that can get close, but this isn't the way that the popular logging programs do it. I'd recommend a WinKey. Standalone it costs a few tens of dollars (the basic K1EL Winkeyer2 serial is only $36), and if you're into contesting at all you'll find that it eliminates a problem that can cause great consternation at really unfortunate times. I use microHAM products that incorporate WinKey chips. They work quite well for me. Dick, K6KR -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Julian, G4ILO Sent: Saturday, November 08, 2008 7:08 AM To: [email protected] Subject: RE: [Elecraft] Does K2 benefit from simple Microham interfaces? Dick Dievendorff wrote: > > My experience is that keying the radio via RS-232 control lines is > sometimes > problematic with some logging programs using a multi-tasking operating > systems (like Windows NT and its derivatives), and that problem doesn't > always show up until the log is large and you're late into the contest. > Is the reason for this that the amount of time the program spends dupe checking increases as the log grows, and this pre-empts the time critical keying process? ----- Julian, G4ILO. K2 #392 K3 #222. http://www.g4ilo.com/ G4ILO's Shack http://www.ham-directory.com/ Ham Directory http://www.g4ilo.com/kcomm.html KComm for Elecraft K2 and K3 -- View this message in context: http://n2.nabble.com/Does-K2-benefit-from-simple-Microham-interfaces--tp1473 656p1473817.html Sent from the Elecraft mailing list archive at Nabble.com. _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
