Hi Jim. Well, when this incident occurred, I was deep into working on an associated software problem and needed to quickly try the PC serial port directly. I agree with you comment about reading the manual and in fact I did so just a couple of weeks back when I acquired this unit. Unfortunately, at my age, I don't always recall 100% of what I read. Now that I have this problem, of course I remember reading all about needing the special cable
But, I disagree regarding the use of the DB9 connector on the K2. Having worked on tons of gear with communications ports, I've never run into one that purportedly used an RS232 interface, but would self-destruct if a real RS232 interface were attached. The KPA-100 manual clearly describes it as an RS232 interface and the schematic has it labeled as such. If it doesn't support RS232 voltage levels, then it isn't an RS232 interface in my book. And I know that there are devices that use a DB9 connector but are not RS232 compliant, but that isn't the issue here. In the document that Gary Surrency and Tom Hammond wrote on the subject several years ago, they clearly pointed out the need for a more prominent label warning of the possible consequences of connecting the wrong cable. Had I seen such a warning, I'd have remembered the reason for it and would have avoided the problem. At any rate, the worst result should be a failure to communicate and not the destruction of several important components in the unit. Having read many of your writings, I doubt that you'd have ever designed something with that sort of risk involved. When I get everything working again, I plan to document in detail what fails, how to determine if it had failed and what to do about it. Current documentation on that is rather lacking and I'll bet that there are scores of K2s out there with the same problem. 73, Floyd - K8AC On 8/22/2015 7:26 PM, Jim Brown-10 [via Elecraft] wrote: > Hi Floyd, > > I've owned and operated a pair of K2s, both of which I bought used. > Elecraft makes it very clear that the DB9 connector on the K2 is NOT an > RS232 interface, that it is not RS232 compliant, and that a standard > RS232 cable should NOT be used. Rather, the DB9 connector provides both > serial control AND several control functions. > > The DB9 connector is a generic part, and can be used for many things > besides RS232. It is also well known that while the RS232 Standard > defines voltage levels, MANY modern products produce far less than those > levels. > > I've owned a lot of gear in my lifetime, and the first thing I do is > open the manual, study it, study the wiring of the various connectors, > study the specs, and study the operating instructions. > > 73, Jim K9YC > > -- View this message in context: http://elecraft.365791.n2.nabble.com/K2-KPA100-RS232-interface-repair-tp7606571p7606587.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ 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
