OK, new test results, followed by an inexplicable resolution to the problem!
I'm comparing the two elecraft-specific DB15 cables here, with the suspicion that one of them is broken or defective. 1. *Physical observation* The K3/KPA cable has all pins present. The KPA/KAT cable has pins 1, 6, 7 missing. But it looks deliberate, and those pins are not used anyway (according to documentation.) I do not see any bent pins on either cable. 2. *Communication directly between radio and amp* When I connect the radio and amp directly together using the K3/KPA cable, three things work: - the amp follows the radio's band-switching. - placing the amp in OPER causes the radio to print 'KPA500' on the screen. - keying and amplification works properly. When I connect the radio and amp directly together using the (slightly suspect) KPA/KAT cable: - the amp follows the radio's band-switching. - keying and amplification works properly. The only unusual thing here is that switching to OPER causes no message on the K3 screen. 3. *Communication with tuner as 'middleman'* When I connect the K3/KPA cable from radio to tuner, and connect the KPA/KAT cable from tuner to amp, things don't work. The radio and amp do not communicate at all. When I *reverse* the two cables above, *everything works perfectly.* 4. *Conclusions* - The cables are supposed to be wired identically, and yet they behave differently. - My problem is now solved, and I don't know why. :-) ______________________________________________________________ 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 Message delivered to [email protected]
