Thanks, Don. I did check that, and redid all of T1’s solder joints. No change. I was about to rewind T1 altogether when I decided to check the archives. Using a search method earlier suggested by Phil, W7OX, I found a post by you in 2013 answering the very same question. On reading it something struck me — the person posing the question recited that he had set the process up by, among other things, turning both R1 and R2 fully clockwise. That hit me — I had read that instruction as full COUNTER clockwise! I checked the manual again, and there it was - full clockwise. So, after doing that the right way, and suffering some chagrin, all was good. The U4 pin 1 voltage is a bit low at 2.8, but the null voltage gets down to 006 using C55 as prescribed.
What you just wrote would have been exactly right - if I hadn’t been so d*****d stupid. Thank you for not thinking that I could have been. “RTFM” is now amended to read “RTFM-C” where C = carefully. I am posting this on the reflector by way of self-discipline. If I didn’t confess it publicly, I’d be less likely to learn from it. Thanks, as always. Ted, KN1CBR On 5/7/16, 12:24 PM, "Don Wilhelm" <[email protected]> wrote: >Ted, > >You will find the problem is with T1. It must be wound and installed >exactly as shown in the manual, and that includes the direction of the >winding. > >Your K2 is likely putting out all the power it is capable of, so do >those TUNEs for only a short period or you will be replacing the PA >transistors. > >73, >Don W3FPR > >On 5/7/2016 12:02 PM, Dauer, Edward wrote: >> Advice requested for the following problem: >> >> Completed and installed the KIO2. That works fine, so far as it has >>been tested with the outboard ("twins") KPA100 and KAT100. Next step >>was to put the amp and high power tuner aside and install a KAT2 in the >>base K2. [In case it matters, the K2 does not have the battery option.] >> >> All went well with the KAT2 until the Bridge Null Adjustment. There >>are two strange symptoms: >> >> First, adjusting C55 has no effect, and the display does not behave as >>it should. When Tune is held, the display first says HiCur, then it >>quickly changes to ATU and then, again quickly, it changes to 000 and >>stays there. Adjusting C55 to every possible position changes nothing. >>Each try produces the same display: about 2 seconds of HiCur, two >>seconds of ATU and then 000. >> >> Second, the DC voltage at pin 1 of U4 is way off. In Receive Mode it >>reads 0.0, as it should. But in Tune mode, at 5 watts indicated, it >>reads only 0.69 DCV rather than the 3.0 to 4.0 expected. >> >> I haven't put an external power meter on the rig yet but a 15-watt >>dummy load gets warm after a while so there does seem to be RF output. >> >> I see no solder bridges, no cold joints, no breaks or shorts thatI can >>see. The plugs and sockets have been checked at least five times to >>assure they are properly aligned and properly assigned. >> >> Any ideas, anyone? Thanks! >> >> Ted, KN1CBR >> ______________________________________________________________ >> 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] >> > ______________________________________________________________ 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]
