Okay, I couldn't leave well enough alone... Yesterday morning, I was working a T30 station split on 40m with the K3's Sub Rx and became a bit unnerved with the manipulation of the K3's "Sub AF" control when balancing between Main and Sub receivers. Multiple quick reaches for the "balance" function on the upper Sub AF control's outer ring was causing me to accidentally come in contact with the other controls. Looking at the K3 schematic, all four controls (Main AF, Sub AF, Main RF, and Sub RF) are all 10K in value. Even when the K3's AF control furnction menu is selected for "Normal," rather than AF "Balance," a similar issue can arrise when trying to quickly balance the Main/Sub AF controls on one shaft.
I removed the front panel to inspect the Front Panel PCB and thought a swap of the Sub AF and Main RF controls could be easily accomplished. Here's a "before" photo of the PCB area: http://216.229.20.37/images/K3-AF-1.jpg And the "after" wiring... http://216.229.20.37/images/K3-AF-2.jpg A hot glue gun can be used near the 5-pin header to keep the two ribbon cables from interfering with future front panel extractions and insertions. Now, the upper controls handles Main AF (inner) + Main RF/SQL (outer). The lower controls handle Sub AF/Balance (inner) and Sub RF (outer). When I engage split operations and use the Sub Rx, manipulating the balance between Main AF and Sub RF is easier with a bit less propensity to accidentally come in contact with the adjacent controls since: (1) the Main/Sub AF balance function is now on the inner concentric control and extends out further from the front panel than the outer concentric ring; and (2) the balance function is now moved to the bottom where the hand can approach the control from the bottom rather than directly in-line with the knob. If needed later for a sale, reversal of the mod is very easy. Certainly, this mod is not for everyone. However, I would think that in later PCB revisions, Elecraft could provide the option of selecting the existing format or the modified format at the time of purchase -- or to the builder who simply makes a few header pin changes during construction. Of course, the front panel legends also need changing and that's probably the biggest drawback to the mod. In my case, I will use new legends printed from a Brother 'P-Touch' printer -- printed with white lettering against black background tape. Font size and type is adjustable to match the existing legends on the K3. Paul, W9AC ______________________________________________________________ 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
