Still alive (AT-11)
Wow, unexpectedly my AT-11 is still alive. I had thought the MCU malfunctioned, because after a few years the tuner ceased to tune properly and its idle current consumption was a bit too high. I had already given up hope and started to create a small board with a different controller, but resoldering of a few spots and readjusting the SWR bridge helped. The culprit for the high current seems to be the crystal oscillator, it gets warmer than it should. In case you do not find the AT-11 on the LDG website : It is a discontinued model , probably one of their first (the first?) products.
Mine is even a relatively early version within the AT-11 series, I only saw one manual with a photo of a PCB probably predating mine. Looking at its inner life, you may notice that LEDs and switches are not mounted on a daughterboard like shown in the final AT-11 manuals. You will also not see the shift register used later, here the MCU still controls all relays directly.
I bought this as a kit back in the 90s, something not possible any longer. It was fun to build and now serves me again pretty well. I am planning on putting this onto the roof (in a suitable enclosure, of course), so I had been toying with the idea of making a remote cable. But then I found a very simple solution for activating the "Tuner" button on my IC706mkII. (no "G", unfortunately). The 706's manual explains every pin of every socket on the transceiver, with one exception: The tuner jack. Luckily, I found W4INF's article regarding an external tune switch and built one. I still do not know the exact requirements and functionality of each pin, but now I can get the 706 to tell the tuner to do its job, with 10W in CW, regardless of power or modulation settings.
There are problems though, at least with my 706mkII: After using the external tune switch once, the transceiver will initiate tuning on every band change. Also, to deactivate this function, I need to press the transceiver "Tuner" button twice shortly, different from what the manual says.
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