I calibrated it for the upper edge of the AM band, 1600 to 1700 KHz and it worked really well before with the calibration done in this range. For some reason with calibration done in the same range it is not working at all suddenly. I have never exceeded the specifications for transmitter input power being very careful about where I set that for a transmitter under test and I have followed the directions for calibration exactly including some extra steps which would be useful the ISOLAT and THRU calibration steps to be exact. It is just confusing to me why this would suddenly happen.
