[TenTec] Corsair noise blanker and frequency display

[A R]

I received my newly acquired Corsair (not II), s/n  718, and have a couple of questions:

At cold start-up in the morning, it takes about a minute for the displayed frequency to stabilize and display the actual frequency. During that warm-up minute, all the display digits are toggling "randomly". Is this a common issue with the Corsairs? Is there a remedy?

The noise blanker is ineffective with respect to eliminating or even noticeably reducing powerline-generated noise that my TRITON noise blanker completely eliminates. Again, is this a common issue with the Corsairs. If so, has anyone developed a modification that improves the effectiveness of the NB? The TRITON's NB is so effective in eliminating at least the noise that plagues me, I'd sure like to get the same NB effectiveness out of the Corsair. The NB's of the TRITON and Corsair are architecturally the same (signal flow and conditioning), so if the Corsairs have characteristically ineffective noise limiters, my powerline-generated noise is enough of an operating problem, that I would even entertain adapting the TRITON's NB to the Corsair....as a last resort.

Allen------W7GIF