These are the mods which I found on internet, but what do they do or
mean?


These are all pretty common mods that are popular in several ways,
You have a very nice rig there.
the flickering of the channel display would indicate a cold solder joint on the
channel selector board if when wiggling the knob it goes off and on.
Unless you have done soldering before, I would not reccommend veturing into
this on your own.
Enjoy the radio...

**** Life Is Too Short...***
****Enjoy The Ride...***