what is the meaning & origin of the sufics "ics" as used in Electronics etc.?

Answer 1

The main suffix you are interested in here is the "-ic" to which the "-s" was later added.

The -ic suffix came into Middle English from Old French (-ique). The French suffix was descended from Latin -icus, and the Latin was most likely originally borrowed from the GREEK suffix -ikos (though some suggest the Latin was original, a relative of the Greek form, not a borrowing of it).

The meaning of the suffix is "pertaining to; of the nature of, like"

On the history see
http://en.wikipedia.org/wiki/-ic

And here is something about the Greek suffix:
http://www.wordinfo.info/words/index/info/view_unit/1029

The addition of -s is often used to turn an an -ic adjective into a noun, often one referring to a FIELD of work or study (things pertaining to the subject referred to in the root word)- mathematics, linguistics, academics

Answer 2

This is not a suffix. It is an "S" added onto the word electronic. Just like in Tectonics. It is the word tectonic with and "S". A suffix would be "est" on the word biggest to show that it is the biggest one there is. Just like fastest to show it is the fastest one there is.