HELLO ASPIRANT,
yes, of course you can give isro exam from electronics and communication brach. during the month of march 2019 isro has vacancy for electrical branch. but this was really less compare to electronics and instrumentation branch. but you need to really study hard as digital and communication, signal system, antenna and radio theory, questions comes a lot from those branches. you can get previous years questions from official websites.
Candidates can check B.Tech Cut off for Top IITs & NITs here.
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