
Can I come in and watch him
invent the TELEPHONE?"
The Big Bang Theory Season 1, Episode 14

Almost as silly as Dr. Baker
having a TELEPHONE,
The Big Bang Theory Season 7, Episode 4

Yeah, now stand back
while I invent the TELEPHONE.
The Big Bang Theory Season 8, Episode 18

Good choice. Alexander Graham Bell
invents the TELEPHONE and calls for Watson.
The Big Bang Theory Season 1, Episode 14

(TELEPHONE RINGING)
The Big Bang Theory Season 2, Episode 7