For full context see here: https://www.docdroid.net/XIK9pCk/img-20171020-0001-new.pdf
The sentence in question is from line 21-22, top of the second page in the PDF: テープレコーダーを使った放送に加えて、駅員が同じことを言ったりして、同じことを3回ぐらいアナウンスする。
My attempt at translation: "Adding up in a broadcast using a prerecorded tape, the station attendant says the same thing and announces the same thing 3 times."
First, I decided for 加えて to be the て-form of the verb instead of the conjunction because I couldn't make any sense of this first part テープレコーダーを使った放送に加えて without a verbal expression. I might've overlooked something, but I just couldn't find a solution for this approach.
Second, the way I translated and integrated テープレコーダーを使った放送に加えて seems kind of wrong. The following 駅員が同じことを言ったりして、 同じことを3回ぐらいアナウンスする already repeats that the same information is given (italic part) and is given multiple times (bold part). This in itself feels redundant. Then, in additon, I give the information that this information is "adding up" (stacked?) in a prerecorded tape.
If I translated the part 駅員が同じことを言ったりして、同じことを3回ぐらいアナウンスする。 a bit more creatively, I could make it into something like:
"The station attendant says the same thing and the same 3 times over." The repetition of "the same thing" in the full sentence could be interpreted as a way to mimic the repitive character of these announcements. However, if that should be the case, I'm having a very hard time to put enough trust into this interpretation of mine since it renders a good portion of the full sentence "redundant, repetitive" information...^^ (Note: I left out the additional アナウンスする on purpose in this second translation, since the intent of this translation was to show what I deem to be the essence of this construction of repetitive expressions).