The transmitter LED of the remote control is broken, will it work if I replace

[hummerjanne]

The transmitter LED of the remote control is broken, will it work if I replace it with another infrared LED?

[Buriedcode]

Most likely.  The black epoxy ones are the most common, being ~ 940 950nm.  They are available in clear packages too, as are the shorter wavelength ones, but I believe only the 940/950's are in IR epoxy, so guarantees they'll work with most recievers.

The two main criteria are peak current and emission angle.  Generally emitters have narrow angle, and recievers have a wider angle.   You can't go wrong with a good brand like Vishay, TSAL4400, TSAL6100, TSAL6400 etc..

So short answer is, yes it will work as long as you get the polarity correct 

[Kleinstein]

The choice of 880 nm or 940/950 nm wavelenght is not that critical. The 880 nm ones are slight visible (not the actual 880 nm they have a tail extending to the 700-750 nm range where it eye can still see a faint glow).  The 880 nm ones are usually also faster, but normal remotes in TVs and the like use only a moderate frequency and thus don't care. Most of the 5 mm ones are pretty similar in power.

Small angle ones can get more intensity and thus a better range..