https://torontodawah.com/the-ruling-on-raising-the-hands-when-making-takbeer-with-one-hand-and-holding-the-microphone-with-the-other-hand-shaykh-ibn-uthaymeen/
The Ruling On Raising The Hands When Making Takbeer With One Hand And Holding The Microphone With The Other Hand - Shaykh Ibn Uthaymeen