Devices to make sure phone is hung up

[David1961]

My mother lives alone and every now and then, after she is done talking on the phone, she does not hang it up properly. So there will be a busy signal until someone hangs it up properly. She's hard of hearing and cannot always hear the signal transmitted over the phone. So any alarm would need to be pretty loud. Does anyone know of any devices to help make sure she hangs up the phone? Was wondering if anyone had had a similar problem and how you solved it. There seem to be products available (I found the following one):

Fone Sitter Makes Sure Grandma Hung Up The Phone!

 

[cranberryjoe]

I wonder if she would do better with a cordless phone where she would press a button to end the call? No need to "hang it up" except to place it in the charger occasionally. As long as she presses the right button, no problem.