The Cobra MT975 walkie-talkie radios had a special "baby listener" mode, which made use of the MT975's "VOX" (voice activated transmit) facility.
The Cobra MT975 walkie talkie is no longer made, but most similar consumer-style walkie talkies will have VOX and so could be used as a baby listener.
We do not sell this type of radio any more, but they are easily available on Amazon.
And as an added bonus, unlike a specially-made baby monitor which only has one purpose, of course you can use walkie-talkies for other things as well.
When you go on holiday with your baby or young child, you often want to be able to visit the hotel restaurant after the kids are in bed, but still have the piece of mind that comes with knowing that you will hear them if they awake or cry.
With these walkie-talkie radios in "baby monitor" mode, you can leave one radio in your hotel room, or holiday apartment, while you go and enjoy an evening meal or drink several floors away, and you will still be able to hear if your children need your attention.
Radios have enough range to work through several hotel floors, and beyond.
The walkie-talkies' baby listening feature does not transmit continuously like an actual baby monitor, instead it is triggered by sound above a certain adjustable level - so when the child starts to cry, the radio transmits the sound to the receiving radio.