can i pick up neighbours telephone conversations with a normal radio?

Answer 1

Only if you built a bug that transmits on normal radio frequencies. In the 80's and 90's I remember seeing kits for telephone listening bugs that ran on FM radio frequencies. Perhaps this is what you're hearing?

If you're not really hearing your neighbour's telephone conversations but would like to with a regular radio, other than bugging their phone (which is quite illegal!) would be quite complicated. For example, if they used an analogue cordless telephone, you could pick that up quite easily on a radio scanner. These use different frequencies than your FM radio does. You could build a block downconverter which takes a range of frequencies and linearly converts them down to a different range of frequencies. Let's say for example 902-922 is your input, Wide FM, and the output could be 88-108. Both 20MHz wide and your FM radio becomes your IF tuner. It would be a whole lot of work just to be able to hear it on an FM radio, but it could be done!

Answer 2

haha I've done that a few times on accident. Quite fun actually... :)