Is it legal to make a radio transmitter?

 

Certain frequency bands (depending on the country you are in) are available for amateur use without a licence, but most bands are highly regulated and it would be illegal to transmit in those bands without a licence.

 

It isn't just the frequency band but the transmitter power too. This describes the UK position on short range devices.

 

Hello,

You will have to apply for a licence in pakistan (based on the used IP).
http://jamilandjamil.com/?p=1050
http://www.prometheusradio.org/Apply_LPFM_License
This was found using the following query:
pakistan licence "radio transmitter"

Bertus

 

Not only power and frequency but also how much bandwith you use, riding on the nominal frequency. Keep in mind that splatter on adjacent bands IS a concern.

Just in case, try to start with low power.