51 Clio - Radio has no display screen, how do I enter the code?

Hi All



Apologies if this is a repost, but I've scowered the site (and the web in general) for an answer to a question like this, with no avail.



I have recently bought a 51 plate Clio Authentique. There is no radio display in the car so I am wondering if someone can tell me how to enter the radio code (I had to disconnect the battery)?



I've tried various methods of pushing buttons 1, 2, 3 and 4 the appropriate number of times, but with no joy.



Here is a picture of the radio that's fitted in the car -http://ift.tt/1jntbri



Thanks in advance for any help you can provide!