Just for information, since the orange box update it's possible in CS:S to hide the radar completely for players
serverside:
PHP Code:
/**
* Sets the Hud flags of a client
*
* @param client Client index.
* @param flags Flag to set, use one of the HIDEHUD_ hiding constants
* @noreturn
*/
stock Client_SetHud(client, flags) {
SetEntProp(client, Prop_Send, "m_iHideHUD", flags);
}
public OnClientPutInServer(client) {
Client_SetHud(client, ( 1<<4 ));
}