On March 12th an Iranian F-4 jet flew towards an American MQ-1 Predator patrolling the Iranian Gulf coast. The MQ-1 was in international waters (more than 22 kilometers from the Iranian coast) and it was feared that the Iranians were going to try and shoot it down. The Iranians had tried this before and may have actually shot down smaller American UAVs that were near their border in the past. Last November an Iranian F-4 fired two missiles at an MQ-1 in a similar situation, but both missiles missed and the F-4 turned away rather than try an attack with cannon. The U.S. told Iran that there would be repercussions if they tried that again.
During the recent incident two American jet fighters were nearby, apparently in case Iran tried to attack American UAVs again, and told the approaching Iranian F-4 that it would be attacked if it got any closer. The Iranian jet turned away and was never closer to the UAV than 25 kilometers. An Iranian F-4 would not last long against any current American jet fighters.
Iran bought 225 F-4 Phantom jets in the 1970s, and several dozen are still operational. Spare parts are obtained via a smuggling network, with some of the less complex parts manufactured inside Iran. Of the 5,195 F-4s manufactured, some five percent are still in service. It's a 1950s design that, for its day, was quite advanced. The two seat, 28 ton F-4 is still a credible fighter bomber, able to carry eight tons of bombs and missiles. Normal combat radius is about 700 kilometers. The average sortie lasts about two hours.
Given the shortage of spare parts, the Iranians want to keep their remaining F-4s on the ground as much as possible. Moreover, a lack of refineries means Iran has to import most of its aviation fuel. To solve this problem, Iranian engineers designed and built flight simulators for the F-4. These entered service in 2008.
The first Iranian F-4 simulator cost about a million dollars to develop and build, and it apparently used a lot of off-the-shelf hardware and software. With that approach, and an F-4 cockpit wired into a PC running the whole thing, you could create a credible simulator for really cheap. Large screen flat panel displays and high end video cards can provide a reasonable approximation of the dome type displays used in high end Western simulators (which go for $40 million and up).