HAVE DOUGHNUT-Tactical (Vol II) (published 1 August 1969, declassified 23 Mar 2000, and released publicly 29 October 2013 through the George Washington University's National Security Archive) discusses the APQ-72 (F-4B), APQ-109 (F-4D), APQ-120 (F-4E) and AWG-10/APG-59 (F-4J) performance vs. the MiG-21.  Some summations:

The APQ-109 acquired the MiG-21 on average 5-10% further away possibly due to the difference in beam width and redesigned radar reflector. 

apq-109라도 mig21보다 평균 5~10% 멀리서 포착 가능

Head-on co-altitude, average detection was 20NM with an average lock-on achieved at 15NM. [1]

Head-on시에 평균적으로 20nm의 탐지와 15nm의 락킹 능력을 가짐

Tail aspect detected at 25NM and tracked at 17NM on average. [1]

Tail aspect일때 25nm에 17nm

Abeam, detection averaged 35NM and tracked at 28NM. [1]

3-9일때 35nm에 28nm(펄스도플러랑 다르니까.. 표적이 빔일때 오히려 면적이 크니 잘 보임)

Ground clutter at lower altitudes complicated the radar tracking problem.  Both the APQ-109 and APQ-120 were practically blind looking down, and using the auto-acquisition mode in a look-down scenario is also not useful as it only sweeps 12,500 feet, leaving no-time for a forward quarter shot. [2]

ㅇㅇ 룩다운에서는 거의 장님임

The F-4B's APQ-72 performed comparably, but aspect was not provided:

5-15K Feet saw a max detection of 32NM, and an average 20-25NM.  Track range maximum was 18NM and average 15NM.  [3]

15-30K Feet saw a maximum detection of 40NM, average of 30-35NM.  Track range was 27NM max and 25NM average.  [3]

The F-4J's APG-59 fared far better in Pulse Doppler modes; apparently the pulse mode was worse at high altitudes.

The APG-59 averaged 45NM forward-quarter detection with a maximum range of 62NM, and on two occasions, the F-4J spotted the MiG-21 immediately upon takeoff from 15K feet (look-down), detecting, acquiring, and tracking by 50NM. [4]

There's some things to keep in mind, of course; I have no idea how they tweaked the APQ-120 (if at all) from 1969 to the mid-1970s (roughly the period the first F-4 Headblur releases is supposed to be representing); the document mentions an expanded auto-acquisition mode to 30,000 feet would be desirable, but this still doesn't change the limitations of a pulse radar looking down, and I don't know if "desirable" became a requirement and actually happened..  Also, if the F-4E is coming with AIM-7Es, it's good to have SA earlier on, but your engagement range is still less than the average head-on tracking range of the APQ-120.  Also, although this shouldn't need to be stated, a large fighter or a bomber would be seen further away.

Suffice to say, I don't plan on being able to see a MiG-21 rooting around in the dirt from long ranges, at least until a model with a PD radar is released.

J형은 펄스도플러 레이더 가지고 있으므로 논외

Have donut에 나오는 이야기.