Electronic Counter-Countermeasures 1963 US Navy Training Film MN-8811-B; F-4B AMCS Aero 1A Radar (Patreon)

more at http://quickfound.net/

Originally a public domain film from the National Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.

The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).

https://en.wikipedia.org/wiki/AN/APQ-120

Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/

The AN/APQ-120 was an aircraft fire control radar (FCR) manufactured by Westinghouse for the McDonnell Douglas F-4E Phantom II. AN/APQ-120 has a long line of lineage, with its origin traced all the way back to Aero-13 FCR developed by the same company in the early 1950s. A total of half a dozen FCRs were tested and evaluated on the first 18 F-4s built, but they were soon replaced by later radars produced in great numbers, including AN/APQ-120...

Aero 1A

Aero 13 did not have any capability for semi-active radar homing (SARH) air-to-air missile (AAM)s. 1A FCR was developed to add this capability by incorporating a continuous wave illuminator for SARH AAMs. This configuration of Aero 1A remained unchanged for later radars for F-4s all the way until AN/APQ-50...

https://en.wikipedia.org/wiki/Electronic_counter-countermeasure

Electronic counter-countermeasures (ECCM) is a part of electronic warfare which includes a variety of practices which attempt to reduce or eliminate the effect of electronic countermeasures (ECM) on electronic sensors aboard vehicles, ships and aircraft and weapons such as missiles. ECCM is also known as electronic protective measures (EPM), chiefly in Europe. In practice, EPM often means resistance to jamming...

Specific ECCM techniques

The following are some examples of EPM (other than simply increasing the fidelity of sensors through techniques such as increasing power or improving discrimination):

ECM detection

Sensor logic may be programmed to be able to recognize attempts at spoofing (e.g., aircraft dropping chaff during terminal homing phase) and ignore them. Even more sophisticated applications of ECCM might be to recognize the type of ECM being used, and be able to cancel out the signal.

Pulse compression by "chirping", or linear frequency modulation

One of the effects of the pulse compression technique is boosting the apparent signal strength as perceived by the radar receiver. The outgoing radar pulses are chirped, that is, the frequency of the carrier is varied within the pulse, much like the sound of a cricket chirping. When the pulse reflects off a target and returns to the receiver, the signal is processed to add a delay as a function of the frequency. This has the effect of "stacking" the pulse so it seems stronger, but shorter in duration, to further processors. The effect can increase the received signal strength to above that of noise jamming. Similarly, jamming pulses (used in deception jamming) will not typically have the same chirp, so will not benefit from the increase in signal strength.

Frequency hopping

Frequency agility ("frequency hopping") may be used to rapidly switch the frequency of the transmitted energy, and receiving only that frequency during the receiving time window. This foils jammers which cannot detect this switch in frequency quickly enough or predict the next hop frequency, and switch their own jamming frequency accordingly during the receiving time window. The most advanced jamming techniques have a very wide and fast frequency range, and might possibly jam out an antijammer.

This method is also useful against barrage jamming in that it forces the jammer to spread its jamming power across multiple frequencies in the jammed system's frequency range, reducing its power in the actual frequency used by the equipment at any one time. The use of spread-spectrum techniques allow signals to be spread over a wide enough spectrum to make jamming of such a wideband signal difficult...

https://en.wikipedia.org/wiki/McDonnell_Douglas_F-4_Phantom_II

The McDonnell Douglas F-4 Phantom II is a tandem two-seat, twin-engine, all-weather, long-range supersonic jet interceptor and fighter-bomber originally developed for the United States Navy by McDonnell Aircraft. It first entered service in 1961 with the Navy. Proving highly adaptable, it was also adopted by the United States Marine Corps and the United States Air Force, and by the mid-1960s had become a major part of their air arms.

The Phantom is a large fighter with a top speed of over Mach 2.2. It can carry more than 18,000 pounds (8,400 kg) of weapons on nine external hardpoints, including air-to-air missiles, air-to-ground missiles, and various bombs...