AI Mark IV Radar (Stock Device slot 232)

[el cid again]

For reasons unclear this device is given a range of 30 (thousand yards)
instead of 6.

SCR-540 1.5m Radar

American Version of British Mk IV Radar. Manufactured by Western Electric, delivered 1942 for installation in USAAF P-70 (right) and Marine Corps PV-1 (lower right) night fighters. First confirmed combat kill April 19, 1943, 6th NFS, Guadalcanal.
Description
1.55 cm airborne radar for aircraft interception. Weight: 181 lb including cables and inverter. Operators: 1. Power: 40 amp, 27 volt DC. Antenna: fixed quarter wave dipole with directors on side of fuselage (azimuth receiving): 2 fixed quarter wave rods, one above and one below wing (elevation receiving). Indicators: 3-inch CRT with vertical baseline target pips on left and right (azimuth): 3-inch CRT with horizontal baseline, target pips above and below (elevation).

USMC PV-1 night fighter of VMF(N)-531 at Vella La Vella, Solomono Is, 13 Jan 1944Research and Development By
British and Bell Telephone Laboratories



Performance

Max. Range on: Bombers, at 20,000 ft: 6000 yd.
Fighters at 17,000 ft: 4000 yd.
Minimum range: 300 to 500 ft
Range Accuracy: 300 yds.
Angular Accuracy: 10° Elevation 10°



Search
Fixed antenna, targets within forward hemisphere 160° elevation sector may be detected. Effective search range limited to altitude of plane.
Antenna Specifications
Transmitting: Bent folded dipole with director on nose of aircraft. Elevation receiving: 2 fixed quarter wave rods with directors, one above and one below the left wing. Lobe switching at 1750 cycles per minute.
SCR-540 elevation antenna, transmitting antenna, and azimuth receibing antennae on wing of A-20

Anntenna installation on A-20 (prototype P-70), left-to-right: elevation receiving antenna, transmitting antenna, azimuth receiving antenna.

Transmitter Specifications

Frequency: 193 mc/s Pusle Rate (pps): 750 to 850
RF Source: 2 710s push-pull Pulse Rate Beacon: 750 to 850 nps
RF Lines: Coax (solid dielectric) Pulse Legnth: 1.3 µs
Pulser Type: Hard Tube Pulse Length, Beacon: 2.1 µs
RF Peak Power: 10 kw Energy pp, Radar: .013 joules
RF Average Power: .01 kw


Receiver Specifications

Type: Superheterodyne IF Band Pase: 5 mc/s
Stages: O-RF; 4-IF Mixer: 955 tube
Local Oscillator: 955 Noise, db above kt df: 14-16
Intermed. Freq.: 30 mc/s



Indication and Data Output
Operator has indicator with two 3-inch CRTs. Left tube has horizontal sweep with echoes appearing as pips above and below searching plane. Right tube operates similarly but has a vertical sweep with left and right pips indicating whether target is to the left or right of searching plane. Time scales are variable and the distance for a given length of trace depends on control setting. Scale is exponential. Attack range: 1-7 miles. Homing range: 100 miles.



Remarks
Maximum altitutde for satisfactory operation: Approximately 20,000 ft. Operates with SCR-640 homing beacon.
Generally not employed to control an area when prsence of enemy aircrft has not been determined in advance. SCR-540-T2 is similar to SCR-540-A except for minor circuit differences.

[YankeeAirRat]

Lots of data there, however your information is not correct. The Mark IV (or Mark 4 for those of you who don't read Classic Roman) was first used during the Battle of Britain where Beaufighters Mk.1 were equipped with the Mk.IV radar to help intercept the German night time bombers. Reference Link is from the RAF Museum Online research
Oh and the full data on the Mark IV from a manuals website, In a PDF format. The data for the Mk.IV is on page 11.