Buccaneer HUD Cathode Ray Tube (CRT)

Technical Information

Catalogue No: C0415
Category: Head-Up Display [HUD]
Object Type: Module/Sub-Assembly/Component
Object Name: Buccaneer HUD Cathode Ray Tube (CRT)
Part No: CV6050
Serial No: 65978
Manufacturer: Rank Electronic Tubes
Division: Unknown
Platform(s): Buccaneer 
Year of Manufacture: 1976
Dimensions:
Width (mm):
55 
Height (mm):
55 
Depth (mm):
210 
Weight (g):
145 
Location: Archive Object Store
Inscription(s):

CV6050
KB/RCY
7637
Serial No 65978

Notes:

The CV6050 CRT is also identified as G0602-J2 and this one's cone is marked "TF838".

July 1953 saw the issuing of Naval Staff Requirement NA.39 calling for a carrier-borne strike aircraft with a large range capable of carrying a nuclear weapon under enemy radar cover and striking enemy shipping or ports. Blackburn Aircraft won the tender to produce their design which became the 'Buccaneer'.

The prototype first flew on 30th April 1958. The specification called for an Attack Sight giving navigation and weapon release information for the low level attack mode. The Air Arm branch of the Ministry sponsored the development of a Strike Sight System which was the name for the overall weapon aiming and release system. The Royal Aircraft Establishment designed the Strike Sight System and Cintel manufactured the Head-Up Display (HUD) element of it; the system was first integrated in 1958.

The Cintel Head-Up Display business was taken over by Elliotts and the Buccaneer PDU was manufactured and further developed continuing up to a Mark III version with a total of 375 systems made; it was given a 'fit and forget' title by the Royal Navy and was still in service nearly 25 years later. By successive commercial acquisitions, BAE Systems thus has a claim to the world's first Head-Up Display in operational service.

The symbology for the display was generated by analogue circuits within the "dustbin" Display Waveform Generator Mk2 Type 'A' on circular cards reminiscent in shape of an artists palette. Symbol shapes were created by the Waveform Generator and displaced by DC voltages derived from the data inputs. The system was quite advanced with the capability to drive a second display unit but symbols could only be changed by altering the circuit boards.

The unit refreshed the display at 33Hz; only just fast enough avoid flicker but the P1 phosphor if the CRT in the Display Unit fortunately had a reasonable persistence. Later Waveform Generators began to use printed circuit boards. This was one of the earliest applications of silicon semiconductors in place of thermionic valves (vacuum tubes) for symbol generation.

The Rank Cintel precision CRT had a two-inch flat-screen coated with a broadband green P1 phosphor (described as zinc orthosilicate or willemite). It used electro-magnetic deflection and permanent magnet focusing.

The tube operated with a 20kV EHT (via the L-shaped stem), a beam current of 20-100microamps and gave sufficient luminance for the symbology to be visible against background illumination of 10,000ft Lamberts (sunlit cloud) with a contrast ratio of 1.2:1. The spot size was 0.007 inch and resolution was approximately 280 lines. The CRT was warranted for about 50 hours.

The CV6050 CRT is also identified with the Rank Electronic Tubes type, G0602-J2

This CRT Housing has electro-magnetic deflection coils and a permanent magnet focusing that are used to operate the CRT. The housing has an interesting construction with an outer shell machined from resin bonded fabric composite material, like Tufnol® (giving it a brown wood-grain effect), a machined PTFE liner to hold the tube body and a spring loaded contact in the outer PTFE housing to connect the EHT supply to the CRT's final anode stem.

This unit's CRT Housing shows the focus magnet adjuster sleeve with its helical gear; this is driven by a manually-adjusted worm-wheel drive during display set-up.

Click to enlarge