Relic Information query matches
Matching on query: Unique id = 33/97, Name = any, Associated machine = any, class = any
Unique id/year of acquisition: 33/97
Name: Ring repeater
Other nos on object: none
Inscription: Repeater Mk.3 Serial No.01 (on sticker), Good spare 20/5/85 (on sticker)
Description: Grey metal box with brown Bakelite (?) edges. One edge has 1 15-way D-type plug and a few other holes. At one end of large face is a 16-way plug. PCBs visible inside through gaps in casing.
DW: These are 2 components of the Cambridge ring. They were repeaters. The Cambridge ring consisted of a pair of twisted wires which were taken round the Lab and they plugged into one of these devices. This device would regenerate the pulses and allow some device which accepted or gave information to be attached to the ring. A particular ring would have up to 256 different repeater elements and each was numbered and it used the packet system whereby a packet held source number, destination number and 2 bytes of information plus about 5 control bits which indicated the starts of packets and various other information, whether the packet was full or empty and so. These were designed in the Lab but they were wire-wrapped by an outside firm and the construction inside is small scale integrated circuits where the circuit containing at the most about a 4 bit shift register which could be loaded parallel- or serial-wise and if I remember correctly there is about 40 or 50 such circuits in one these boxes. In addition there were some straight forward transistors for generating the power supplies inside from the ring itself and for detecting the incoming pulse and converting it and generating the clock. These were in use a number of years. In fact I believe the last one to be used is supposedly at the University of Hertfordshire which was disconnected 2 or 3 years ago. So they had a fair life.
Q: When were they first used/ first designed?
DW: They were first designed 1978. There was an old version which used the package injection technique. These were modified ones which allowed for easier maintenance and automatic diagnosis of faulty repeaters These were ones which we standardised on throughout the Lab. It became a UK standard and supplied to many universities throughout the UK.
Q: You say they were designed in the Lab - who was responsible for that?
DW: I designed these - though to some extent it was collaborative for various design decisions taken in collaboration with other people. But the individual design of this and of course of computers as design automation for generating the wiring which was sent to outside suppliers who used automatic wire-wrapping machines which were then available.
See also: 32/97
See also: 101/99
See also: 111/99
Number of matches = 1
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