Identifying unknown items
 

I'm clearing out my collection and keep finding interesting but unknown items: I know the membership has amazing powers of recognition so I'm hoping someone can recognise a few of these, starting with a module clearly dated Apr 66 by the attached cloth tag and from component date codes.

Two power devices have the Texas Instruments logo plus the date code 6621 plus two text markings W914 and 5219971 which do not appear in datasheetarchive nor in the Illiffe 1961 data book. The devices must have undergone some trauma as they read o/c from stud to leads (in either direction and up to 30V) while the two leads are a dead short. Both devices. I presume they were thyristors. The little mustard potted item is o/c between all terminals: maybe it had been a trigger transformer. Wiring is yellow PVC laced with nylon cord.

The Atlas computer dates from that time but there are no images of component assemblies except for one board. All other images show earnest people in white coats seated at consoles.

Re: Identifying unknown items
 

Next item is this Labgear Spectrophotometer Power Supply Type 115D1 from 1967. Google will tell me what a spectrophotometer is, they seem to look like an office desk laser printer nowadays so I'm not sure why they would have needed such a generous supply unit. This one has a big mains transformer which I would rate at 150W but the secondary is labelled as 7V 5A. Next to it is a choke of the same size labelled 15H 7A. On top of that generous smoothing it is regulated with two ADZ11 Ge transistors, and the o-p switched with a relay

Anyone know about these?

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This appears to be a microphone - anyone recognise what it came from?
The component tester just says 40pF. It doesn't click if I apply DC, but when I tap it I can see #10mV spikes on the 'scope
Dimensions: front flange 72mm with 67.5mm flats; connector hole 3.4mm
Text around the inner projection: No. 500D/A A.P.W.429 PAT.447777 & 447698

Re: Identifying unknown items
 

Microphone looks like it might be a carbon-granule type; try measuring its resistance with something like an AVO - expect to see a few hundred Ohms, which may vary if you shake it or shout into it.

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Thanks, tried that but it hasn't got any Ohms in it

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I know what this is - it's a PSU, professionally made and out of some equipment. It has two 85A2 voltage regulator valves and 5 BTH GJ5-M stud-mount diodes some of which have common connections but not making a bridge. The transformer says M22/390, 6.3V 1.8A, 6.3V 0.9A, 145V 120mA, 80V 45mA

Does anyone recognise what it came from?

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This has the kind of little motor used in central heating zone valves, except it's a very unusual rotation rate. So, what would want a continuous switching cycle of 9.6 minutes?

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Looking through my vintage Solid States box I find a few power amplifier devices: does anyone know the type number of this Plessey device?

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Could it be a SL403A, I've got one that looks identical in a drawer of old I.C.'s
Mike.

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If anyone is interested, see https://www.angelfire.com/sd/paulkemble/sound5d.html for an interesting article on the SL403 an other early IC power amps.
Stuart.

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Yes, that's it! I have a few unused SL403A if anyone needs a replacement

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Can someone identify these polarised 2-pole connectors? They are all marked CLANG, the male ones usually show an AM logo and REF. No. 5c/455, the female REF. No. 5C/2118

It would help me to know if they fit some equipment in my collection!

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Those 2-pin connectors look rather like the ones used on the back of AR88D receivers for the diversity-mode interconnection of the AGC lines.

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I think those 2 pin connectors were used on WW2 vintage flying helmets for the microphone and/or headsets. As an in line connector that just pulled apart.

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Thanks so much for the answers: the suitability as an easy-detach airborne connector sounds compelling. They can go in 'offers' soon

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The two-pin Air Ministry connectors were very much a general-purpose standard part, used in all sorts of applications wherever suitable.

Andy

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Thanks. My next object is a dial which mounts on a shaft with a 6BA grub screw: 25mm diameter and 5mm thick, it is engraved and enamelled black or very dark brown and looks like a ceramic moulding, but is aluminium as befits the tapped screw hole

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A few sharp taps on the bench might bring it to life.

Carbon mikes are truly 'orrible things, so bringing one back to life to life has no tangible benefit other than slaking curiosity.

David

Re: Identifying unknown items
 

The Knob disk was used on the Marconi MkIII series cameras from the middle 1950s as an indicator for preset controls. http://www.tvcameramuseum.org/marconi/mk3/bd687p25.html there are 4 presets in this drawing of the CCU R26 to R66

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The 270 deg scale suggests it's potentiometer related....