A memory test for the Electronics Wizards

[Michael GilliganParticipant @michaelgilligan61133]

This device has three leads connected to it, and I presume it to be a photocell of some sort; or perhaps a photo-switch. … but it's potted in a block of black resin, so the markings are obscured.

Does anyone recognise it, please ?

MichaelG.

Edited By Michael Gilligan on 07/01/2018 16:11:17

[Michael GilliganParticipant @michaelgilligan61133]

Can you please identify this PhotoCell ..

[Tim StevensParticipant @timstevens64731]

Black resin might mean an ultraviolet detector – ?

Tim

[Dave DanielsParticipant @davedaniels93256]

PIR sensor IC ?

One similar to this ??

https://learn.adafruit.com/pir-passive-infrared-proximity-motion-sensor/how-pirs-work

D.

 

Edited By Dave Daniels on 07/01/2018 16:52:01

[Michael BriggsParticipant @michaelbriggs82422]

Looks like a phototransistor in a TO-18 case. The lower rim of the case is visible, markings would normally be on the side of the can so it is probably an unmarked device.

Michael

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Tim Stevens on 07/01/2018 16:38:19:

Black resin might mean an ultraviolet detector – ?

.

Tim,

Sorry if I did not make myself clear … The can is potted in resin for structural purposes only; the window is not covered, it is 'looking at' a small tungsten filament bulb which provides incident illumination on a microscope.

MichaelG.

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P.S.

I don't have proof but I think this [Optem Zoom 65] microscope tube was originally part of a "Hughes-Palomar Bonder" and the resin block is part of their customisation.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Michael Briggs on 07/01/2018 16:59:23:

Looks like a phototransistor in a TO-18 case. The lower rim of the case is visible, markings would normally be on the side of the can so it is probably an unmarked device.

.

I'm not doing well today … I have a streaming cold and shouldn't really be posting questions.

The can is considerably bigger than TO-18, so is probably TO-5

Yes, the markings would normally be on the side of the can … but it's potted in a block of black resin.

MichaelG.

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For my pennance, I will measure the diameter [hopefully tomorrow]

[Neil WyattModerator @neilwyatt]

Well I'm disappointed – I was hoping for the much-loved ORP-12.

Worst come to the worst, just fill the top off a low-power, high gain transistor in the same size can. Carefully shake out the swarf and make an epoxy or similar window.

Phototransistors are/were generally very poorly characterised (i.e. the circuits should be very tolerant of different sensitivities and have ample latitude for adjustment if required).

It worked for me in the 80s so it should still work now.

Get well soon!

Neil

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Neil Wyatt on 07/01/2018 17:51:55:

Well I'm disappointed – I was hoping for the much-loved ORP-12.

< etc. >

.

To be honest, Neil, it was just idle curiosity … It probably works fine; if only I knew what it was there for !

MichaelG.

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Here is a Hughes-Palomar Wedge Bonder 

http://www.tarasemi.com/product/hughes-palomar-2470-v-wedge-bonder/

… all I have is the litle black tubular unit that their video-camera uses.

Edited By Michael Gilligan on 07/01/2018 18:16:08

[doubletopParticipant @doubletop]

I was going to make a tongue in cheek comment about a 1 pixel CCD. Then looked up the machine details to find

Optical system: Solid state (CCD) camera with Optem zoom lens

**LINK**

More to the point what is a wedge bonder used for?

Pete

[doubletopParticipant @doubletop]

Posted by Doubletop on 08/01/2018 00:19:32:

More to the point what is a wedge bonder used for?

Pete

To answer my own question it appears to be for I/C manufacture wiring the chip to the package pins

Pete

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Doubletop on 08/01/2018 00:24:11:

Posted by Doubletop on 08/01/2018 00:19:32:

More to the point what is a wedge bonder used for?

To answer my own question it appears to be for I/C manufacture wiring the chip to the package pins

Pete

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For info. **LINK**

http://cdn2.hubspot.net/hub/60069/file-20561336-pdf/Documents/guide_modern-wedge-bonding_ebook.pdf?t=1421176334789

https://m.youtube.com/watch?v=r1D9N04Gqoo

MichaelG.

Edited By Michael Gilligan on 08/01/2018 05:58:14

[doubletopParticipant @doubletop]

Micheal

Thanks for the info?

The youtube video took me back to the days when a system startup took an age. I once worked on a system that you'd have to wait 3 mins for the TWT's to warm up before you could do anything. When we were testing software you'd be switching the the thing on and off quite frequently. The 3mins always seemed like a lifetime.

So do you know what the item in your first post is and are you just testing us?

Pete

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Doubletop on 08/01/2018 00:19:32:

I was going to make a tongue in cheek comment about a 1 pixel CCD. Then looked up the machine details to find

Optical system: Solid state (CCD) camera with Optem zoom lens

**LINK**

.

At the risk of further complicating what I mistakenly thought was a very simple opening question:

The CCD camera is at the top of the black tube, and the device I want to identify is at the bottom; appended to the incident illuminator.

I haven't found a brochure for the original 'Zoom 65' but this is the updated version:

**LINK** http://opspe.com/IS/pdf/RZ65%20brochure.pdf

… which uses fibre optic illumination, via the cylindrical connector, instead of the tungsten bulb of the original version.

There's a beamsplitter/combiner in the lower end of the main tube which makes the light path co-axial with the image path, and thus provides shadowless illumination.

MichaelG.

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P.S. The little resin block is, I am almost sure, a custom component added by Hughes.

The photocell in question may do nothing more than tell the system that the light-bulb is on or off.

[doubletopParticipant @doubletop]

Posted by Michael Gilligan on 08/01/2018 06:28:41:

 

The photocell in question may do nothing more than tell the system that the light-bulb is on or off.

 

….and how bright it is to control the light level for the camera. Back to Neils ORP12 but that only had 2 wires so its probably photo transitor.

Pete

 

Edited By Doubletop on 08/01/2018 06:46:53

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Doubletop on 08/01/2018 06:24:09:

… So do you know what the item in your first post is and are you just testing us?

.

Pete,

As per my immediately previous post: I do have a reasonable assumption that the thing is just a status-detector, or a light-meter.

… All I wanted to know was did anyone recognise the actual device; so that I can find a datasheet.

I can't currently think of anything I want to use that feature for; but it's always nice to know what you've got.

… My cameras meter internally, so I'm unlikey to need metering of the bulb output.

MichaelG.

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I will post some photos of the illuminator [hopefully later today]

.

Edited to include reference to light metering.

Edited By Michael Gilligan on 08/01/2018 06:52:36

[doubletopParticipant @doubletop]

As Michael B suggested. By way of an example

**LINK**

Pete

[Geoff TheasbyParticipant @geofftheasby]

… My cameras meter internally, so I'm unlikey to need metering of the bulb output.

So do mine, Michael, but I still find it useful to have a light meter handy. Comparing light levels on solar panels, LEDs, etc., only a few quid on Doncaster market photography stall.

Geoff

[doubletopParticipant @doubletop]

Although the camera meters internally surely the subject needs to be illuminated?

I'd guess the sensor measures the ambient light level and augments it with the illuminator to achieve the optimal level for the camera. It would be too much to be left to chance that the installation of the system would be in ideal lighting conditions.

Pete

[MuzzerParticipant @muzzer]

I hate to say it but you can clearly see that there is only one bond wire going to the die. So it must be a component with just 2 connections ie not a transistor. It's possible that the package has 3 wires but one of the them may just be to the can, or simply that package only came with 3 leads, one of which is entirely redundant.

Perhaps I'm missing something?

Murray

[Michael GilliganParticipant @michaelgilligan61133]

Sorry, Geoff & Pete … I don't wish to appear ungrateful, but there's too much guessing going on.

I'm still feeling very rough with this 'flu bug, but I will try to get some general photos of the device later today.

MichaelG.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Muzzer on 08/01/2018 10:14:18:

I hate to say it but you can clearly see that there is only one bond wire going to the die. So it must be a component with just 2 connections ie not a transistor. It's possible that the package has 3 wires but one of the them may just be to the can, or simply that package only came with 3 leads, one of which is entirely redundant.

Perhaps I'm missing something?

Murray

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Not at all, Murray … You are very probably correct.

The specific device has an uncommon appearance, which is why I was hoping someone might recognise it visually.

The connections are all embedded in the resin block, but I believe that the relevant cable has three cores.

The wiring harness has a five pole connector with two cables … Two thicker cores feeding the lamp, and three thinner ones apparently going to this device.

Photos later, I hope.

MichaelG.

[Ian PParticipant @ianp]

I have probably half a dozen different opto sensors that have the same internal appearance (square sensor chip and one bond wire) but without being able to read the case marking would not know what each one was. I doubt very much that one could identify the part number of your device without reference to the original manufacturer.

Unless I missed it, you did not say why you were trying to identify it? If it is actually working then you could do you own tests with different light sources and generate some sort of response curve so that you could at least determine its operational purpose, my money would be on it being in a feedback loop with the lamp filament for constant illumination level

Ian P

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Ian P on 08/01/2018 10:57:37:

I have probably half a dozen different opto sensors that have the same internal appearance (square sensor chip and one bond wire) …

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I must have led a very sheltered existence, Ian

This is the only one I recall seeing with the chip mounted diagonally to the tab, and with the seal so close to the window.

As for why … idle curiosity

MichaelG.

[Danny M2ZParticipant @dannym2z]

The use of a photosensor used to be a sneaky way to implement a light sensitive 'anti-handling device' on a mine or a bomb, they have been around for a while **LINK**

So they make it just that bit harder to defuse if one wants to live to tell the tale to the grandchildren.

* Danny M *

[Author]

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