Jump to content
DOSBODS
  • Welcome to DOSBODS

     

    DOSBODS is free of any advertising.

    Ads are annoying, and - increasingly - advertising companies limit free speech online. DOSBODS Forums are completely free to use. Please create a free account to be able to access all the features of the DOSBODS community. It only takes 20 seconds!

     

  • 0

What is this old electronic component?


Loki

Question

Possibly one for @Transistor Man...

Backstory:  Walking locally, they have put down old bricks below sandy paths to keep them from wearing.  I was walking back to the truck and saw a shiny square of silver coloured metal, it was hardly even above the surface, almost 2D.  I got a hammer and bolster, and excavated it.  I was hoping it was a lump of silver someone had encased in a wall, that got crushed along with the bricks and laid down however many years ago.  You can tell from the bricks they were from 'nice' houses, we're not talking new build Flettons here

So I dig the thing out and turn it over...and it's just an old electrical box, with the shredded remains of some red and black PVC cable sticking out the top. I guess it was still bright silver from being rubbed by sand as people walked over it. 

The lid was smashed, with the remains of a heavy duty foam gasket too.  What I could not understand was what was inside.  There were two sheets of glass with blue and green film in between them.  It had clearly been made and taped together (I removed one piece of tape to open it up).  I assumed it was just to cover the hole, but why would you do that with glass etc rather than a bit of old metal.

Then I realised a while after - it could be some form of early wall light!  It was designed to be mortared into a wall, and the light shone out through the hole.  It ended up getting run through the crusher along with the bricks.

There was one strange little electrical thing left in the remains of whatever it was.  I have no idea what it is.  You can see the remains of two contact pins on the blue side.  The side that looks orange, was originally covered with silver paint that flaked off easily - some sort of reflector for the light source, to shine it out the blue side?  The side on pic shows the remains of the silver paint.  It is the size of a small coin battery, not the big CR2032 ones 

The pic of the box shows the glass slides in place as I pulled it out of the ground.

I've been pleasantly intrigued by the whole thing xD

 

1242715139_BOX-Copy.png

CELL BOTTOM.png

CELL TOP.png

CELL SIDE.png

SLIDES.png

Edited by Loki
  • Cheers 2
Link to comment
Share on other sites

11 answers to this question

Recommended Posts

  • 0
1 hour ago, Chewing Grass said:

I'm only guessing at everything - I couldn't see how the original design was sealed from water ingress for example, unless it was behind a glass brick.  Looks like if it was, it would be a taxiway edge light!  But it doesn't look big or bright enough?

It is just up the road from a small private airfield though, so who knows?

Link to comment
Share on other sites

  • 0
1 hour ago, Transistor Man said:

 

Cheers! Looks pretty conclusive.  I have no idea why it was painted over...although I wonder if it was originally mounted elsewhere (The missing part of the lid?) and there was a now missing light source that shone out through the coloured films.  I can't see it being very bright with old tech lights.  Oh well, the answer is lost in time now!

Link to comment
Share on other sites

  • 0
2 hours ago, Transistor Man said:

Amazing!! I think you might be right, it looks like they wanted to filter the incoming light to some extent. (What I thought was a colour filter for an outgoing light - which with old style filament lamps would have made a lot of heat in an enclosed box)

 

  Cheers for looking into it!

Link to comment
Share on other sites

  • 0
Posted (edited)
On 25/04/2022 at 21:07, The Bear of Doom said:

It looks like an ORP12 light dependant resistor to me:

http://pmcomponentsnos.co.uk/epages/950003165.mobile/en_GB/?ObjectPath=/Shops/950003165/Products/ORP12&Locale=en_GB

I would guess that the box was the receiver unit for some kind of break-beam security alarm or similar.

 

How did you even narrow it down to the type? It's even blue! Well done, thanks :Beer:

I assume they don't run at mains voltage?

Edited by Loki
Link to comment
Share on other sites

  • 0
The Bear of Doom
32 minutes ago, Loki said:

How did you even narrow it down to the type? It's even blue! Well done, thanks :Beer:

I assume they don't run at mains voltage?

I remember using them at High School :) I've still got a few knocking around somewhere as well. As it is just a resistor it can be used at high voltages as long as the current is limited through it so the power rating is not exceeded. I would have expected some other circuitry in the box, but there doesn't seem to be any provision for installing a small circuit board.

I'm still intrigued by the blue filter on the front of the box - whatever the units purpose was, they didn't want it to respond to light at the blue end of the spectrum.

  • Informative 1
Link to comment
Share on other sites

  • 0
2 hours ago, The Bear of Doom said:

I remember using them at High School :) I've still got a few knocking around somewhere as well. As it is just a resistor it can be used at high voltages as long as the current is limited through it so the power rating is not exceeded. I would have expected some other circuitry in the box, but there doesn't seem to be any provision for installing a small circuit board.

I'm still intrigued by the blue filter on the front of the box - whatever the units purpose was, they didn't want it to respond to light at the blue end of the spectrum.

An infra red break beam?  Or is infra red beyond its range?  Maybe a red laser?  I've seen those used for fire detection...

We'll never know but I am still convinced it comes from the remains of what was once a very nice country house, so I think you guys are right it's some sort of old detection thing

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Answer this question...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...