Mullard ORP12 LDRs

[Kipper4]

So Today I visit my local pops electronic sore for some AC152 germanium transistors(AC128 replacements).
At that price Sir I'll take twenty. Thank you very much. I digress.

I asked if he has any ldrs just out of intrest.
"No sorry son. (which feels kinda wierd since I'm 50) But I have something to show you."
He hands me two plastic tubes and says "Try these. You will need to open them up and get the Mullard ORP12 out. I got them from an alarm system. See If they're any use to you. If you like them I'll give you a good price on them next time you come."

So I've googled it and found a bit of info but not too much.
Mostly Silonex stuff and I'm not sure its the same thing.

So the question is.
Have you come across these/ used them?
Thanks
Rich

[armdnrdy]

http://www.datasheetarchive.com/dlmain/Databooks-5/Document21528.pdf

[duck_arse]

get em. the first part I ever owned, my memory may be faulty, was an orp12. went with a 555 to flash some leds, speed varied w/ hand waving.

what are the NSL3 that appears on your schems, kipper, I can't find data for them?

[Kipper4]

Thanks Larry that's one of the sheets I found and 2.4k nominal is pretty low.
Nsl32s Duck Arse thanks too see here

http://www.farnell.com/datasheets/16352.pdf

When I'm done testing the Germs. I'll do some light/dark testing

A quick test says 5-10k dull daylight
5meg dark

[duck_arse]

those say 500R - 500k, so they should be perfeck for the junk we been working on lately. unless you gots the led connections backwards. the 220k resistor across ldr will show signs I'm sure.

on those alarm system parts. I used to work for chubbs, dipatching parts for bank installs and such. we used to import frum england, cause we aussies were so imcompentant, units called burgoguards, in a variety of models. they mounted on vault doors and walls and "detected" things to trip the alarms. one model could be fitted with an LDR, which was called "ORP", for some reason, just in case the blagger turned on his torch.

I still have my ldr, an NSL-447, and it is HUGE! 25mm across or so. very nice. and the steel burgoguard box would be just about pedal perfect, from memory. just now I think they mighta just used an internal ldr for when blagger opens the alarm-panel door and peers in w/ torch, so you'd end up with a real big hinged-front steel box. something to ask the geezer next time you see him.

[Kipper4]

I will try the ORP12 jst for kick and also the other ldrs you reckommended DA thanks
As for the ORP they were contained in a lght resistant tube (Black plastic 3/4" Dia about 4" long) with a bung in one end with a hole in it and the LDR was at the other end attached to a 3 pin DIN plug. Which makes me think it ad a light source pointed at it permanantly and was a brake to make kinda deal.
Which If my theorem is right is also unfortunate because from why I've read the leds become unstable after prolonged exposure to light.
Hmmmmm
we will see.
No further progress on the junk as Its flat out, Knackers nailed to the wall at work, as soon as I can I'll be all over it.
Cheers