20 hours ago, PaulKing said:

Hi All, 

I’m new here and a fraud as I don’t install security alarms but came across your forum when searching Radiovisor. I’ve just picked up from a house clearance sale two intriguing wall mounted Radiovisor devices that seem to use infrared and I wanted to try and find out their original application. I will try and attach pictures but they are both around 6” square and 4” deep, one having a single lens and one having twin lenses. They are badged “Radiovisor” and inside have the type BA500T. They appear to be from the 1930-40 era but bear no dates. Can anyone give me any clues as to where they would have been used and what for as I’m intrigued by them? They’re going on the wall in the utility room, come what may, but I’d like to find out about them if I possibly can! 
Thanks for any help you can give!

 

Paul King, Kent

Seems GJD bought them in 2017 probably sacked everyone after that and lost all old data but you never know they might have some info for you

11 hours ago, PaulKing said:

Mr Happy, what makes you think it might be 1970’s, is it the wiring colours or the style of the components?

 

Small scale manufacture pre 1970's would probably be on breadboard ?

 

There are chunky but modern looking resistors & capitors. All components are marked in white text along Co. Name & model no.. Use of slotted screws say built up without power tools

 

A 4x4 box is very heavy duty or predated the plastic alarm cased detection of the 1980's ?

 

I've never seen one before or heard of the co

But item would have probably been in warehouse or similar & probably quite pricey in it's day

On 30/05/2024 at 12:00, sixwheeledbeast said:

 

These detectors will be probably from the 1960s, the circuit board is made out of phenolic which was obsolete by the late 1960s with most circuit boards being made from a fiberglass material. not to mention the strowger 600 type relay being used. Also those bakelite terminals.