Wireless Set No. 52 Canadian - Project

[David Dunlop]

As I have been cleaning up the panels on the two 52-Set receivers, I became more and more curious regarding how much luminous paint had survived over the years and how much might have been replaced when the receivers went in for servicing. I have no idea of the history of the Main Set Receiver, but the Remote Receiver has an added, white decal below the Meter that states “NON-LUMINOUS DIAL” that I have assumed related to the Meter, as it is a different design than the ones on the other two receivers. So this receiver has definitely been in for some level of overhaul in its service life.

I did a little research recently to refresh my memory about Phosphorescent Paint, which confirmed the activating energy for the phosphors is ultraviolet radiation. And as luck would have it, our daughter’s Black Light was still tucked away in a corner of the basement. And it still worked!

Unlike Radioluminescent Paint that glows continuously until the phosphors burn out, the Phosphorescent Paint used on the 52-Set and 19-Set panels charges up during the day while exposed to natural ultraviolet energy and in the dark, the glow will last from 8 to 10 hours. Gradually fading away in the process. This cycle repeats itself daily.

I checked the Main Set Receiver, the Remote Receiver and out of curiosity, also my 1944 RCA Wireless Set No. 19 Mk III Cdn. I took three photos of each item. The first is in normal light. The second was taken while charging the Phosphorescent Paint with the Black Light for about two minutes . These second images show a combination of florescence off the various materials on the three front panels, as well as luminescence generated by the Phosphorescent Paints. The third photo in each set is a 12 second time exposure started immediately after the Black Light was turned off. It might be a bit hard to see in these smaller, low Resolution images, but the luminescence is actually quite bright initially but dims off quickly. In complete dark, the eye can see the glow for about 10 minutes. Actually not bad for 75 year old phosphors!

This first set of photos is the 52-Set Receiver. I will post the other two sets shortly.

David