Power Supply, Metallic, CPP-2

[David Dunlop]

I was able to replace the power cord on my new arrival CPP-2 today, and while I was at it, copied down the two serial numbers form my supplies. Both of these CPP-2's are later versions that incorporated a hatch on the front left side of the cover to facilitate changing the knife switch inside from 12 to 24 volts output mode. Earlier models of the CPP-2 lacked this feature which meant the entire top cover had to unscrewed and removed (7 screws) and then replaced, each time a changeover was needed.

These supplies were manufactured by STANDARD RADIO PRODUCTS, a Kitchener, Ontario based company, the status of which today, I do not know. I think some of their products may have had data plates on them bearing just the word 'STANDARD', but I have no guarantees on that.

The two serial numbers I have for the CPP-2's are:

1319
1504

Both were built in 1952.

That last point has not registered with me until now. I first became aware of these Power Supplies through the series of Canadian Army Manuals for the C 42 Set, printed roughly between 1958 and 1962. I now suddenly realize these CPP-2's were in the Canadian Army Supply System nearly 10 years before the C42 Set. So that raises the question as to what prompted them to come into being?

AC Power Supplies for the 19-Set came on stream in the late 1940's to remove the problems of wireless batteries being used for indoor operation of the 19-Set. Was it then, perhaps realized, other wartime wireless sets still in common use indoors would also benefit from such a conversion to AC operation, but a more generic approach to the problem was needed?

It might be interesting to see just how big a production run of CPP-2's actually happened.

David