CPP - 5 Power Supply

[David Dunlop]

Poking about in my Canadian C42 Set Manual again this morning and noticed for the first time that there are two possible Power Supply, Metallic units which can be used with the C42. One is the familiar CPP-2 Supply but the other (new one to me) is a CPP-5. No information at all to make comparisons between the two, but the Stock Number given for the CPP-5 is: 6130-21-106-5071

Anyone shed some light on this Supply?

David

[rob love]

6130-21-100-1287
DMC: F
STATUS: Item is "Cancelled without Replacement"
Date CGCS Established: 03-JUN-1968
STATUS Date: 28-APR-1998
Last Updated: 03-JUN-1968
ITEM NAME: POWER SUPPLY
Narrative DescriptionMETALLIC,FULL WAVE,INPUT VOLTAGE,90/130 VOLTS AC160 HZ 1 SINGLE PH,OUTPUT VOLTAGE,NO.,1.12 VOLT,22 AMPS,N O.,2.24 VOLT11 AMPS,SPEC CPP-5

USERS:
RNCCRNVCReference NumberNCAGE691001287
3591532CPP5
80058

(Same outputs as the CPP2)

[BCA]

You'll know a CPP-5 when you try to lift it. Although it looks like a CPP-2, and is only 2" deeper, it weighs 129lb compared to the common CPP-2 at 95lb. The main difference is that the CPP-5 was meant to be used with 25 cycle per second power (the standard before our general conversion to 60cps) while the CPP-2 is used for 60cps power. Old electrical appliances like clocks sometimes have the sticker that indicates they were converted from 25 cps to use on newly introduced 60 cps. ........ Brian

[David Dunlop]

Ouch! I wouldn't want to find one of those on the bottom shelf of the local surplus store. I thought my AR88 Receiver was heavy at 100 lbs and 3/4's the volume of the CPP-2!

[BCA]

I believe that the lower 25 hertz frequency required heavier transformers that for use with 60 hertz power. 400 hertz aircraft devices may have gone to a higher frequency to cut down weight. Can anyone clarify this? Also I suspect that a heavier 25 hertz device might work OK at a higher frequency, say 60 hertz. But not possible to go in the other direction.... Brian

[Bruce MacMillan]

Originally Posted by BCA

I believe that the lower 25 hertz frequency required heavier transformers that for use with 60 hertz power. 400 hertz aircraft devices may have gone to a higher frequency to cut down weight. Can anyone clarify this? Also I suspect that a heavier 25 hertz device might work OK at a higher frequency, say 60 hertz. But not possible to go in the other direction.... Brian

Right on the money Brian. The older power generators around Niagara and other areas of the the northeast were 25 cycle. Because of that they needed a bit more iron. A 25 cycle transformer will work on 60 cycle except for synchronous motors like clocks. It doesn't work the other way around.

Aircraft went to 400 Hz to reduce weight. Modern supplies can work into the MHz range.

It's the weight of this equipment that coined the term "boatanchor" when referring to old radio equipment. Prior to moving I had to sadly give up a couple of Canadian Marconi CM11 sets weighing about 350 lbs each. The kicker was a pre war RCA RAB USN receiver. It weighed 460 lbs.