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Old 05-12-21, 19:16
David Dunlop David Dunlop is offline
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Join Date: Feb 2006
Location: Winnipeg, MB
Posts: 3,384
Default SUPPLY Unit ZA/CAN 4772

And off we go, into the unknown yet again!

I have now pulled the Supply Unit from the Carriers No. 4 and it is sitting on the bench ready for a close inspection. This Supply Unit is getting interesting already.

Overall, the interior chassis assembly is remarkably pristine. Only the top surface has accumulated any significant dirt and/or surface rust and that should all clean up fairly easily. This condition looked odd, in light of the fact the Serial Number for this Supply Unit is 5792. That is early production. The other interesting bit is the Blower Cover and Receiver Vibrator Supply Cover on the front still clearly show the factory original Gloss Navy Grey paint, The discoloured varnish top coat is only on the main Supply Unit Panel that had new decals applied during the 1966 Workshop overhaul. The only reason I can think of for the replacement of the decals is that somebody assumed they were radioactive paint. That would fit nicely with the fact the Sender panel had two decals added to it stating the paint WAS radioactive. It is not. All the more reason to be happy the decals will eventually be replaced with ones patterned after the originals down the road.


The Modification Card, still in place in its holder, has proved a gold mine of useful information, which may explain a lot of the history of this, 52-Set. Modifications 1, 2 and 4 were all performed on this Supply Unit 12 June 1966, which is consistent with the 1966 Workshop Decals added to the upper left corner of the front panel. Modifications 1 and 4 are the interesting ones.

Modification 1 was for the installation of the Modification Card Holder. This Instruction was first issued 23 May 1947, when these Card Holders were first introduced and to be applied to all active wireless equipment assemblies. That strongly suggests this Supply was sitting in original packaging from whatever build date it had until it arrived at 202 Workshop, possibly as a replacement unit for the one originally in this particular 52-Set. At 202 Workshop it was unpacked for the very first time, the two Dynamotors upgraded to the improved 1945 versions, the ‘bad decals’ replaced on the front panel and the Modification Card Holder added on the top of the chassis.

Modification 2 was a simple addition of electrical tape around the right hand terminal of resister R38A at the back of the supply to prevent possible contact with the Vibrator Supply Case when it was slid into the Supply Unit Chassis.

Modification 4 gets really interesting again. This was an extensive set of modifications required to prepare the Supply Unit for operation in conditions in the high arctic. Mostly upgrades to grease and other lubricants, but a couple of valves were also swapped out for more cold tolerant ones.

So where did this 52-Set originally come from for servicing at 202 Workshop, or, where was it going to go after completion of the overhaul work, which would have been leading towards the winter of 1966-1967?


David
Attached Thumbnails
WS No. 52 Supply Unit 7.JPG   WS No. 52 Supply Unit 8.JPG  
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