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Old 07-02-18, 19:43
David Dunlop David Dunlop is offline
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Join Date: Feb 2006
Location: Winnipeg, MB
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With a bit of free time to play with this morning, I decided to dive into the AC Cord repair on the ZE-11 Remote Supply.

I assumed there would be two main parts to this work: a physical part dealing with the placement of the cord, and, an electrical part dealing with the usual desoldering and soldering of the two cord connections wherever they happened to be.

The first step was to remove the base plate from the supply. Straight forward enough. 12 small round head, slotted screws with lock washers, three per side. 11 screws were found to have the split lock washer style, the last one an internal tooth lock washer. Easy enough to eventually upgrade the latter to the correct style. Nice surprise inside the base plate. A very minty, lacquered circuit diagram for the supply.

After admiring the diagram for a few moments, I had my first reality check. Things can get quite crowded inside this equipment! It took a moment or two to confirm where the ac cord entered under the chassis. I had hoped the anti-strain devise used on this cord would be a simple knot tied into it to limit movement of the cord back out from under the chassis. Nope! This little puppy was held firm with a small ¼ inch clamp. Roughly dead center in the photo, you can see the small hex nut securing the clamp. Just to the right of the C22A Capacitor next to the ‘22’. Once you spot the nut, the clamp curve is quite evident with the two sections of heavy ac cord looping out. One lead ran straight to a pin terminal on the AC Selector Socket. The second shorter lead went up to a terminal on the 115V/230V Selector Switch.

Fine so far.

Step 1: Lets free up the AC Cord so the 4 inch damaged section outside is now inside where it can be removed and enough new, solid cord used to reconnect everything. The crowded conditions are really starting to make an impression on me now. The hex nut and visible screw securing the clamp are tucked under the C22A Cap just enough that I know removing the nut with a ¼ inch socket should be OK, but getting the nut and supporting lock washer back in place from underneath the chassis will be the tricky bit. Best check how accessible the screw is from top side. Of course. No visible screw topside!

A few careful measurements later, I discovered the screw used to secure the AC Cord Clamp is actually one of the screw posts fitted to the Transformer Cover on top of the chassis. That pleased me in so far as having figured out the transformer, choke and their respective covers must have been added to the chassis at, or just before, the AC Cord was fitted. But that did not cheer me up too much when I realized just how much more wiggle room the assembly line worker at Marconi must have had, compared to myself, when working on this part of the assembly.

In any event, out came the appropriate sized ¼ inch socket and off came the hex nut. Some careful use of a set of needle nose pliers, and out came the nut and the lock washer, followed by the clamp.

David
Attached Thumbnails
WS-52 ZE 11 Remote Supply F.JPG   WS-52 ZE 11 Remote Supply G.JPG  

Last edited by David Dunlop; 08-02-18 at 01:38.
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