Wireless Set No. 52 Canadian - Project

[David Dunlop]

As per the attached illustration from the 52-Set Master Parts List, the Crystal Calibrator in the receiver is serviced as a complete unit. In reality, it is made up of three sub-components, from back to front: the calibrator chassis, the extension assembly that gets the calibrator panel far enough forward to line up with the upper front panel of the receiver, and the calibrator panel assembly itself that includes the switch and indicator lamp.

When installed in its location in the upper left corner of the rear chassis wall of the receiver, there is only a ¾-inch clearance between the side of the calibrator assembly and the left side wall of the receiver chassis and the front of this receiver side wall bends inward ¾-inch to support the upper front panel of the receiver when it is in place. Two slotted round head screws and external lock washer sets secure either end of the calibrator to the rear chassis wall of the receiver.

I suspect that the assembly line station where the crystal calibrator was installed into the receiver chassis was equipped with an overhead, flex cable driver rig similar to a dental drill. It probably had an angle head with interchangeable bits and would have worked easily to mount the calibrator quickly. Once mounted, three leads on the right side of the calibrator chassis would have been soldered in place: HT, 12 Volt and OUTPUT, and the e installation would be done.

However, to remove the crystal calibrator from the receiver, one first has to remove a pair of slotted, round head screws and external lock washers on the bottom side of the union between the calibrator chassis and the extension assembly, and a pair of slotted, pan head screws only at the top union. The loose section of the calibrator can then be swung to the right side enough to get a ¼-drive socket and extension in place with a slotted driver head to undo the four screws mounting the calibrator chassis to the receiver.

Best to unsolder the three leads to the calibrator first, however,

The innards of this calibrator are quite similar to the one designed for the Wire Set No. 19.


David

[David Dunlop]

When my first 52-Set Receiver arrived and I had a look at the inside of it, I had noticed a four digit number scratched into the metal on the left side chassis wall about midway up the back end of it. In addition, the same number appeared in large black grease pencil, or paint. My initial thought was it might have been the serial number of the receiver added to the chassis during production, but the number did not match the data plate. Same thing was noticed when the other two receivers eventually arrived. So I filed the information away and forgot about it essentially.

When I removed the Crystal Calibrator from my Parts Receiver the other day, I was quite surprised to find another four digit number written in grease pencil, or black paint, on the inside chassis wall of it as well. As per the attached photos, this calibrator number is ‘6641’. The number inside the Parts Receiver is ‘6215’. Not identical, but interestingly close.

I am thinking now, that these numbers are perhaps Production/Assembly Control Numbers used on the various lines for data gathering and quality control. If these numbers were logged in and out at each work station on the line, at the end of each shift, it would be easy to determine the number of assemblies processed each day, for example. Or if defects showed up, it would be relatively easy to isolate the range of assembles that would need to be inspected and/or corrected.

I will have to check for these numbers in the Sender and Supply Unit and Remote Supply as well now.

David