Wireless Set No. 52 Canadian - Project

[David Dunlop]

This is the largest of the three wooden Boxes/Cases of equipment issued with the 52-Set Canadian. These photos are of one of these boxes courtesy of Chris Bisaillion.

The inside is divided into three sections. The centre section holds the Remote Supply Unit for the Remote Receiver. It is a heavy little sucker and this central location in the wooden case places it directly under the carry handle on the lid of the case, thereby keeping things nice and balanced for the lucky Private who has to lug it about.

The left section stores the two headsets and the cables and remote aerial needed to operate the Remote Receiver. The right side section held the spare valves and other delicates for the receiver. You can see on the lid above this section, a square of KimPac padding to protect the valves. The rest of this section of the case was likewise padded.

Originally, a square paper label would have been glued to the inside of the lid, listing all the contents of the case. This has been replaced, as of July, 1962 by an envelope with a new List of Contents utilizing the newly introduced NATO Stock Numbers. Hence the large wash of tan paint across the front of the case covering the original wartime stencilled ID and the new NATO Stock Number Data applied there.

It is possible that 1962 saw the end of the WS. No. 52 Tool Box as a separate entity in the Canadian Army supply system.

David

[David Dunlop]

While looking through the 52-Set Manual again this afternoon, in particular at the spare parts listed in it, it struck me the headset gear used with this wireless is fully compatible with the 19-Set equipment and that got me taking a deeper dive into my 19-Set spare bits boxes. And there they were.

2 spare Microphone Capsules, PC 90617C (ZA/C 00082) used in the standard microphones. Both are in good working order. One shows the remains of a red patch on the back centre with what I think is the Philco stamp. The other only shows a faint circular inspection stamp with a two digit number in the middle.

More digging, and up surfaced a Capsule, Microphone NEPP 59450, RCA 118-262-1 (ZA/C 00085). It has an orange date stamp on the back of it ‘5/44’, and near the front centre is stamped ‘W.E.Co’, which I am guessing means this capsule was made by Western Electric Company. This is the spare capsule for the Microphone, Hand, No. C3.


David

[David Dunlop]

I have lost track of the number of times I have looked at my three 52-Set receivers in the last year, but while studying the two Main Set Receivers last evening to consider the best options for a challenging physical repair down the road, I discovered something new. There are two different voltmeters present among these three receivers. This should be no surprise considering the number of meter makers for the Wireless Set No. 19 during it’s production history, but the 52-Set had a much shorter production run, with only the Canadian Marconi Company as the sole manufacturer.

It didn’t help that in this particular instance, the odd meter out happened to be on the Remote Receiver, with the other two being on Main Set Receivers. I am content at the moment to consider that a pure fluke.

Checking the 52-Set documents I have on hand, all photos and drawings match the voltmeters on my two Main Set Receivers (the first photograph attached) having the flat bottom to the face plate that exposes a lot of the internals to easy view. The voltmeter with the crescent shaped glass is on the Remote Receiver and has the faceplate with the two large lobes either side of the pointer.

The 1945 Master Parts List describes only one voltmeter, as follows:


VOLTMETERS, DC 2-in Double Scale 0-15/300, No.C1

“Bakelite Case 1.27/64 – in x 2.11/16 – in dia; 3 1/8 – in mounting holes; fluorescent pointer; shatter-proof glass; two terminals on back of case; external resistors must be used, this is a miliameter. ZA/CAN 4304



David

[David Dunlop]

I mentioned I have been taking a closer look at the restoration of my main set Receiver now and am having some second thoughts regarding my original approach to this phase of the project.

Of the two main set Receivers I have to work with, I was initially targeting SN 8349, a late production unit, for restoration. Visually, it is a very clean looking set, which meant no paint restoration work would be required. On the dark side, however, it is missing the complete Slow Motion Drive assembly from the tuner, has one broken connection to be resoldered, but most challenging, the centre terminal wafer on the Mode Switch S2A is totally shattered beyond repair and would have to be replaced. That is where I thought my backup Receiver SN 6691 would come in handy. Once I had used it as a working reference during the restoration of the Remote Receiver, it could become the doner for the necessary parts to restore the aforementioned SN 8349. The more I study the shattered S2A wafer terminal problem, the less enthused I have become about attempting that repair.

Apart from the complete physical disassembly of the two S2A switches, I also have to deal with soldering and unsoldering seven connections, twice, in a very cramped location. And if anything happens to that replacement terminal wafer in the process, I am pooched! So a closer look at Receiver SN 6691 was needed.

On the positive side, it is quite happy having electrons flowing through it. In that regard it provided very helpful information when trouble shooting the Remote Receiver. Three of its valves gave a very low meter response when checked in the set, but that is an easy fix. Yes, it has a lot of dust, cobwebs, nicotine accumulation and some surface rust on some sections of the horizontal bottom chassis, but I am guessing two thirds of that should clean up just fine. This Receiver has definitely had a working life. Also appealing to me is the fact it has the second version of tuning decals on it: the solid black rectangles with the Red and Blue coloured ‘A’ and ‘B’. The Remote Receiver has the last version of tuning decals: the solid black rectangle with white ‘A’ and ‘B’. So keeping this Receiver helps save another small piece of production history for the 52-Set.

The biggest negative regarding Receiver SN 6691 is that the paint and decals surrounding the BAND Switch and FREQUENCY ADJUST Switch are nearly gone from the BAND Switch and could fall off at any time around the latter switch. This is a result of humidity over time oxidizing the plating on the chassis metal underneath the paint in these two areas. The paint loses its bond with the chassis and breaks away very easily. Taking a look at these two chassis plates recently, I have discovered they are mounted to the top of the lower face plate assembly with three screws and only one soldered connection to the upper Aerial Terminal. So it looks like I can swap the good plate out from Receiver SN 8349 and put it on Receiver 6691 very easily, with only a single soldering connection to deal with on each receiver. I can then part out Receiver SN 8349 as needed to keep the project going.

I have attached a couple of comparison photos of the two switch plates in question, along with a vertical shot down the back of the plate on Receiver SN 6691 to show the three mounting screws and aerial connection. The surface rust on the bottom chassis looks worse in the photo than it actually does in real life.


David

[Mike K]

Just wondering how you tested those old 19 set moving coil mic inserts . I used to use a oscilloscope and place the probes on the insert and.speak and observe the output voltage. Dont know if that's a correct method but I could see the dud inserts because they had a lower voltage reading. Here in Aust. new 19 set harness sets were made in 1956 ( as replacements for worn out WW2 stock ).Nylex brand . I bought many of these Nos in the box for $2 each .

[David Dunlop]

Hello Mike.

Quite a Primitive approach, actually. I use my old 19-Set with two working sets of headgear, in IC Mode. If nothing happens the first time, I take the element out, whack the back of it on the table top a couple of times and try again. If it still does not work, I go on to the next one. I have not run across too many dead ones. Even rather scruffy ones can produce good results and its an item where looks are not too critical because they end up hidden when working. Pretty ones that work do look better in the Spares Box, though.

I do like your approach and must try it out. A lot less dramatic than mine, and with just the right touch of Alexander Graham Bell about it.

David

[Mike K]

Ok whatever is effective ! I have few NOS inserts somewhere for the 62 set harness with the smaller round handset without a handle. The wartime Aust. Made inserts for the 22 set (Aust) were often troublesome , the sets suffered with low modulation levels