Wireless Set No. 52 Canadian - Project

[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

[David Dunlop]

Part of my tool kit for the longest time was a small inspection mirror, about the size of those used by Dentists, but with a white nylon head, rather than metal. Had it close to 30 years before the nylon head started to perish and one day, while in use, it fell apart completely.

Found a replacement today at Canadian Tire. A little bit larger diameter mirror head but the handle is telescopic and the head has 360 degree swivel capability.

I picked one up to get a closer look at the three machine screws holding the upper BAND Switch and FREQUENCY ADJUST Switch plate in place. Its a very tight work space in that area of the receiver chassis, even with the upper front panel plate removed. I was delighted to discover the three machine screws are fastened directly into the top folded edge of the lower panel plate. No hex nuts and lock washers to deal with. Big thanks to the original designers of the 52-Set for that stroke of genius. That basically leaves a single soldered aerial connection to deal with, although I still need to remove the two aforementioned switch knobs to check for any shaft mounts fitted to the switch panel.

David

[David Dunlop]

Over the past few days, I have been able to remove the damaged BAND and FREQUENCY ADJUST Switch panel from my Main Set Receiver and replace it with the undamaged one from the backup receiver. In the process, I also took the time to examine all the Valve Shields and Caps in the two units and apply the best of the lot to the Main Set receiver.

All this was not done without incident, however. The issue in this situation turned out to be the Band Selector Switch knob on the backup receiver. It simply did not want to come off the switch shaft and there was nothing at all to leverage against, other than the panel behind it that I needed…undamaged. I tried everything I could think of for the better part of an hour and a half and could only gain half the distance needed to get the knob off the shaft.

This turned out to be a VERY interesting little switch. It is actually mounted on a sub chassis on the right hand side on the main chassis assembly. The knob shaft passes through a small support collar on the switch panel and straight back about 3 inches to a support sleeve about an inch and a half long. Immediately behind this rear support, the shaft ends in a brass gear, part of a two gear right angle drive that feeds the selector action to the actual switch on the right hand side.

After studying this arrangement for a while, I realized I could loosen the grub screws on the rear support sleeve and brass gear on the end of the knob shaft and slide the entire shaft straight out the front of the panel. I could then remove the offending knob and reinstall the knob shaft. Almost.

Things proceeded well until I arrived at the last item: the brass gear on the end of the shaft. Seems the last dear soul who worked on this particular item did not feel the grub screw had been secured safely until the Bristo Key had been turned a sufficient number of times to completely round out the inside of the grub screw. And then the daft twit probably continued to turn the key further, while consuming a large pot of coffee! Sigh!

I really hated having to resort to it, but out came the hack saw and off came the front 1.5 inches of shaft with the offending knob still attached. Even in this new free state, I had to lock a pair of vice grips onto the shaft stub and gently lever the knob with a hammer claw to finally pop it from the shaft undamaged. Interestingly enough, after careful cleaning and inspection, this knob slipped quite happily onto any other shaft available, but did not want to go back on the piece of the one it had just been pried from.

I was feeling pretty bummed about having to trash an otherwise good shaft assembly, but when talking to a friend last evening, he advised he has a box full of NOS switch shafts and can easily enough find one I can use to replace the one I had to cut. I will just have to drill out the damaged grub screw from the brass gear, carefully, install a new grub screw and it should be good to go.

One other small discovery was that when I removed the outer most 12SC7 valve from the Crystal Calibrator, I discovered the central alignment pin was missing and the inner glass envelop stub was cracked. So that valve was clearly not working anymore. I found the pin stub still sitting inside the valve socket, fished it out and installed a new 12SC7.

David

[David Dunlop]

I almost forgot to pass along a soldering tip in case anyone else needs to do soldering work on the 52-Set Receiver Aerial connector.

The soldering terminal in question is less of a typical terminal and more an extension of a small piece of heavy sheet steel. It sits on top of a much larger, vertical piece of sheet steel, same gauge as the main receiver chassis steel, to which the two aerial terminals are fitted, along with the right hand side Clip for the ARRESTERS, PROTECTING, GAS GAP. In fact, the accumulation of steel at this point is so thick, a 1/8-inch thick steel spacer is fitted between the left side ARRESTERS Clip and the back of the sub panel to bring both clips parallel to one another. The net result is the creation of a massive heat sink for the aerial connector, which needs to be taken into consideration for any soldering work.

My soldering station iron, set to its normal 350 degrees C, only generated enough heat to let the soldering tip skate about on the surface of the solder. I had to haul out the trusty vintage WELLER HD Soldering Gun to get the job done.

Also, I have no idea just how much heat the glass envelop of the Gas Gap Arrester is designed to handle, so I removed it from the clips prior to working on the terminal connection. Apart from the unknown heat risk, the right hand clip sits directly under the soldered aerial terminal and there was a good possibility any solder dripping from the terminal could wick into the space between the arrestor end cap and its clip.

As it was, it took about 5 minutes after completing the work before either aerial terminal or the right hand Arrester Clip were comfortable to touch.

David

[David Dunlop]

While looking up this item in the Master Parts List for the 52-Set today. I discovered that the Wing Nut used to secure it was not listed at all. Which was interesting because two versions of this Wing Nut (3 in total) are used in the 52-Set in two separate locations.

The first photo shows the NUT, ANF, Steel, Wing 10-32 version used to secure the titled PADS in the 52-Set Receiver.

The second photo shows the NUT, ANF, Brass, Wing 10-32 version used on the input terminals of the COIL, Aerial Tuning No.2A. There is an identical terminal on either lower side of the Coil Case, the output transmission connector from the Sender can be attached to, depending on the orientation of the Coil on the 52-Set Carriers No. 4.

I wanted to post this information in case anyone was looking for it.

David

[David Dunlop]

As I have been cleaning up the panels on the two 52-Set receivers, I became more and more curious regarding how much luminous paint had survived over the years and how much might have been replaced when the receivers went in for servicing. I have no idea of the history of the Main Set Receiver, but the Remote Receiver has an added, white decal below the Meter that states “NON-LUMINOUS DIAL” that I have assumed related to the Meter, as it is a different design than the ones on the other two receivers. So this receiver has definitely been in for some level of overhaul in its service life.

I did a little research recently to refresh my memory about Phosphorescent Paint, which confirmed the activating energy for the phosphors is ultraviolet radiation. And as luck would have it, our daughter’s Black Light was still tucked away in a corner of the basement. And it still worked!

Unlike Radioluminescent Paint that glows continuously until the phosphors burn out, the Phosphorescent Paint used on the 52-Set and 19-Set panels charges up during the day while exposed to natural ultraviolet energy and in the dark, the glow will last from 8 to 10 hours. Gradually fading away in the process. This cycle repeats itself daily.

I checked the Main Set Receiver, the Remote Receiver and out of curiosity, also my 1944 RCA Wireless Set No. 19 Mk III Cdn. I took three photos of each item. The first is in normal light. The second was taken while charging the Phosphorescent Paint with the Black Light for about two minutes . These second images show a combination of florescence off the various materials on the three front panels, as well as luminescence generated by the Phosphorescent Paints. The third photo in each set is a 12 second time exposure started immediately after the Black Light was turned off. It might be a bit hard to see in these smaller, low Resolution images, but the luminescence is actually quite bright initially but dims off quickly. In complete dark, the eye can see the glow for about 10 minutes. Actually not bad for 75 year old phosphors!

This first set of photos is the 52-Set Receiver. I will post the other two sets shortly.

David

[David Dunlop]

These three photos are of the Remote Receiver.

I was surprised to discover the decal referring to the presence of non-luminous paint was not related to the Meter, but to the fact the Frequency Dial was no longer luminous.

It was also interesting to see where the panel paint had been touched up, which is not readily apparent under normal lighting.

David

[David Dunlop]

This last set is of my WS No. 19 Mk III Cdn, all built in 1944, the same year as the Marconi 52-Set equipment. The Transceiver is RCA, the PSU is Northern Electric, the Crystal Calibrator is Marconi and the Pocket Watch is unmarked.

David

[David Dunlop]

A little bit more cleaning up work done on the Main Set Receiver this last week as I removed all valves with their related shields and caps and gave everything a good cleaning to get all surface dirt and oils off of them. Three or four valves showed a slight bit of looseness between the glass envelope and the base plug assembly, but nothing alarming. To be expected with 75 year old putty I suppose.

Prior to cleaning the valves, I had warmed the receiver up and used the Meter to test the valves it was intended to and found no response for V1B and V1F. After cleaning and reassembly, I rechecked the two valves on the Meter. The first couple of times on each valve, nothing. On the third time moving the selector switch to each questionable valve, the Meter Indicator twitched. Fiddling the switch a bit resulted in excellent readings for both valves. Turns out the problem was oxidation buildup on the switch contacts and not the valves. I have a can of contact cleaner kicking about somewhere, but have had it in the shop for quite a few years now. Might be best to purchase a new can and toss the old one when I find it. But in the meantime, another little problem solved.

The Handles No. 72 and Screws, Clamping No. C2 on the Frequency Dial of the Main Set Receiver are very badly chipped and oxidized. On my backup receiver, these items are mint, so I have decided the next project will be to swap them out. This means digging out my overhaul manual for the WS No. 19 and refreshing my memory on the correct procedure as it has been a while since I last did that work and it involves a number of fiddly bits and correct sequences as I recall. Interestingly, the Drives, Capacitor, No. C1 used on the 52-Set is identical to the one used on the 19-Set, but the 52-Set Parts List notes that the Drives manufactured for the 52-Set were built to higher tolerances than those for the 19-Set.

David

[David Dunlop]

I had a set of these that came with some 19-Set bits years ago. The Mic was finished in wrinkle No. 2 Brown. Recently I came across another headgear assembly, along with a couple of other items, for sale. This set apparently had a Mic that was finished in wrinkle Olive Green, and I thought that would make an interesting pairing for the 52-Set Project.

The three items arrived in the Mail yesterday and what had looked like the correct green in the photos, turned out to be another NATO Green repaint. On the bright side, however, lots of chips in the paint reveal that the original colour was also wrinkle No. 2 Brown, so it all works out.

David

[David Dunlop]

Two of these items were issued with the Remote Receiver Kit and were stored in the wooden Remote receiver Operating Case.

I had one Receivers, Headgear still in a parts bin, which I think had been left over from a number of Wireless Remote Control Sets I had accumulated years ago.

A few weeks back I came across another one of these headgear, still in it's original factory box. I am not certain, but think that when the 52-Sets were originally issued, all of the kit stored in the various cases would have been in original packaging and the Wireless Operators would have unpacked what was needed and the rest would have stayed unopened until needed. So I think this item will work well, whenever I find the wooden case for the Remote Receiver. One headset will be ready for action and the other still in the box.

David

[David Dunlop]

The last items that arrived this week were a pair of these replacement receivers, also in their original packaging.

A pair of these were issued as spares in the 52-Set Spare Parts and Valves Box and they would have served as replacements for either of the two headgear items issued with the 52-Set.

Interestingly, both this package and the earlier noted Receivers, Headgear, MC Cdn Mk 1, in its original packaging, were held at one time (May 58 actually) in 25 Central Ordnance Depot, Montreal, Quebec. I would love to have had a tour of THAT facility in the late 1950's!

David

[David Dunlop]

I am pleased with the results of the British Valve Adapter project I have been working on recently. I am 100% certain the adapter itself will work as intended. Before putting it to the task of checking the valves in my 52-Set receivers, however, I realized that after many years of very casual use, it would be prudent to calibrate my Precision 612 Tube Tester to ensure it is in good working order. This is actually a fairly straight forward task, there being only one tube in the tester circuit (a 5Y3GT), one capacitor and about 10 easily accessible resisters to be checked.

‘Pop the tube out. Give it a quick test, and pop it back in or replace it.’ My Brain said, far too eagerly. It took a while for the concept of owning only one tube tester to take hold. So until I can team up with a mate with a tester on hand, I have headed back to the 52-Set work on my bench.

The slow strip down of the backup receiver is continuing as per the first photo. The tuning knob bits are all together waiting to be used to upgrade the Main Set Receiver.

I had commented a while back the tuning on the Main Set Receiver was alarmingly stiff. I suspect the shaft supports, front and/or rear, of the tuning condenser shaft itself are at fault. I am hoping the issue is with the front end as it is quite easy to access. The other two photos here show the tuning shaft exiting the rear of the Flick Assembly behind the front panel of the receiver and heading into the coil spring like flexible coupling. The last photo shows the tuning condenser shaft exiting the flexible coupling and disappearing into the front shaft support of the Tuning Condenser Assembly.

David

[David Dunlop]

With the successful completion of my British Valve Adapter Project, I have now switched my attention back to working on the 52-Set Receivers.

I have managed t do a little more strip down of the backup receiver, freeing up the knobs, handles and a number of brackets. I am making a concerted effort to properly tag each of the parts with their ID’s and ZA/CAN Numbers and bag them for storage for future use. Something I have not been prone to do in the past.

As you can see, the poor old girl is looking a lot more forlorn now than she did a few months ago.

One thing I thought would be worth mentioning here, as a perfect example of it can be seen to the left of the Power Indicator Lamp, where one of the round chassis handles was located. A large section of the panel paint has fallen away in pieces. It is not always possible to prevent this from happening with 75 year old paint, but some care can go a long way to help minimize this potential problem.

During the original assembly process, fittings and hardware were being installed on new paint, which, depending on delivery timings, could be anywhere from a few hours to a few days old. In many cases not fully cured and hardened. Consequently, it is not unusual for the added fittings and hardware to bond to the new paint after they are mounted and the hardware run home and the paint continues its curing process. 75 years later, and you need to remove said piece, there is a good chance the piece you are removing will stick to the panel paint and pull a piece off when removed.

The other problem is the likelihood of oxidation developing on the surface of the metal, underneath the paint, over time. Even though the oxidation layer may be very thin, it has no strength, that means the bond between the metal panel and the finish paint coat has been compromised, even though the paint may look minty new.

When removing hardware or parts from a painted panel, it is a good idea never to turn the fitting, or hardware on the panel face. Use a screwdriver , or socket to hold the part stationary and undo/unscrew the hardware on the backside of the panel. This will help minimize the risk of scales of paint coming off the panel.


David

[David Dunlop]

You may have noticed in the previous post the voltmeter is no longer present on the backup receiver. It is now destined to replace the meter on the Main Set Receiver, as that one has a cracked Lucite face and happens to be the same make as the one on the backup receiver. Once I have removed the damaged voltmeter from the Main Set Receiver, I will send it off to have the Lucite face replaced and that meter will become the ‘Spare’ for the 52-Set.

Quite a few markings turned up on the back of this voltmeter, including the manufacturer’s ID cast into the center circle, between the two terminals.

DE J
USA

If anyone recognizes this company logo, please let me know who it is. As you will see in the last photo, the ‘E’ is half the font size of the other two letters and there is a space between the “E” and the “J”, which leads me to believe the company name might be French.

Interestingly, the three mounting screws for this meter went into independent hex nuts at the back of the panel. Not reinforced tapped panel holes. This will make it interesting when it comes to installing the meter in the Main Set Receiver, as there is precious little working room back there when the meter is in place.

I thought I would document the various markings on the back of this meter. There is another manufacturer of meters for the 52-Set out there and it will be interesting to compare the two eventually.

At the top circumference, is a small yellow stamp “ASA”.

At the top most back of the meter is a large white rectangular stamp with the following centered in it:

CALIBRATED FOR
STEEL PANEL

Just below this is a round white ring with

D
INSP

Centered in it.

Below the terminals is a two part white number “150 24”. Perhaps the manufacturers stock number. It is one number too short for a CMC part number.

The last stamp is a large yellow bordered square below the left side terminal. This has “TESTED OK” stamped inside it.

The other marking shows up in the last photo, just above the left side (Positive) terminal. It is a handwritten mark, scratched into the bakelite that reads:

25/4/58
Fine

A possible inspection date.

I also noticed that the positive terminal is missing one brass washer. Each terminal should have two, the small ring connectors on the two meter leads fitting between the two brass washers. Fortunately, a local hardware store stocks older brass hardware so this piece can be easily replaced.

David

[Bob Carriere]

Hi David

Do you have a closeup of the face....? Are they not used on other similar radio/receivers...? like the 19 sets.....? diameter of case in inches
Bob C

[David Dunlop]

Hello Bob.

I hope the snow is melting in an orderly fashion out your way these days.

Here are a couple of photos comparing the 19-Set Voltmeter on the left with the 52-Set Voltmeter on the right. Both are designed to mount in a 2-3/16 inch panel hole with 12, 4 and 8 o’clock mounting hardware positions, but the similarity pretty much ends there.

That panel hole arrangement was quite possibly standard on many wireless sets, but the meters for the most part would be custom designed to work with the circuits unique to each set.

It would also seem that wireless meters evolved quite a bit from simple indicators to quite useful diagnostic tools for the operator. These dual scale meters not only allow the operator to monitor input voltage to the supply on the smaller scale ( 6, 12 or 24 volts), the Low Tension side of things, but also the power supply output voltage on the larger scale, the High Tension part of the set.

The Low Tension would typically be the battery input voltage, which was also the filament voltage for the tubes. A drop in Low Tension voltage would warn the operator it was time to switch to the second set of wireless batteries and recharge the first set. Normal Low Tension readings with no output from the wireless would indicate a possible failure in one or more valves.

The meter on the 19-Set could also tell you when the set was properly tuned to the available aerial you were using and the relative strength of your out going signal.

The 52-Set meter could do all of that plus had a feature on the receiver meter switch that allowed the operator to test each individual valve in the receiver to see if it was in good working order. The Operator could also turn this switch to a ‘SENDER’ position and then use a similar switch on the Sender (Transmitter) to test the valves in that unit as well.

All that while brewing up his morning tea!


David

[Bob Carriere]

Never realized that the 52 set had such diagnostics features .....amazing how progress was made from one radio model to another.

Bob C.

[Mike K]

Meter info .

http://www.schoolphysics.co.uk/age16...oil/index.html

https://en.m.wikipedia.org/wiki/Galvanometer

[David Dunlop]

Well I found out late last evening that the meter I was curious about was manufactured by the DeJur Company. It was apparently founded by two brothers in the 1920's in Connecticut and eventually relocated to New York State. They seem to have developed quite a good reputation in the radio sector for their tuning capacitor design work and their electrical meters , which were highly regarded.

At some point the company became DeJur-Amsco and they are now very well known in the Photographic Industry for their Light Meters.

David

[David Dunlop]

Interesting articles, Mike. Thanks for posting.

David

[David Dunlop]

An interesting bit of 52-Set information made a surprise arrival this week.

I had asked a friend in Edmonton to document the data plates on his 52-Set for me whenever he had a chance, so I could pass the information on to Jacques Fortin, in Quebec, who is assembling a database of known surviving 52-Set components. The set in question was on a pallet on a high shelf in his shop with an array of M20 parts in front of it.

A forklift finally brought the 52-Set down to earth and photos of the data plates were received and sent on to Jacques.

The big surprise was the data plate on the Main Set Receiver, photo attached.

Not only is it unlike any other 52-Set data plate I have ever seen, the serial number is unlike any other 52-Set serial number I have run across. The composition of the plate is thin Bakelite, with the white lettering painted on the Bakelite. It is completely devoid of any references to Canadian Marconi and it’s part-numbering system, and it is not the normal four-digit number between 5000 and 9000 that one would expect.

My first thought was the plate was a fake, so I asked my friend to pull the receiver out of its Carrier No. 4 and check to see if a Mod Card was located in it, to see what it had to tell us. Indeed there was. Notice the second photo. The modifications to this set were not done until 1964. The modifications performed have been in existence since November 1945, when Modification 1 came into being: The Installation of the Modification Card Holder inside the component.

So my thoughts are that this 52-Set Receiver was build around the same time as all the other 52-Set pieces known so far, 1944, boxed up and stored somewhere in the Army Supply System, until it was put into service in 1964. When requisitioned in 1964, it was unpacked and the modifications needed were performed and the receiver delivered to whatever unit needed it. With this data plate in place from the start.

The other pieces of information my friend has about the history of the set are that he purchased it directly from the Crown Assets facilities in Edmonton when it was surplussed out and that the paperwork he got from Crown Assets confirm all the components he has were the complete set Crown Assets sold as a single unit.

Bakelite seems a very fragile medium to make a data plate out of, especially when it is thin. And the serial number looks very odd. It is almost like it identified this receiver as the 25th out of an unknown number built for an Order or Contract Number 4075.

I now wonder how many other 52-Set components are out there with similar Bakelite data plates. I cannot recall thin Bakelite ever being used for data plate material on anything before now. and why such a vague and fragile plate?

David

[David Dunlop]

I had to pass on one of these last year, as it simply wasn’t in the budget at the time it showed up for sale, However, a few weeks ago, a gentleman in Kent, England had a post on the internet with a number of NOS ones for sale.

My Daughter and three Granddaughters had given Papa some Mad Money to put towards my WS No. 52 Project for Xmas, so I was quite pleased to be able to order two Holders to replace the ones removed from the Remote Receiver and Main Set Receiver when still in service.

It’s always fun to find old stock with original packaging and these two holders were no exception. Each still has its factory tag attached with a small run of hemp cord. The tags read:

ZA/4250 HOLDERS, Watch, Multi-purpose Part, Qty 6


David

[David Dunlop]

This is undoubtedly going to be a long project and I am carefully avoiding any thought at all about an anticipated completion date for it. The bright side of this, however, is the lack of stress about ‘finishing on time’. It will be done when it’s done.

The other nice thing about this approach is that it allows one to focus on and enjoy the little milestones as one reaches them. They don’t get brushed aside because of looking so far down the road at ‘meeting the deadline’.

I reached one of those little milestones this morning when I was able to reinstall the two Holders, Watch on the fronts of the Receiver and Remote Receiver. These were removed back in the early 1960’s, when the receivers were still in service and the three empty holes at the top of each panel were a constant reminder of the missing parts, and they were the only missing parts on both receivers.

There are still a few rusty/worn hardware items I want to swap out for better condition ones on the main set receiver and a few other physical things to attend to, but it is finally getting close to the same condition physically as the remote Receiver.


David

[Bruce MacMillan]

David, very nice work. I hope that you will have it operational for QSO's on the 75th anniversary of D-day .

Your dedication to restoration is to be commended.