Wireless Set No. 52 Canadian - Project

[David Dunlop]

With the holes drilled in the copper bar now, I could do the assembly of the hardware to the bar.

The centre post will be the connection point for the actual cable to ground. I could not find a round head, slotted, brass screw in the length I wanted but ¼-inch countersunk, slotted were available along with matched brass finishing washers, so I went that route.

The two outer posts will be the pair of terminals on the front of the electrical box, upon final assembly. The sets of three brass hex nuts on these posts, directly behind the copper bar, are merely serving as spacers to allow sufficient clearance for the center post, behind the front cover. Without them, the copper bar would simply bend over the centre post when the hardware for the two terminal posts was run home.

Next step for this assembly will be to give the electrical box a coat of flat white paint and cure.

David

[David Dunlop]

I was able to get a little more work done on this part of the project as well this morning.

After studying the hole in the back wall of the box, where the original hardware was installed, I found it was 11/64-inch in diameter. Just the right fit for a 10-24 screw. The outer hole in the box, partially tucked under the right lower hinge plate, was countersunk. The edge of the hinge plate was bowed outward slightly from the original screw being hammered back out of the hole when removed, but I think I can fix that easily enough down the road.

Test fitting the new bracket and taking s few measurements gave me a probable length of the original screw as being 1-inch. So far so good!

The hole in the bracket for the screw is centred in one end of the bracket. Once again, to give myself a little wiggle room getting the new bracket correctly lined up inside the box, when I install it, I went with a 13/64-inch hole in the bracket.

The new look of the metal on this replica bracket did not match well at all, when test fit directly across from the smaller surviving bracket, so I decided to age it with some zinc plating. This time, however, I did not go through any of the recommended cleaning steps to be done before plating that would normally give one a good even distribution of new zinc on the bracket. I just hooked it up, along with its hardware, and dropped it in the solution for one hour.

Sure enough, the final plating was very patchy and random, and much more like the surviving original. I am quite pleased with it, but have now discovered yet another step may be required. To confirm this possibility, I will need to take another close look inside the box, out in the sunlight. It is going to be raining here again for the next four days!


David

[David Dunlop]

It was not supposed to, but the sun actually broke out after lunch yesterday and stayed out until mid evening, so I got a little more project work done than I had initially expected.

First off was to get the toolbox out onto the patio for a closer look at its assembly history. The rectangular patch of bare pine wood, where the missing bracket had been mounted was always quite visible, but what I now noticed was the spray paint shadow of thin paint angling down to the bottom left side of the rear wall, about 10 degrees. That told me a lot. The countersunk hole for this bracket hardware was drilled early on in the assembly process. The bracket then had to be installed and the countersunk hole filled in before the hinges were installed, as the right side hinge strap covers part of this countersunk hole.

I then cleaned off the smaller front bracket that holds the tip of the soldering iron and was very surprised to see close to 90% of the original Flat Olive Drab paint was still in place on the two inner surfaces of the bracket. There was little at all left on the back/outer face that would have been exposed to the comings and goings of various tools over the years.

A look at the underside of this bracket with a mirror showed nothing but surface rust and original plated metal covered with a thin skin of oily dirt.

I am glad I took the time to age the metal on the new bracket, but the original plan to leave it all bare metal is now out the window. This bracket supports one end of the small wooden box the Hydrometer is store in. I would be surprised if the hydrometer box and contents weighed much, if anything, over 1 pound and there is very little room for it to move around in this bracket. My thought, therefore, is that if the original bracket had still been there as well, it would also have a very high percentage of surviving original paint on its two inner surfaces and most, if not all, of the paint on the outer end facing to the interior of the tool box would have ben worn away, just like the surviving, smaller bracket.

So I have some painting yet to work out before installing the hydrometer bracket.

David

[David Dunlop]

Along with getting a better look at the interior of the tool box yesterday afternoon, I was also able to paint the electrical box destined to become home for my wireless set ground terminals.

This morning, after the cover had cured to the touch enough, I hauled out my trusty vintage Letraset and labeled the cover plate. I like to do this at this point in time because as the paint continues to hard cure over the next few days, it forms a strong bold with the applied lettering This saves me having to apply a clear coat.

I was also able to mount the grounding terminals assembly to the front cover. So far so good.


David

[David Dunlop]

It took just over two years to finish this Ground Terminal, but I did so this morning.

Sorry to have bored your gizzards out with this little sub-project, but it will, eventually, tie in with the restoration of the 52-Set and help keep all the electrons happy when the time comes to put them all to work.


David

[David Dunlop]

I now have the replacement bracket clamped to the side of a piece of 2 x 4, and I have the mid-section oriented perfectly flat.

The plan is to use this setup for the creative painting ahead to try and blend this new bracket into the original interior of the toolbox.


David

[David Dunlop]

With finally getting caught up on most of the yard work today, I was able to put some time in this evening to give the new tool box bracket an initial coat of Flat Olive Drab paint to start the process of hopefully blending it in to the rest of the tool box.

A bit hard to tell where this is all headed at the moment, with the paint still largely wet. I should have a much better idea tomorrow after its dry.


David

[David Dunlop]

As it turned out, there were just two small adjustments I felt were needed with the paint work on the replacement bracket, to make it look at home in the tool box,

I added paint to the left edge of the bracket as this paint had largely survived on the left edge of the surviving front bracket.

I also added some horizontal and vertical scuffs to the upper face of the bracket where tools moving passed it over the years would have worn away a lot of the paint. This also brought it more in line with the front bracket.

The enlarged hole I had drilled in the bracket did indeed come in handy when installing the bracket. It allowed enough wiggle room to get the bracket properly aligned with the original paint shadow on the back wall of the box, as well as get the flat of the bracket level.

So I now have a toolbox for the 52-Set with a complete pair of interior brackets and wooden partition once again in place.

The next step for this part of the project now will be to figure out how best to fill in the screw holes on the exterior where the original filler hiding the countersunk screws has either fallen out or worn away a bit.


David

[David Dunlop]

I picked up this small tub of Glazing Compound the other day to be able to continue work on the Tool Box. From what I can determine from the three wooden boxes/cases forming part of the kit for the Wireless Set No. 52, the Cabinet Division of Canadian Marconi Company were using a product in 1944 called Glazing Putty to backfill the countersunk screw holes in these boxes/cases, prior to final assembly and painting. I can remember my Dad and Granddad using Glazing Putty in the 1950’s and 1960’s, when single pane glass replacements in a house were still common household practises and you could get small replacement glass panes cut at your local hardware store. From what I remember, the Glazing Putty back then was a soft, pale beige clay-like material sold in either pint or quart tins, and at one point even in heavy-duty clear plastic pouches. It had a smell of linseed oil about it and could be easily formed into pencil-sized strings one would press into the edges of the glass frame and shape off with your wet thumb into a nice 45-degree angle. The oil would be drawn into the wood of the window frame as the putty set up and you could then paint or stain over it with the oil based paints back in those days.

Seems that original putty has gone the way of the Dodo Bird today. A search for ‘glazing putty’ now turns up this stuff and all sorts of automotive body shop ‘bondo’. But I think this product will work out OK. Once any loose paint is removed from any of the countersunk holes on the toolbox, this product will fill and sand nicely. A new paint top coat and it should all look fine.

Getting this bit of work sorted out has also given me a chance to better understand how Canadian Marconi fabricated these boxes/cases back in 1944. There were definitely specific steps to be followed on the line. For example, all the countersunk holes had to be filled prior to any of the metal hardware being fitted to the exterior of the box, as some of the hardware overlaps these holes. I will post what I have figured out the line work was shortly.

This has also been an interesting exercise in clearing my head of all things ‘Sender’. I needed to step away from that part of the project to better understand what the issues with the Sender might, or might not be taking place.


David

[Bruce Parker (RIP)]

Dave, I just finished a complete window resto on our 1897 dated house. Glazing putty and me (plus the guy at the Home Hardware and his glass cutting table) know each other very well. My first few attempts at re-glazing went very badly but now I can do a smooth 45 degree putty job as good as the best of them (if I do humbly say so myself...).

Originally Posted by David Dunlop

I picked up this small tub of Glazing Compound the other day to be able to continue work on the Tool Box. From what I can determine from the three wooden boxes/cases forming part of the kit for the Wireless Set No. 52, the Cabinet Division of Canadian Marconi Company were using a product in 1944 called Glazing Putty to backfill the countersunk screw holes in these boxes/cases, prior to final assembly and painting. I can remember my Dad and Granddad using Glazing Putty in the 1950’s and 1960’s, when single pane glass replacements in a house were still common household practises and you could get small replacement glass panes cut at your local hardware store. From what I remember, the Glazing Putty back then was a soft, pale beige clay-like material sold in either pint or quart tins, and at one point even in heavy-duty clear plastic pouches. It had a smell of linseed oil about it and could be easily formed into pencil-sized strings one would press into the edges of the glass frame and shape off with your wet thumb into a nice 45-degree angle. The oil would be drawn into the wood of the window frame as the putty set up and you could then paint or stain over it with the oil based paints back in those days.

Seems that original putty has gone the way of the Dodo Bird today. A search for ‘glazing putty’ now turns up this stuff and all sorts of automotive body shop ‘bondo’. But I think this product will work out OK. Once any loose paint is removed from any of the countersunk holes on the toolbox, this product will fill and sand nicely. A new paint top coat and it should all look fine.

Getting this bit of work sorted out has also given me a chance to better understand how Canadian Marconi fabricated these boxes/cases back in 1944. There were definitely specific steps to be followed on the line. For example, all the countersunk holes had to be filled prior to any of the metal hardware being fitted to the exterior of the box, as some of the hardware overlaps these holes. I will post what I have figured out the line work was shortly.

This has also been an interesting exercise in clearing my head of all things ‘Sender’. I needed to step away from that part of the project to better understand what the issues with the Sender might, or might not be taking place.


David

[David Dunlop]

Most of the lower section of the content label that broke loose in the inside of the tool box lid survived as the three small pieces found in the bottom of the box when received. It is now time to glue them back in place.

I initially thought the original glue might have been mucilage but then realized that glue is always water soluble and the label would have been completely gone by now, had that been the glue used. Looking at some of the surviving glue, I now suspect Canadian Marconi used the same glue as they were using in their Cabinet Division.

I have decided to go with the Elmer’s Gel Glue for refitting the pieces of label. It is a water-based glue that stops being water soluble when cured. Being a gel it does not run and it has a nice working time so I can fiddle with tweezers for a bit to get the three pieces of paper properly placed before the glue sets up.


David

[David Dunlop]

The three label pieces are now back in place.

The exposure to moisture over the years has expanded the paper fibre enough that a perfect fit was not possible, but once dried, the sheen of the new gel glue matched up quite nicely with the surviving traces of wartime original glue still visible.

The smallest piece of the label turned out not to go in the bottom section but was a small part of the top left edge.

What I hope to do next with the tool box is carefully smooth down the blobs of modern NATO Green along the inside edges of the box and lid and give that edge a new coat of the original Flat Olive Drab. The rest of the interior will stay original.


David

[David Dunlop]

If you scroll back up to the photos in Posts #873 and #878, you will see a lot of blobs of NATO Green paint that had accumulated around the edges of the tool box and lid.

When this toolbox was given the NATO Green colour, it was likely in service with a 52-Set somewhere in the Canadian Army system and it was kept closed while painted. Excess paint on the brush got pushed into the seam between the lid and the box in a few locations and in some places even wicked along this seam before drying.

Some of this paint was quite thick and rough, but overall, about 80% of the original Olive Green paint had survived along these edges. The plan with all three wooden boxes/cases with this 52-Set is to return them all to wartime markings and the Olive Green paint, so I decided at this point to file down the blobs of NATO Green and give these two edges a fresh coat of the Olive Green.

In keeping with the overall plan for this 52-Set Kit to be restored to look ‘Gently Used and Well Maintained’, I tried to keep as many of the nicks, scrapes and gouges on the surface as practical.

Slowly, this toolbox is regaining some of its original look.


David

[David Dunlop]

I was finally able to pull my notes together and come up with a logical production process for the tool box at Canadian Marconi Company, taking into consideration they would have focused a lot on as simple a line as possible, that was cost effective and easy to understand.

All three boxes/cases manufactured for the 52-Set by CMC, along with the wooden case for the Coils, Aerial Tuning, are constructed of clear pine. Clear pine boards in large sizes are expensive. You can get around this, however, by getting pine boards cut in smaller sized boards and building them up to the sizes you need. Based on the construction details of the grey Spare Parts Box I found a couple of years back, one could see the tongue and groove details in the smaller pieces of pine used to build the larger panels making up the box.

So once you have a supply of the correct sized boards available, the wood requirement for one box becomes two matched end plates, two matched sides and a pair of top and bottom covers. The ends and sides would be sent through a finger joint maker to have the correct ends of each prepared for gluing and assembly.

The top and bottom boards both have 10 countersunk screw holes drilled around their edges. Two are on each end and three spaced down the long sides. The spacing is identical top and bottom. The most reliable, consistent way for Canadian Marconi to do that would be with some form of gang drill. A board would be inserted and held in place while the gang drill came down and drilled/countersunk all ten holes at once, fast and accurate. These boards would then arrive at the assembly point on the line where they would be glued and screwed down onto the four other finger jointed box panels that were being assembled.

At this point on the line, you would have a whole bunch of wooden boxes with very little extra information to go on. The two opposite sides with the 10 countersunk wood screws around the perimeter would be known as potential tops and bottoms, but fronts and backs could go either way. So in order to remove as much confusion as possible farther down the assembly line, the remaining sides of the toolbox must be readily identifiable. This could all be accomplished at a second well-equipped gang drill station.

At this station, an assembled toolbox would be loading onto the table, with either of the two panels with the 10 countersunk screws in it facing up. Once in place, one set of drills could be lowered to make the four rivet holes for the two hinge straps and the three rivet holes for the two handle brackets, thereby forever confirming the top panel with the 10 countersunk holes as ‘the top’. A second set of drills would come into the front panel and make the four rivet holes for each Latch Assembly and the three rivet holes for the bracket inside the toolbox that holds the tip of the soldering iron. A final set of drill would come on at the back of the box and make the four upper rivet holes for the two hinge straps and the countersunk hole for the machine screw that holds the large bracket on the back wall of the box for the hydrometer case.

At this point, all six faces of the toolbox can be clearly identified, which makes things a whole lot easier down the line.

The next stop on the line would be a band saw station where the box would be loaded such that the saw would be trimming off what will become the lid of the toolbox. Once the two parts are apart, drop the lid into its box and deliver both to the next station. This one took a bit of thinking, but the final clue was in the fact that two of the countersunk wood screws on the back edge of the lid, the countersunk machine screw holding the hydrometer bracket and the 6 finishing nails securing the interior wood partition all have to be filled and sanded down before any riveted hardware is installed, because some of those filled holes get covered with the hinge hardware on the back and lid. If you have to do that fill and sanding work at more than one station on the line, you are not going to be cost effective.

So I suspect that once the box and its lid were two separate items, the next station was where the wooden partition was installed using a spacer block to line it up. The three nails on the front and back of the box are all amazingly close to the centerlines of the edges of the partition. Easy to do with a little practice looking straight down from the top. The vertical placement front and back of each of the three nails are within about ¼-inch of each other. With the wooden partition in place, the metal hydrometer bracket could then be installed, using the top of the partition to get the bracket correctly squared in place.

Filling and sanding of all countersunk hardware could then take place.

There could be some variation in the sequence in which the riveted hardware was fitted, but while still on its own, it would be easy to install the soldering iron bracket and the two lower latch assemblies to the front of the box next.

The handle would be easy to do first on the lid, followed by the rivets securing the two upper latch sections to the front edge and the hinges to the lid. The last and trickiest riveting would be the ones securing the hinge straps to the back of the box, simply because you would now be dealing with working on one big item, in two parts, that want to swing about on the hinge straps.

After that point, the only hardware left to install on the box was the eight metal corner protectors (three round head, slotted wood screws in each), and filling the remaining holes on the hinges and latches with the same wood screws.

Then it would be off to the paint shop for an overall coat of paint inside and out and the addition of the stencil on the front panel. The List of Contents would then be glued onto the inside of the lid, the contents packed and the toolbox inspected and approved for packing.

The attached photos today show the bottom of the toolbox, the front, the top and the back, for reference.

While thinking about this box, I realized how wonderful it would be to find factory packing instructions for equipment like this. I cannot think of how many times I have looked into my Spare Parts Case for my 19-Sets and wondered how they were actually packed at the factory. I know all the bits are there, but it looks a mess and getting it all to fit and look right is yet to be accomplished.


David

[David Dunlop]

This Lamp, Operators No. 2 arrived safe and sound in this mornings mail from Holland.

With luck, it will form a key part of yet another sub-project in my overall Wireless Set No. 52 Project.


David

[David Dunlop]

With any luck at all, this collection of items, along with a few yet to be sorted, will all come together to create a working replica of the actual Operators Lamp for the 52-Set.

It seems the cargo ship full of all the originals has yet to be raised from the depths.


David

[David Dunlop]

I am not certain how many other 52-Sets might be out there being brought back into operational condition. It can be a challenge in terms of available information and every little bit helps.

In getting back to work on my Sender this weekend, I ran across a little oddity regarding the metering circuits in the 52-Set.

On Page 127 of the Operators Manual, there is a Table of Voltage Readings provided for the Sender. For HT1, depending on Sender Settings, the range of values is from 290 Volts DC to 310 Volts DC. This initially struck me as interesting, but odd. The upper scale of the 52-Set meter is from 0 to 300 Volts DC only. I then noticed the voltage range for HT1 stated on the Table in Page 127 was 0 to 600 Volts DC. If this information was correct, then when reading Sender HT1 values on the 52-Set Meter, the indicated values on the meter would have to have a ‘x 2 Factor’ applied to them, and the metering circuits would have to be set up accordingly.

When running a no load test of the Sender (no valves present), my HT1 reading was a solid, steady 150 Volts DC. Apply a ‘x 2 Factor’ and I get a perfect 300 Volts DC, which I was quite pleased with. I ran this information by Jacques Fortin and he checked the documentation and circuit diagrams. Sure enough, he found no evidence either of this metering design being mentioned in the manuals, and did confirm when the Receiver Meter Switch is on SENDER and the Sender Meter Switch on HT1, a pair of 600K resisters are brought into the circuit in series giving it a 600 Volt rating as per the Sender Voltages Table in the Operators Manual.

I am now going to start reinstalling the valves back into the Sender one at a time, starting at the front end of the block diagram. With all of them in place originally, one of the operational Tests for the Supply Unit had the two dynamotors running with 300 Volts HT1 just nicely, the next test up, however, had a massive load hit the dynamotors on startup and the indicator lamps nearly went out. And the HT1 reading was an alarming 180 Volts DC.

More as the saga unfolds.


David

[David Dunlop]

I pulled the Sender back out of the Carriers No. 4 this morning to install V6A, the Voltage Regulator and see what happens with the Sender when everything is powered back up.

Getting the Sender back into the Carriers No. 4 has always been a challenge, ever since it arrived. It wants to hang up at the last half-inch or so and ends up having to be pressed home in the upper left corner, and then wiggled some more to get the upper mounting bolts installed.

As I was swinging the Sender up onto my work desk and turning it around to install the V6A Valve, something caught my eye for the very first time with the PL2A 8-pt Connector mounted in the upper left rear corner of the Sender chassis. The MIC Terminal in the lower right corner of PL2A was bent upwards. So much so, in fact, that the corresponding Spade Terminal for this connection on the Carriers Plug was sliding underneath the MIC Terminal and pushing it upwards to the point where a crack had developed in the Bakelite body of the Connector, between the MIC and FAN Terminals. This is what has been causing the poor fit of the Sender in the Carriers No. 4, and who knows for how long.

The three photos today show the extent of the upward shift of the FAN Terminal and the crack to the left of it.

Now I just need to figure out the best cure for this problem, which will also successfully cancel any future travel plans for the crack that has developed. It does not look like it has caused any significant damage to this point in time.

I think I have said it before, but there is never a dull moment with this project.


David

[David Dunlop]

After studying the damage caused to the MIC Terminal of the PL2A Connector for a while, I decided a full disassembly of the connector was not necessary and that the terminal itself could be repositioned correctly with a little patient TLC. The trick would be not to try and fix everything at once by just trying to bend the entire terminal back down to where it should be located.

I started by inserting a medium sized slotted screwdriver head into the gap in the terminal and locking the blade up against the base of the terminal, directly below the round head slotted screw. Then I gently bounced the lower terminal blade a number of times until it was lined up with the others in the lower row of the connector. This left an excessively wide gap in the terminal, which then needed to be closed up by getting the upper terminal blade lowered somehow.

I found a combination of pinching the terminals together with my fingers and alternating with a pair of adjustable pliers worked well. After a few such pinches, I would have to stop and repeat the screwdriver move on the lower blade of the terminal to keep it back where it should be, but after about 20 minutes work of alternating the pinching and lower blade adjustment, I had the MIC Terminal looking just like a couple of the other terminals on the connector with wider gaps.

The proof was in trying to reinsert the Sender back in the Carriers No. 4 and this time it went a lot more smoothly than it ever has before. Getting it installed is now comparable to installing the Receiver and the Supply Unit, so one more unexpected item has now been fixed with this 52-Set.

In the attached photo, you can see how much better the MIC Terminal lines up with the other in the PL2A 8-pt Connector.



David

[David Dunlop]

The fact there are so many pieces to this project can be very daunting at times, but every once in a while this proves to be a blessing.

I have been spending the last few weeks focused on sorting out the Sender electrically. A strong part of this motivation is the simple fact I do not have a back up Sender assembly I can turn to if anything serious fails in the one I have on hand. Should that happen, I have a vey large paperweight sitting on my bench.

The second, related motivation is the fact I experienced a massive load hitting the Supply Unit when I first applied it in full power mode to the Sender, suggesting something was indeed seriously wrong somewhere, and that it was very likely in the Sender.

In the process of considering likely candidates for a problem in the Sender, I was looking closely at a couple of transformers as possible candidates this week and going through the Parts Lists to glean any useful information held therein. While doing so, I thumbed passed the two Rotary Transformers when a detail regarding the MG1A unit struck me. Its input rating was 12 Volts DC at 7.5 Amps. That prompted me to check its big brother MG2A directly below it. Its input rating was 12 Volts DC at 25 Amps. I was actually quite shocked, no pun intended.

I then checked TABLE VII, CURRENT DRAINS on Page 20 of the Operators Manual and there it was, 31 to 35 Amps in Low to Medium Power when the Sender was active in the Set. I had completely missed that point in getting overly concerned about potential problems with the Sender itself. I am currently running the 52-Set on just one CPP-2 Power Supply with a maximum output of 12 Volts DC and 22 Amps.

I am not that impressed with myself this morning, but still glad I discovered this when I did. Now to get the 2nd CPP-2 Power Supply I purchased from Brian Asbury last year paralleled into the system today and try again.


David

[David Dunlop]

When my second CPP-2 Power Supply arrived, I did a preliminary inspection and cleaning, tested it for working status, and that was it. I still have not yet performed a detail cleaning, but that will come in time. The important thing at this point was to ensure a close match in output between the two units. These power supplies come with a 6-position rotary switch that allows the supply to be set at various points between roughly 10 and 15 Volts DC. I was quite pleased I could get both of them sync’d at 13.5 Volts DC output to start.

The first photo has my original CPP-2 running with the amber indicator lamp and the new one with the red lamp. The second photo shows the input voltage at the Supply Unit after a short warm up.

The third photo shows the meter on the Receiver set to LT and reading a steady 12.0 Volts DC.

In the fourth photo, I have set the metering up to read the HT1 voltage being delivered to the Sender. This comes exclusively from the MG1A Dynamotor. Under a normal load condition in the Sender (all valves in place and not transmitting) this value would be 300 Volts DC. As you can see the meter reads a steady 160 Volts DC, which for the purposes of reading HT1 values, gets a ‘ x 2 Factor’ applied giving a no load value of 320 Volts DC, which is within the specified parameters in the manual.

The last photo is just a look at the full 52-Set idling with no load and its Supply Unit running perfectly in Send Mode. Something of a milestone moment after sitting idle for a number of decades.

Since the electrical testing I performed a few weeks ago showed no red flags up to the V7A (813) Power Amplifier, I am now going to recheck the Voltage Regulator V6A, and three 6V6G’s (V5A, V5B and V5C), the Master Oscillator Doubler, Amplifier Doubler and Intermediate Power Amplifier respectively, reinstall them in the Sender and run the Supply Unit again with them in place. Hopefully, there will be no surprises.


David

[David Dunlop]

A number of learning curves for the 52-Set are converging in my head at the moment and I am not certain I like it.

I have chatted with a couple of current users for the 52-Set and a former operator to learn what they have experienced and have been going through the manuals a number of times to wrap my head around it all. Interesting times.

One thing I have discovered is that there is apparently quite latitude in HT1 voltages displayed on the set for the Sender. The nominal voltage appears to be 285 Volts DC and one current operator with a Mains AC Supply has his running constantly at 285 and the set is quite happy. The manuals give a test range from roughly 260 to 310 Volts DC with a 10 to 15 percent variance for any given value as quite acceptable. Virtually all of my readings for HT1 fall into this range, which is challenging when trying to use the values for serious faultfinding.

Pin 4 circuits on the V7A (813) are still too high when the Sender is in RT Mode, but just fine in MCW or CW. Pins 1, 4 and 6 on V1J (ARP-3) in the Sender have a similar performance, so I am mapping these circuits out to identify all the connected components for a closer look.

In the meantime I have taken the Operational Tests as far as I could and so far and everything that is supposed to work and check out is doing so. I have also decided to run the NET and SEND Tests for a minute each, a couple of times a week. The NET gives MG1A, the 300 Volt HT1 Dynamotor a workout and sends electrons through those circuits. The SEND Test fires up both the MG1A and the MG2A Dynamotors thereby activating both the HT1 circuits and the 1,200 Volt circuits. So far, no loud noises, smoke or flames.

By the end of July, I will pull the Sender from the Carriers No. 4 again, pull all the valves, again, and retest the three odd circuits. I am curious to see if any of the bad readings will change, one way or the other. In the meantime I get a chance to do more reading and thinking.

In order to continue with the Operational Tests for the Sender, I need a Dummy Load to feed the 52-Set into. Turns out the 2nd to 4th Echelon Work Instructions provided a very nice diagram for constructing such a Dummy Load. The only risk was being able to find a 150 Watt Incandescent light bulb in todays world, but as luck would have it, the local Lowes still carries them I picked one up first thing this morning and now have an appropriate Dummy Load on hand to continue the Operational Testing. A good friend advised me his house still has several porcelain socket fixtures identical to the one in the original Canadian Army illustration but his wife nixed the idea of removing one and giving it to me, so I also picked up a modern, porcelain equivalent at Lowes.


David

[David Dunlop]

This item arrived in the afternoon mail today. Quite a bit of brown, Bakelite oxidation on it, which I have now polished off the right hand link in the first photo. Very easy to read the ZA 4444 VAOS Number on the polished link compared to the other two in the chain.

There is just one more of these to find now and I will have the set of five needed to replicate the 4-Section Horizontal Aerial used with the 52-Set.

An interesting observation with the photo of the group of three items with attached split metal links. Two of these chains also bear the ZA 4444 VAOS Number on each chain link. The third one, although virtually identical to the other two chains otherwise, has the Air Ministry Stamp on one side of each link, with ‘REF #10B/1275’, located on the lower half of the same side of each link in the chain. Clearly the Air Force and Army were using the same items under differing Stock Number systems.


David

[Chris Suslowicz]

Ah, I was going to mail you some of those at one point. (Me being absent-minded as per usual, sorry.)

Z1/ZA.4444 Insulator - 3-link chain type. (RAF Type 9) PC21061 10B/1275 10BZA4444 5970-99-105-3234
Z1/ZA.4589 Insulator - 2-link chain link, SD/A21073 5970-99-102-7930
Z1/ZA.4386 Insulator, Link - single link, SD/A23659 5985-99-103-2102

The ones with the split rings are probably for the stay assemblies on the 34-ft steel vertical aerial, though it originally used 'D' shackles so could be repaired without tools. (The split rings were a cost-saving/economies of scale measure.)

If you watch the WS11 station setup film from the Australian War Memorial site you can see just how complicated that mast was to begin with!

Best regards,
Chris.

[David Dunlop]

Hello Chris.

Hopefully, you are not on call tonight.

Negotiations for aquisition of the final needed 3-link chain would be greatfully undertaken, if you run across one looking for a good home.

I will have to recheck my photos of a 4-Section Horizontal Aerial for the 52-Set, but I think the two outer insulators had the split links to connect to the aerial masts as you stated. The inner three insulator assemblies were plain 3-links, being permanently fitted to the copper aerial wire sections. It will be another interesting sub-project when I get to it, and in all likelihood, will result in a subsequent discovery of a crate of NOS 4-Section Aerials complete with Reels, sitting in a barn somewhere.

David

[David Dunlop]

At the very beginning of this project, I had identified the following three items from my bins of 19-Set odds and ends as also being common to the Wireless Set No. 52. I had given them all a cleaning and overhaul shortly thereafter and put them aside until needed in this project.


KEY AND PLUG ASSEMBLIES, Cdn, No. 9, Type 2 ZA/CAN 0715
MICROPHONES, Hand, No. C3 ZA/CAN 1759
RECEIVERS, HEAD GEAR, MC, Mk 1 ZA/CAN 1638


This last weekend, I realized I will be needing the Key and Plug Assemblies very soon, as I continue to work my way through the Operational Tests for the Sender, so I dug them all out and ran tests on them all to ensure they were all in good working order. They all passed nicely and I am quite pleased.


David

[Chris Suslowicz]

Originally Posted by David Dunlop

Hello Chris.

Hopefully, you are not on call tonight.

Hope's been abandoned - I'm on-call all week!

Negotiations for aquisition of the final needed 3-link chain would be greatfully undertaken, if you run across one looking for a good home.

I've got a couple of boxes of them. I think if I send you three then you won't need to try and pry the split-rings off some of yours.

I will have to recheck my photos of a 4-Section Horizontal Aerial for the 52-Set, but I think the two outer insulators had the split links to connect to the aerial masts as you stated. The inner three insulator assemblies were plain 3-links, being permanently fitted to the copper aerial wire sections. It will be another interesting sub-project when I get to it, and in all likelihood, will result in a subsequent discovery of a crate of NOS 4-Section Aerials complete with Reels, sitting in a barn somewhere.

David

Somewhere I have the whole thing on its reel. I also have a 6-section version that must have been intended to replace the "wooden board set" for the WS19, but some of the lengths are way off specification and it would probably be unusable on some frequencies. The 6-section one has short (single link) insulating sections, like the later Aerial, 100-ft, No.5.

Best regards,
Chris.

[David Dunlop]

There goes your Beauty Sleep for the week!

Three would be perfect, Chris. I would then set the AM version aside as an interesting oddity. In truth also, I had been pondering how 80 year old Bakelite links would behave with somebody suddenly trying to wrestle those spring steel links off of them and suspected there could be casualties. I wasn’t keen on cutting the links either.

Better scoot. I am on the patio at the moment overseeing Honey BBQ Chicken Breasts on the Grill with Garlic Butter Baked Potato’s and a chilled Ale.

Best regards,

David

[David Dunlop]

If you take a look at the photo I posted earlier of the three Insulators (Post #893), you will likely notice the middle link looks fatter than the two outer ones in each assembly.

I noticed this when I took the photo but simply chalked it up to the lighting and angle at the time I took the photo. This morning, I was finishing cleaning up the assembly I had started and when doing so, noticed the middle link was indeed a lot thicker than the other two, so dug out my callipers to confirm.

Sure enough, in all the Insulator assemblies I have, the outer links averaged 0.320 inches thick while the middle ones averaged 0.394 inches. Otherwise, they are all dimensionally identical. So why the more robust middle link I wonder?


David

[Chris Suslowicz]

Originally Posted by David Dunlop

If you take a look at the photo I posted earlier of the three Insulators (Post #893), you will likely notice the middle link looks fatter than the two outer ones in each assembly.

I noticed this when I took the photo but simply chalked it up to the lighting and angle at the time I took the photo. This morning, I was finishing cleaning up the assembly I had started and when doing so, noticed the middle link was indeed a lot thicker than the other two, so dug out my callipers to confirm.

Sure enough, in all the Insulator assemblies I have, the outer links averaged 0.320 inches thick while the middle ones averaged 0.394 inches. Otherwise, they are all dimensionally identical. So why the more robust middle link I wonder?


David

The centre link is made in two pieces (with a peg and socket for location) and glued (I assume) together as required. I think it would be difficult to make the actual chain any other way, given the extreme pressure and baking required to produce the plastic. It also reduces the number of components to two: a complete link and a half link will cover production of the one, two and three link insulators.

Best regards,
Chris.