Wireless Set No. 52 Canadian - Project

[Bruce Parker (RIP)]

Often when you see a "C" in front of a number it is a 29 set part.

[David Dunlop]

Ah, Bruce. You have touched on another of the Great Mysteries in Life: Military Nomenclature. It never ceases to amaze me!

For starters, one practically trips over the letter ‘C’ in Canadian Army communications. In researching my 52-Set, I have seen communications between Canadian Marconi and the Canadian Army where Marconi identifies any wireless set they are referencing by its full name. In the return correspondence from the Army, these names invariably become,’C9’, ‘C9 MkI’, ‘C9 MkII’, ‘C52’, ‘C19’ and on and on it goes. One would think it was to denote the word ‘Canadian’ because the sets were designed and built in Canada, but they were still doing it in the 1960’s when the Plessey 42 Set came over from England for use in the Canadian Army and became the C42. But nothing about the 42 Set was ever built in Canada to my knowledge.

Then you have the British VAOS Directory, which adds a whole new spin.

Take this battery connector for example.

In a copy of the 1940 edition of the VAOS Directory I have, ZA 2270 is indeed a Connector, Single. But the similarity ends there. In 1940 it was a 12-inch cable of lighter gauge and the two end lugs were single hole items. Not at all like this heftier CMC product for the 52-Set.

The 52-Set Manual identifies this cable in the Parts Listings in the back of the manual as ‘Connector, Single #3 ZAC 2270’.

However, in the illustrations in the manual, this same part is identified as ‘Connector, Single No. C3’.

The 1945 and 1948 Master Parts Lists for the 52-Set both identify this part as, ‘Connector, Single No. C2A’ and make note that earlier ID of ‘Connector, Single No. C3’ should be ignored. No mention of the ‘#3’ version at all. But then to add insult to injury, this same part has a new VAOS Number, ‘ZA/CAN 4268’.

I am assuming the ‘C’ in all these part numbers probably refers to ’Canadian’ What I do not understand is if there is any real significant difference at all in the part if it has, or does not have the ‘C’ in its name. Usually, if something is changed significantly, it gets a brand new VAOS Number, and in this example, perhaps that is recognized by this heftier cable getting a new number moving from 2270 up to 4268.

One final stir of the waters with a stick.

The VAOS Directory is a British thing, with quite a long history. Typically, if you see a number like ZA 2270, it tells you it is a British Army part at the very least. What is not clear to me is what a number like ZA/CAN 2270 means. Is this an identical part manufactured in both England and Canada?

If so, then what relevance to parts do listings have such as ZA/CAN/BR 2270? If it started out being made in Britain, and then Canada got involved, why did they bother going back and mentioning Britain again?

Very confusing. But on the bright side, after reading the VAOS Directory for a while, I always feel like going for a drink afterwards!

David

[David Dunlop]

Just a bit of a way point in the continued direction of this project.

To recap this photo, the original dial to the Sender is the one on the left. All three dials look that bad. the one on the right is the one to be used on the Sender. It was off the Parts receiver.

The original dial is going to become a test bed of sorts. According to what I had read on electroplating, plating metal will not adhere to a cathode item at all if it is not meticulously clean. The existing adonized and painted dial has darkened somewhat over the years but is not that bad. the zinc plating around the rim and central dial plate is another matter. What I am curious about is what will happen if the rim and central metal are carefully cleaned back to good metal and I then electroplate the dial. In theory, no new metal should transfer to the painted section at all. Only the centre, back and rim of the dial, along with the four small rivet heads.

I am going to try it out and see what works and does not. It may be a useful restoration process for the other two remaining dials.

David

[Chris Suslowicz]

Originally Posted by David Dunlop

Ah, Bruce. You have touched on another of the Great Mysteries in Life: Military Nomenclature. It never ceases to amaze me!

For starters, one practically trips over the letter ‘C’ in Canadian Army communications. In researching my 52-Set, I have seen communications between Canadian Marconi and the Canadian Army where Marconi identifies any wireless set they are referencing by its full name. In the return correspondence from the Army, these names invariably become,’C9’, ‘C9 MkI’, ‘C9 MkII’, ‘C52’, ‘C19’ and on and on it goes. One would think it was to denote the word ‘Canadian’ because the sets were designed and built in Canada

The 'C' prefix was to denote Canadian design or manufacture because not all of the parts would interchange with the British manufactured set (if such existed).

, but they were still doing it in the 1960’s when the Plessey 42 Set came over from England for use in the Canadian Army and became the C42. But nothing about the 42 Set was ever built in Canada to my knowledge.

No, that is entirely different: they changed the set numbering system from the original "Single digit refers to its distance from the sharp end, 2 digits mean the first digit is the 're-design' level, second digit is the role, so you get WS1 = front line set, replaced by WS11, then WS21 (except it wasn't); WS2 replaced by WS12, WS4, 5 & 6 were progressively higher power (only 3 WS6's were built, one for Aldershot, one for Gibraltar, and the third for Hong Kong as the Army Communications Chain).

The "New Range" after WW2 classified sets by their input power requirements, from 'A' - man-portable, runs off dry batteries, through 'B' vehicle mounted, low-power; 'C' medium power; 'D' high power in trucks, and 'E' very high power (static).

I've got the actual figures somewhere... Ah, decided in 1947 as the earlier nomenclature was based on the tactical role:

A - 0 - 10 Watts Dry battery operated.
B - 10 - 100 Watts Low power secondary battery sets
C - 100 - 1000 Watts medium power sets
D - 1000 - 10,000 Watts High power sets
E - above 10kW Very high power sets.

The figures following represented the frequency spectrum and version of the set.

10 - 30 MF/HF band 3-30 MHz
40 - 60 VHF band 30 - 300 MHz
70 - 90 SHF/EHF band above 300 MHz

"Thus a set with an input of under 10 watts with a frequency average of 3-8 MHz and the fourth in its series would be designated A14."

Then you have the British VAOS Directory, which adds a whole new spin.

Take this battery connector for example.

In a copy of the 1940 edition of the VAOS Directory I have, ZA 2270 is indeed a Connector, Single. But the similarity ends there. In 1940 it was a 12-inch cable of lighter gauge and the two end lugs were single hole items. Not at all like this heftier CMC product for the 52-Set.

The 52-Set Manual identifies this cable in the Parts Listings in the back of the manual as ‘Connector, Single #3 ZAC 2270’.

However, in the illustrations in the manual, this same part is identified as ‘Connector, Single No. C3’.

The 1945 and 1948 Master Parts Lists for the 52-Set both identify this part as, ‘Connector, Single No. C2A’ and make note that earlier ID of ‘Connector, Single No. C3’ should be ignored. No mention of the ‘#3’ version at all. But then to add insult to injury, this same part has a new VAOS Number, ‘ZA/CAN 4268’.

I am assuming the ‘C’ in all these part numbers probably refers to ’Canadian’ What I do not understand is if there is any real significant difference at all in the part if it has, or does not have the ‘C’ in its name. Usually, if something is changed significantly, it gets a brand new VAOS Number, and in this example, perhaps that is recognized by this heftier cable getting a new number moving from 2270 up to 4268.

I think the renumbering happened when they split the UK and Canadian VAOS to avoid confusion. As far as I'm aware the 'C' in 'C3' just means Canadian manufacture, ZA/CAN, ZA/US and ZA/BR are used to distinguish the different catalogues, and there are parts labelled ZA/US/BR.nnnn (cable clips) where the item from either catalogue can be used because they're interchangeable.

One final stir of the waters with a stick.

The VAOS Directory is a British thing, with quite a long history. Typically, if you see a number like ZA 2270, it tells you it is a British Army part at the very least. What is not clear to me is what a number like ZA/CAN 2270 means. Is this an identical part manufactured in both England and Canada?

If so, then what relevance to parts do listings have such as ZA/CAN/BR 2270? If it started out being made in Britain, and then Canada got involved, why did they bother going back and mentioning Britain again?

See above.

Very confusing. But on the bright side, after reading the VAOS Directory for a while, I always feel like going for a drink afterwards!

David

The VAOS was originally "description, specification, and price" only. The numbers were added just before WW2 because it was getting out of hand and they needed to streamline orders. (This is why the early numbers are allocated in (mostly) alphabetical order of stores description - as you can see in the 1940 VAOS.)

Best regards,
Chris.

[Bruce Parker (RIP)]

Originally Posted by David Dunlop

I am assuming the ‘C’ in all these part numbers probably refers to ’Canadian’ What I do not understand is if there is any real significant difference at all in the part if it has, or does not have the ‘C’ in its name

Yes, the C probably denotes Canadian. But it's only so they'd know who to blame if the part broke.

[David Dunlop]

The Gloss Navy Grey finish coat on the Handles No. 72 and 80 had cured perfectly by this morning, so I was able to get the next step completed.

This involved reapplying the two red and blue Flick Indicator Dots to the face of the Handles No. 72. I decided to do this with a pair of the round, pointed end toothpicks one can buy at any Dollar Store these days, rather than attempting it with a fine point paint brush. The reasoning behind this was I would be able to have much more control over the amount of paint being applied and exactly where it would go. I felt a brush has a tendency to hold more paint than you expect and would be too flexible in such a confined space as a 5/64-inch hole.

It took a few tries to get a drop of paint on the end of the toothpick that was small enough to pass into the hole. Once ready, a steady hand is needed to insert the toothpick until it touched bottom. They you just slowly lean the toothpick to one side until the paint droplet makes contact with the side of the hole. It then instantly wicks completely around the hole. Straighten up the toothpick and remove it, and you are done.

Once this paint has dried, the next step will be to mask the marker slots on the Handles No. 72 and 80 and apply the flat white base coat paint to them.

David

[David Dunlop]

I was able to apply the flat white base coat to the four marker slots on the Handles No. 72 and the single Marker Slot on the Handles No. 80 this morning. It actually took more time setting up all the little bits of masking tape than the painting itself.

Hopefully tomorrow, I can start filling in the marker slots with the luminous red and green paints.

David

[David Dunlop]

If you check back to Post #513, you will see the original of this dial from my Sender on the left hand side. I had decided to use the spare dial on the right, from my parts receiver, as it was in better overall condition.

I also wanted to try out a test electroplating with this original dial to see how it would work out. The results are in.

In the first two photos today, you can see the original dial after I had cleaned all the metal surfaces with a brass wire wheel on my Dremel Tool. Once the bare metal was cleaned of all rust and other crud, I cleaned the entire dial with a general purpose cleaner and then rinsed it with Isopropyl Alcohol. This was followed by a light coat of car polish, on the black engraved face of the dial, to hopefully further prevent any plating from happening anywhere on it. Then into the electroplating solution it went for just over two hours.

When it came out of the solution, I was very pleased with the even plating around the rim, and once it had dried for about 20 minutes the central hub and rear of the dial looked pretty good as well. As it continues to dry out over the next couple of days, I expect the colour of the plating with lighten some more.

A couple of interesting observations. First, deposits of zinc did occur on the black engraved face of the dial, but only as very small dots of sand. When I rinsed it off in warm water after plating, these all washed away.

Second, the plating around the rim had a fine sandpaper feel to it. I was not sure if this would interfere with the smooth rotation of the dial in the drive assembly when fitted to the bottom of it, so I gave the rim a quick rub with a smooth cotton cloth. This got rid of the sandy feeling and I suspect the dial would turn with no problems in its drive assembly.

So I am now pretty certain I will use this process to refurbish the remaining two dial assemblies on the Sender. No choice really. I have no spares.

David

[David Dunlop]

The marker slots on the two handles have now been filled with their respective luminous green and red paints. The red paint is from a different supplier than the green I have been working with, but is also a thicker style of paint. Dries quickly and does not run.

Just letting them cure for 24 hours now.

David

[David Dunlop]

A good day today, and another milestone event in the largely mechanical so far, overhaul of the Sender. All the detail pieces for the Frequency MC Dial Assembly went back on.

A pretty straightforward bit of work, with the usual exception of getting the tab on the spring portion of the Bracket and Spring Assemblies No. C1 to pop back into its locking hole in the front panel. It is doable, but never yet have I been able to accomplish it without the tab cutting into the paint on the panel a little bit.

As I have mentioned before, this job is one to do with the Sender on its back so things stay put. The first parts back on were the front Clamping Plate and the small brass shim dropped over the central post. The large set of holes in the Clamp line up with the large holes on the drive and the smaller holes with the smaller threaded ones on the drive.

When you drop the dial itself in place, just make sure the three small studs in the central portion of the dial are on the side of the central shaft with the ‘flat’ cut into it. You will see a corresponding set of three holes on the bottom side of the Handles No. 72, the three studs on the dial will lock into. The two holes directly opposite each other hold the small pivot pins for the Clamping Screw Springs.

I put the Handles No. 72 face down on the bench and slide the two springs as far back into their slots as they will go. When I see the little central ‘V’ in each spring slide past the pin hole, I drop the pins in place. The next step it to get the inverted Handles No. 72 up off the bench and turned right side up without the pivot pins falling out.

What I do is take hold of the two ends of one of the springs with the thumb and index finger of one hand, making sure the spring ends are at the midpoint of the thumb and fingertips. Then close your thumb and finger so that the tips of each jamb in between the ends of the spring and the sides of the Handle. What this does is pull the spring against the pivot pin, locking it in place. Keep that tension on the spring and lift the entire Handles straight up, keeping it level.

Once you have the Handles above the bench, take the thumb and index finger of your other hand and rotate your wrist counter clockwise, until your thumb is behind your index finger. In that position, grab the other spring ends in the same manner as the first one putting the same tension on that pivot pin. While holding the Handles with your inverted hand, reorient your other hand on its spring so the thumb is also to the rear and reapply the tension on that pivot pin.

With both pins under tension now, you can turn your hands and the Handles right side up, align the flat of the Handle socket with the flat of the central shaft and lower the Handles onto the shaft until it is resting on the Dial. The Dial will now keep the two pivot pins from falling out and you can let go of the two springs. One last small step.

While holding the Handles to prevent it from turning, grab the rim of the dial with your other hand and turn it back and forth until you feel the three studs on it drop into the holes on the bottom of the Handles. The two parts are now correctly aligned. You can insert the central washer and mounting screw in the Handles now but only run it in about half way. And don’t tighten the grub screw yet either.

The odds are very good that when you install the Bracket and Spring Assembly, the rim of the dial will not automatically drop into its slot in the Drive Shaft, so by leaving the two screws in the Handles No. 72 loose at this point, you will be able to slip a small piece of wood under the dial and lever it into its slot. I use half of an old wooden clothes peg for that. Once that is done, the two screws can then be run home.

Once the Handles No. 72 is in place, you can install the four Clamping Screws. Start with the two Blue Indicator ones first. They are the ones that go into the larger pair of holes you noticed earlier. They reach all the way to the rear clamping plate assembly. When you feel the first of these two Clamping Screws catch the threads of the rear clamping plate, insert the second Clamping Screw directly opposite the first one. If you apply too many turns on the first screw, it will pull the Clamping Plate up at an angle and you will not be able to engage the second Clamping Screw. Once they are both engaged, tighten them and then back them off two full turns. This prevents a Flick Frequency being established in error. Then insert the two Red Clamping Screws in the same manner.

That is pretty much all the tricky bits that come with reassembling a Tuning Dial Drive.

Now I just have to repeat this process two more times and the Sender mechanical work will be almost finished.

David

PS: The toothpick in the photos was holding the Lower Flick Arm in place so it could be easily retrieved when it came time to inset the small lug on the end of the Tuning Drive into it.

[David Dunlop]

I finally got all the parts cleaned and/or refurbished for the I.P.A. 7 - 16 MC Tuning Assembly in the lower middle section of the Sender. And best of all, they were all reinstalled this morning.

This was the assembly I had originally noticed had a none working Flick Drive and once the front panel had been removed, found the Lower Flick Lever and the Spring connecting it to the Upper Flick Lever were completely disconnected. So now everything works with that assembly.

I just have the luminous paint details to reapply to the handles No. 72 and 80 for the PA TUNE Assembly on the right side of the front panel, and it will be ready for reinstallation.

David

[David Dunlop]

The parts for the PA TUNE Dial Assembly went back on this afternoon. This was the assembly that had a broken spring on its Bracket and Spring Assemblies No. C1 when I purchased the 52-Set, so the PA TUNE was totally none functional.

A fellow Amateur in the Maritimes donated a complete Drive Assembly as a replacement and that spring has now been put back to work on the Sender.

David

[Bruce Parker (RIP)]

Originally Posted by David Dunlop

The parts for the PA TUNE Dial Assembly went back on this afternoon. This was the assembly that had a broken spring on its Bracket and Spring Assemblies No. C1 when I purchased the 52-Set, so the PA TUNE was totally none functional.

A fellow Amateur in the Maritimes donated a complete Drive Assembly as a replacement and that spring has now been put back to work on the Sender.

David

Spectacular!!!!!

[David Dunlop]

Now that reinstalling the three dial assemblies has been completed on the Sender, I was also able to reinstall the three Knobs, Phenolic, Pointer on the set of switches across the lower right section of the front panel.

That just leaves the lock for the High Power portion of the Power Selector Switch to put back in the Sender. The lock is currently soaking in a small container of light weight air tool oil. A set of keys should arrive for the lock sometime this coming week. Much easier to leave the lock off the Sender until I have the lock working again.

David

[David Dunlop]

First thing this morning I went to the locksmith's and picked up the three keys they had made for me.

They were as amazed as I have become with the skills of the Illustrators CMC had on staff for creating all the drawings that went into the Master Parts List for this wireless set.

They discovered the Key Code was one of a series of about 1,500 that Corbin had assigned to some unknown contract. Very likely a military contract covering all the locks they had to make during the war. In addition, when they pulled up the computer image of the key code on their system, the key shape was a perfect match to the illustrations of the key in the manual I had sent them for reference.

David

[David Dunlop]

As I had noted earlier, the Lock Assembly has been soaking in light oil for the last week. It took two days to get all the air bubbles out of it, so after that I was confident all the interior bits were fully immersed. I knew the cylinder was moving in its housing and the bolt moved back and forth about a 32nd of an inch but was not at all certain what state of corrosion, if any had evolved inside the lock. When I got the Sender home, I had flooded the cylinder with DeOxit and followed that with 3 in 1 Oil, but that was the extent of any work done on it.

When I pulled the lock out of its oil bath last night, I was pleasantly greeted with a lot of very fine grey ‘dust’ coming out of the keyway and from around the cylinder. I took that as a good sign.

At the locksmiths this morning, they had one cut key ready to go to try out in the lock. If it was OK, they would cut the remaining two I had ordered. The key went in easily but alarmed us all briefly when it would not turn at all. The bolt was in its withdrawn position and the natural instinct was to turn the key clockwise to extend the bolt. We went to anticlockwise mode on a whim and instantly, the cylinder turned and the bolt extended. Learned something new about the lock today. It is a one half-turn mechanism. I am not at all certain when this lock last had a key in it, but I am thrilled it now has a set and the lock is fully operational once more.

The reinstallation of the lock into the Sender was relatively straightforward. The really nice thing is the Power Switch is very stiffly fitted to the chassis by its wiring so tends to stay put. The first step of installation was to slip the lock back into place. Then install the spacer on the lower right corner between the back of the lock and the switch plate, drop the screw down into it and attaché the star washer and hex nut, just a couple of turns, Then using a pair of long, needle nose pliers, I was able to reach in with the spacer for the screw located top dead centre on the switch plate and drop its screw down through it, thereby holding the spacer in place. Then you can go back and install the lower left side spacer, screw, star washer and hex nut. Tighten both of these about half way.

The top screw will now be lined up close enough to its captive nut on the top of the switch plate; you can engage the screw in its nut with a screwdriver and secure it. Then go back and tighten the lower two screw assemblies and you are done.

David

[David Dunlop]

I had to review my notes on the weekend to confirm I started the physical cleaning and restoration work on the Sender back on 01 March 2020. It seems a lot longer than that!

Here are a couple of photos of what I started out with, and a pair showing what the Sender looks like now. I honestly did not think I would even come close to having it look like it does now.

David

[David Dunlop]

Thanks for the kind comment, Bruce.

I have a little reno project to do in the Rec Room now, which will be a nice diversion. It will also allow me to think about what to do next with the 52s-Set.

David

[Jordan Baker]

Very impressive and wonderful restoration. Thanks for such detailed posts every step of the way.

[James D Teel II]

I always admire a master artist at work. Your work is above reproach.

[David Dunlop]

Jordan and James. Thanks for your kind words. Much appreciated.

Well…I tried.

I got the Mini Home Reno started the other day, and so far so good, but I could not keep my hands or mind off the 52-St Project. So, late this afternoon, I made some decisions and played with it a bit to plan my future actions with it.

First step will be to go back to the Main Set Receiver to finish off a few details. The luminous markings on all of the Knobs, Phenolic on it are still there, but either very tired, or worn thin. They all need to be reapplied and this can be easily done with the receiver still in place in the Carriers No. 4.

While looking at all these knobs, I realized the luminous markings on the Flick Selector, HANDLES, No. 80 was also in poor condition and the original Gloss Navy Grey paint was badly chipped and covered in aging varnish. It too will be brought up to snuff and this can also be done with the receiver where it is.

The last little bit of cosmetic work will be redoing the two KNOBS, Metal No. C1, the two knobs for pulling the receiver out of the Carriers No. 4. Their Gloss Navy Grey paint is also badly chipped and covered in aged varnish. The upper one can be removed by simply taking off the upper front panel of the receiver, but the lower one requires the receiver be out of the Carriers No. 4. I will probably approach this as a two separate blocks of work. Batch out all the Knobs, Phenolic first, then pull the receiver out of the Carriers No. 4 and do the other three items that require the same paint treatment work.

David

[David Dunlop]

The other thing I did this afternoon was I hooked up the 52-Set Power Cable to my 12 Volt DC Supply System and fired up my CPP-2. After 15 minutes, the CPP-2 was on its lowest setting and producing a steady 12.30 Volts DC output at the unit. The output still measured 12.30 Volts at the Supply Distribution terminals the 52-Set Power Cable was connected to, so that was all OK.

At the 52-Set Supply Unit end of the Power Cable, the input to the Supply Unit was reading 12.28 volts steady. I attribute that small drop to the shear size of the power cable.

When I turn the 52-Set on at this point, only the Receiver Vibrator Supply portion of the Supply Unit is active, running the receiver only. It hums to life OK and I waited another 15 minutes for the receiver to warm up. Audio output arrives in about 30 seconds or so. What is interesting, however, is the Meter Readings I am getting for internal voltages. HT reads 130 Volts and LT 10 Volts. The manual states the readings should be HT 150 Volts and LT 12.5 Volts.

If you recall, when I was running the two receivers with the ZE-11 Remote Supply, the meter readings for both receivers were showing identical, higher than stated values which we traced to the slightly higher output the ZE-11 was producing as a result of getting 120 Volt AC input rather than the 115 Volt AC it was originally designed to receive.

So my thoughts at the moment are the Main Set Supply Unit, Receiver Vibrator Supply section has some issues and will need a closer look. Fortunately, it is easily removed from the Supply Unit so can be bench checked rather easily down the road. While at that point running the set this afternoon, I turned on the Crystal Calibrator in the receiver. LT on the Meter dropped to 9.5 Volts. Stayed there after 15 minutes.

Then I turned on the Sender Heaters on the Supply Unit. This simply preheats the valves in the Sender, so it is ready to respond quickly when needed. LT Reading on the Meter dropped to 9.0 Volts for this and stayed there. Interesting. This will give me a good starting point on the project when the Main Set Receiver final detailing is completed.

David

[David Dunlop]

Over the last few days, there turned out to be enough lulls in the Reno Project, I was able to pull the five Knobs, Phenolic Pointer off the Main Set Receiver and refurbish them.

The first photo is them with the remains of the worn out luminous paints still in the marker slots.

The second photo is after they have been cleaned and the marker slots refilled with a new flat white base coat and new neutral luminous green paint.

The front three knobs look as if the marker slot paint is too wide, but that is just the camera picking up the fact those three knobs were closest to the UV lamp and were glowing that much brighter. Camera focus was somewhere closer to the back row of knobs.

David

[David Dunlop]

My initial thought with these four Knobs was to pull them off the Main Set Receiver to restore their luminous paint indicator marks, as per what I had done for the five Knobs, Phenolic, Pointer, but then I realized each of these four Knobs are held in place with two grub screws mounted 90 degrees from each other and that was an awful lot of fiddling with Bristo Wrenches.

Closer inspection further convinced me to leave these four Knobs in place when it became clear the marker spots on the front of each knob were actually drilled into the knob, as per the similar indicator marks on the caste zinc Handles No. 72. With the receiver out of the Carriers No. 4 and on its back on the work desk to remove the two KNOBS, Metal No. C1 for restoration, along with the HANDLES, No. 80, these knobs were in the perfect position to be worked on as well.

Only one of the four Knobs still had luminous paint at the bottom of its hole. The other three held basically just dirt. A 1/16-inch drill bit was the perfect size for cleaning up three of the holes. Twirling it back and forth in the holes with ones fingers worked a treat! The fourth and last hole, not so much. That sized bit was ever so slightly too large.

When I go around to putting a mirror behind the last Knob and comparing it to the other three, I finally noticed some casting marks on it, which were different from the marks on the other three knobs. Probably two different makers involved in production. So out came a large darning needle and with a little careful poking, all the dirt was successfully removed from this knob,

The two attached photos show the holes in the face of two of the knobs prior to any work being done. The second photo is the same two knobs after cleaning up the marker holes and adding in a drop of flat white base paint with a toothpick. As the paint dries this afternoon, it draws down into the hole and by later this evening I can follow up with small drops of the neutral luminous green paint to finish these four Knobs.


David

[David Dunlop]

With the Main Set Receiver now on its back on the work desk again, I was able to remove the Handles No. 80, Flick Lever Control, and the two heavy KNOBS, Metal, No. C1 that are used to pull the receiver out of the Carriers No. 4, and stuff it back in.

The upper KNOBS assembly came out nicely along with its star washer and 10-32 Hex Nut. The lower Knob, under the loud speaker took a little more work than it should have done.

Behind the front panel of the receiver, the lower KNOBS, Metal, No. C1 is used as a ground stud for an electrical circuit. It holds one of those teardrop shaped ring terminals on a wire lead. The type of terminal that serves as a lock washer. The 10-32 Hex Nut and the terminal came off the stud on the base of the Knobs assembly OK, but it took some coaxing to get the Knobs itself free from the panel. I have to take a closer look this evening.

The two Knobs and the Handle have now been cleaned and base coat primers applied to them all. With luck, and no snow tomorrow, they should be able to get their topcoat of Gloss Navy Grey.


David

[David Dunlop]

I was able to apply the final Gloss Navy Grey top coat of paint to the Handle and Knobs of the Main Set Receiver this morning.

They should be cured hard over the weekend and the luminous indicator mark can be reapplied to the Handles No. 80 and all three items reinstalled on the receiver.

David

[David Dunlop]

It certainly pays to review ones notes after a portion of a major project has been side tracked for a while.

I willed myself to do that last evening and it paid off!

The first thing I ran across was the need to get the AE Terminal on the front of the Receiver properly aligned so it points directly to the upper right corner of the FREQ. ADJ. Decal to the left of it. There is not much length in the connector between the Receiver and Sender to play with. I now have the trusty toothpick in place and reference point marked on the upper side of the chassis to adjust this Terminal. All three in the Wireless Set will then be correctly aligned.

The second thing I needed to do was buff down some sections of the two chassis bottom rails on the receiver, where rust had reached the point of small, crusty bubbles, and some corresponding rust bubbles on the floor rails of the receiver compartment in the Carriers No. 4. Things need to be as smooth as possible to slide well on that nasty gloss NATO Green paint that got slathered all over the inside of the Carriers.

There was also a small inward bulge in the upper left side of the Carrier left side panel, near the upper bolthole. It made things potentially snug, so a few gentle taps with a 5 lb. mallet dressed that back nicely as well.

So far so good.

David

[David Dunlop]

The bottom chassis rails on the Receiver are now cleaned of all the lumpy rust and should slide quite nicely now in and out of the Carriers No. 4. Fingers crossed anyway…

Also managed to get the Terminals Aerial No. C1 on the front panel correctly oriented.

David

[David Dunlop]

It appears as though the problem I was having getting the lower Knobs, Metal No. C1 off the front panel of the Receiver was a result of it not being reinstalled correctly the last time it was removed.

The upper Knobs assembly was just fine and it is the one on the receiver that mounts directly to the lower front panel plate by means of an external tooth lock washer and 10-32 hex nut.

The location of the lower Knobs assembly places it where the lower front panel mounts directly over the front portion of the lower chassis box assembly. The row of six toggle and rotary switches running along the lower section of the Receiver are all mounted directly to the front of the lower chassis box. Holes are punched in the lower front panel plate to allow this plate to clear the hex nuts holding all these switches in place.

Because the lower chassis box is directly behind the front panel in this area, the designers at CMC threaded the hole in the lower chassis box so the 10-32 stud on the base of the Knobs, Metal No. C1 can thread directly into the chassis box for maximum strength when pushing and pulling the Receiver in and out of the Carriers No. 4. When this particular Knob assembly was last installed, it was not threaded all the way flush to the front panel by hand. There was a small gap left. When the electrical grounding terminal was attached to the stud of the Knobs behind the chassis and that hex nut run home, it ended up pulling the Knobs down flush with the front panel on the outside, but in the process of doing so, the threads in the metal of the lower chassis box plate were pulled inwards, When I now tried to remove the Knobs, the bent threads were binding on the stud of the Knobs assembly. A quick in and out with a 10-32 Tap and the problem was solved.

With the two Knobs now reinstalled and the Handles No. 80 refurbished, the Receiver finally looks like it belongs with the Sender.

I am going to take advantage of the Receiver being out of the Carriers No. 4 for a while and run some tests on it again with the ZE-11 Remote Supply.

David

[David Dunlop]

It pays to keep detailed notes during a restoration project. It pays dividends to actually review them!

I have been trying to wrap my head around the reason why the Supply Unit would have such a significant voltage drop feeding the Main Set Receiver, assuming that simply because the Supply Unit is the new kid on the block, the problem must reside with it. I decided over the weekend to confirm that theory by pulling the Main Set Receiver from the Carriers No. 4 and firing it up with the ZE-11 Remote Supply Unit.

Surprise! Surprise! Same poor readings with the ZE-11 running the show. So out came the Remote Receiver and I hooked it up to the ZE-11. Perfect Meter Readings on the Remote Receiver and the signals came booming in over my 134-foot dipole. I had both the RF and AF controls at maximum and had to quickly dial the AF back about half way to get a nice listening level. Even the built in Crystal Calibrator signals were easily heard. No signals of any kind to be heard on the Main Set Receiver. Then the cobwebs slowly began to fall away and I remembered my notes.

I started working full time restoring both receivers exactly two years ago today and was working on them regularly up until near the end of July, early August 2019 when word of a possible complete 52-Set surfaced somewhere in Montreal, and the rest was history.

Digging a little more deeply into my notes I remembered I had finally got the Remote Receiver up and running very nicely, and the next step for it was going to be an actual alignment and calibration. The Main Set Receiver, on the other hand, had only reached to point of taking electrons through it completely, but not very well. The biggest issue with it was poor HT and LT voltage readings in it. My plan at that time was to start a detailed trace of the circuits starting at the incoming 8-Pin Connector and tracing what went on, using the Remote Receiver as the ‘Benchmark’.

So the odds are now saying the Supply Unit in the carriers No. 4 is probably in good working order, but needing a good cleaning up. A quick check of the +12 and +150 voltages at the Receiver Connector in back of the Carriers No. 4 next time I pull the Receiver, should confirm that point. My thought is the Main Set Receiver now needs to be brought back to good working order. Once it is able to pull in good clear signals, especially its own Crystal Calibrator, I can eventually use it with confidence when time comes to try tuning the Sender to it.

David