Wireless Set No. 52 Canadian - Project

[David Dunlop]

Hi Chris.

Downloading the 2/4 EMER for the 52-Set is on my Must Do list Monday evening when my 2 week probation is up. I have the equivalent 19-Set publication which also covers the same Flick Assy and I know I have disassembled quite a few on the 19’s years ago. I used that publication as my reference and ‘I think’ it covers reassembly, but it has been a while.

With regards to the Connector on the rear of the receiver missing its R-Clip, if you have spares to spare that would be a big help. Thanks.

I must revisit my parts bins again soon. I am sure I have other items tucked away, but cannot recall what. Never know what common items from the 19-Set might fall out of a bin and be shared with the 52-Set.

David

[David Dunlop]

A couple of Sunday morning observations.

It appears these receiver chassis were inspected at a standard inspection station that used a steel stamp punch to verify the inspection. I have found this 5/16 inch stamp on the outer left and right chassis side panels on both the main set receiver and the remote receiver. these two units are roughly 2,000 apart by serial number in Marconi's 1944 production.

The other interesting discovery relates to the Crystal Calibrator chassis in the upper left corner of the receiver. If you check back at the photo in Post #4, you will see a large daub of blue paint on the calibrator chassis at the left end of it. I found the remains of a similar daub on the Remote Receiver calibrator chassis.

This mark was applied at the factory to denote that all the valves in the calibrator have been 'aged'. That means they have been run for 12 hours to ensure the electrons will feel right at home in the valves when they are put to work. In addition, the receiver manual notes that Marconi has aged all essential and spare calibrator valves issued with the set. These valves have also been marked with a blue dot of paint on the end of the locating pin.

Whenever a valve has been replaced in the calibrator, the calibration test needs to be performed. With an aged replacement valve, this test can be done straight away. If the valve has not been aged, the calibrator needs to be run for 12 hours before the test can be performed.

David

[Chris Suslowicz]

Originally Posted by David Dunlop

With regards to the Connector on the rear of the receiver missing its R-Clip, if you have spares to spare that would be a big help. Thanks.
David

Consider it done.

Looking at the photo of the broken screw, I suspect the culprit attempted to undo it using a screwdriver. This is a mistake, as all the screw slots are in-line with the contact slot (twisting the screwdriver would deform the contacts) and the obvious assembly/disassembly method is with a box spanner or nut spinner on the rear of the connector. (Also the nuts are sealed with varnish, so may be very hard to undo without applying a suitable solvent (or heat) first.)

Chris.

[David Dunlop]

Thanks, Chris. Much appreciated. PM me if you need my address.

I was wondering about that broken screw as I could see they were visible inside the clips, but a screwdriver would have to be forced into the clip to access the screw, which struck me as a very unfriendly thing to attempt to do to the clips.

You have now confirmed my suspicion that the back door to the Connector Plug is the best avenue of approach.

David

[Bruce MacMillan]

When I restored my Canadian Marconi CM11 I noticed it used the same connectors. Males were on the cabinet back & females on the equipment.

Jerry Proc restored the same equipment on HMCS Haida and may have or know of where spares may be on your side of the pond. http://www.jproc.ca/

[David Dunlop]

A nice surprise today. I was giving the innards of the Remote Receiver a closer look and a bright, shiny object suddenly caught my attention. It was the Gas Filled Discharge Gap that was missing from its clips at the Aerial terminals, stuck between two of the calibrator valves.

Cleaned it off and took the attached photo before clipping it back into its proper place. It measures 2-5/16 inches long and 7/16 inch diameter at the caps. The only markings on it are "PATT. 3841" stamped into the sides of each end cap.

David

[David Dunlop]

While giving a closer look to the Remote Receiver today, a piece of beige paper revealed itself trough a circular hole on the left side of the chassis. While looking at it, I noticed a pattern of four screws, above and bracketing this hole. I had seen that pattern before and it took a while to register exactly where. It was on either the side, or rear B-Set chassis plate on my 19-Sets. It was a Modification Card Holder and this one on my Remote Receiver clearly held a card.

I was delighted when I removed the card to find it confirmed the Serial Number of the Remote Receiver as being '7746'. Three modifications were done to the receiver on 10/03/61 (I can never remember the Military Day/Month sequence on these things but interesting the work was done in 1961).

'F257' is probably the reference code for the 52-Set Cdn, and if that is correct, at least six modifications exist and the three noted relate to the receiver.

This prompted another look at the Main Set receiver. Sure enough, the Modification Card Holder was there, but I could not see a card initially. However, when I shone a flashlight down into the top of the holder, I could see something was there. This resulted in a quick raid of my lovely wife's sewing room. A possible tool was found. A return to the receiver and an insertion of the tool pulled out a modification card. (Who knew a crochet hook could be so handy!) A different pattern mod card than the other one. Much stiffer paper and when folded over in the holder it stayed put. Interestingly it shows the chassis Serial Number to be '8356', as opposed to the plate on the front of the receiver being '8349'. At the moment, my gut is going with the Mod card. It was firmly in place in its holder and invisible. More likely the data plate was replaced or the entire upper front panel of the receiver.

Only one modification was performed on this receiver on 01/12/52 - F257/#1.

Be interesting to find a record of these modifications.


David

[Wayne Hingley]

Originally Posted by David Dunlop

...Three modifications were done to the receiver on 10/03/61 (I can never remember the Military Day/Month sequence on these things but interesting the work was done in 1961).

Nice couple of finds David. I believe the date format is dd/mm/yy. That was the format used on the RCEME engine rebuild tags anyway (at least the ones I have seen).

[David Dunlop]

Does anyone have an original condition Carriers No. 4, or Remote Receiver Case in the No. 2 Brown colour?

My Remote Receiver case has been refurbished in postwar NATO Gloss Green, and was completely painted inside and out. I am curious if these two items were completely painted, inside and out, at the time of manufacture, or if the interiors were only painted as far back as the overhang that protrudes beyond the face panels of the main components.

And while I think of it, was the C-Broad Arrow stamp applied anywhere on the outside of these two items? And in what colour?

David

[David Dunlop]

Thanks for the date confirmation, Wayne.

On looking at the two Mod Cards again, I realized two different numbers were referenced: F527 and F257. One of those has to be a brain fart.

Looking at my two receivers over the weekend, I have decided to focus first on restoration of the Remote Receiver. Foremost, it is electronically intact and also cosmetically very good looking. The chassis will need a cleaning and an inspection/testing of all valves and should then be ready for a careful feeding of electrons. The case needs a few repairs but they can wait until I get the correct painting information sorted out. I will also benefit by becoming more familiar with the receiver chassis before I have to tackle the more serious switch damage repairs in the Main Set Receiver.

I was able to download and print out a copy of the Parts Identification List for the set on the weekend. An absolute goldmine of information for a project like this.

David

[Tim Bell]

Epay - not mine... ws52 remote receiver psu...

https://www.ebay.co.uk/itm/WW2-Canad...wAAOSwDFBaS4UL

[David Dunlop]

Thanks, Tim. I will check it out.

David

[David Dunlop]

Well I have found another receiver this past week that will be serving as a parts doner for my Main Set and Remote Receivers. It is complete but has been in a humid location somewhere just long enough to build a bit more surface rust on the chassis than is worth dealing with. Also, a number of key decals on the front have been badly damaged/chipped away. Not a choice I take lightly, but other events this week led me to conclude it was a wise decision.

I started to clean and visually check the valves on the Remote Receiver, starting with V2B, the 12Y4G Noise Limiter. I chose that one as it was missing it's shield cap and I now had a replacement from the doner receiver. You can see this valve in Post 37, horizontally mounted, mid rear chassis.

First thing I discovered was this valve is the only receiver valve that does not have any physical locking means to keep its shield assembly in place. Consequently, Marconi sweat soldered the base of the shield to the valve socket and coated the solder seam with clear red lacquer. Marconi appears to have used this lacquered solder technique throughout the 52-Set Receiver chassis. This valve is the most difficult to get at on the chassis and it takes a bit of wiggle to remove it from the shield. When it was out, I realized the top of this particular shield was different from others I have encountered. The top edge is straight cut, not rolled in, The rolled in approach makes for a very firm shield top that a cap can be pushed over very easily. Not so the straight cut edge as a close look showed several dents and bumps around it. Which explained why the cap was missing. Back to Debbie's jewellery supplies for her small, smooth faced, needle nose pliers. After nearly 45 minutes of bending, tweaking and muttering, I finally had the edge of the shield smooth enough to accept the cap. Then the second problem smiled at me.

The 12Y4G has no central key post on its base. It relies on proper seating in the socket by the pattern of spacings of the pins, No big deal for a vertical installation with no shield to deal with. Very big deal in a horizontal mount with a fixed shield obscuring any observation of the process. I ended up staring at the bottom of the socket at the back of the chassis, with a flashlight in one hand while the other twiddles the valve, which I hoped was at least starting out in somewhat correct orientation. Only took 10 minutes.

Extra valves on hand are going to be a definite asset with this project!

David

[David Dunlop]

I joined the wireless-set-no19 Group in the UK at the beginning of the year, on the suggestion of Chris Suslowicz. They have a very good reference library members can download from.

Found the 52-Set Modifications. Only 6 issued. The first one, of course, was where and how to install the Mod Card Holder on all the 52-Set components. Number four was also interesting. How to prepare the set for Arctic operations. And the fifth mod was for the removal of the pocket watch holders which were to be thrown out as the watch had become a redundant item.

David

[David Dunlop]

In January of 1945, the Canadian Army published their EME Instructions (Telecommunications F254/3 ) for the Wireless Set Canadian No. 19 Mk III. This is a very lengthy tome, which goes into beautiful, well illustrated, procedures for the complete testing, disassembly, repair and reassembly of the Cdn 19-Set Mk III. It even lists all of the test equipment required to do the work.

I would like to determine if the Canadian Army every produced an equivalent publication for the Wireless Set No. 52 Canadian. Has anyone ever seen a copy over the years?

I am planning to contact the Signals Museum in Kingston to see what they might have in their archives. It would be a great help, (if the publication actually exists) to know its Telecommunications Reference Number and when it was first published. Would not be a surprise if updates came out in the 1950's as well. They certainly did for the aforementioned 19-Set Instructions.

Thanks,

David

[David Dunlop]

Another week. Another adventure.

As I had mentioned earlier, I want to first focus on getting the Remote Receiver back up and running. There do not appear (so far) to be any electrical issues. Most work will be cosmetic and physical in nature. However, at some point I am going to have to chase electrons into it and see what they get up to. Towards that end, a huge piece of the project arrived last week…a ZE 11 Remote Supply Unit.

I had known about this item for a while, but was also aware it related to the Wireless Set No. 9 Mk. I Cdn. The ‘correct’ Remote Supply for the WS-52 is actually the ZE 12. Then I learned from Jacques Fortin, out Quebec way, that there are only a few minor component variations between the two supplies and in fact Marconi had shipped ZE 11’s with initial production of the WS-52, until production of the ZE 12 was ramped up. So I bought this ZE 11.

Externally, the supply shows the usual dirt and nicotine accumulations for its age, but overall the original wrinkle green paint and white silk screened markings are in excellent condition. The underside of the cover assembly is finished in a very fine textured silver/grey metallic paint. I am curious now if this finish was also applied to the interior of the main set carriers and the remote receiver case.

The OZ4 looks a bit scruffy and has not yet been tested. The Serial Number (3892) has been stamped on a small metal plate which was then riveted to the top of the Choke cover, over top of the white stencil that notes a location for a serial number. I am wondering if initially these supplies just had a painted on serial number and then later Marconi switched to a metal plate format to extend the life expectancy of the identification?

The outside top of the cover has the number ‘3820’ hand written in white on it in two separate locations. Possibly a cover from a doner supply.

The AC cord is original, measuring about 7.5 feet. It had electrical tape wrapped around it a couple of inches above the base. At first I though this might be hiding a splice, but a closer look indicates a rodent of indeterminate size appears to have used the cord as dental floss at some point. I will have to take a closer look at that later.

In any event, it seemed the right idea to get this supply checked out and working as the first part of getting the Remote Receiver back up and running. Same initial goal, just a slightly different start point.


David

[David Dunlop]

With a bit of free time to play with this morning, I decided to dive into the AC Cord repair on the ZE-11 Remote Supply.

I assumed there would be two main parts to this work: a physical part dealing with the placement of the cord, and, an electrical part dealing with the usual desoldering and soldering of the two cord connections wherever they happened to be.

The first step was to remove the base plate from the supply. Straight forward enough. 12 small round head, slotted screws with lock washers, three per side. 11 screws were found to have the split lock washer style, the last one an internal tooth lock washer. Easy enough to eventually upgrade the latter to the correct style. Nice surprise inside the base plate. A very minty, lacquered circuit diagram for the supply.

After admiring the diagram for a few moments, I had my first reality check. Things can get quite crowded inside this equipment! It took a moment or two to confirm where the ac cord entered under the chassis. I had hoped the anti-strain devise used on this cord would be a simple knot tied into it to limit movement of the cord back out from under the chassis. Nope! This little puppy was held firm with a small ¼ inch clamp. Roughly dead center in the photo, you can see the small hex nut securing the clamp. Just to the right of the C22A Capacitor next to the ‘22’. Once you spot the nut, the clamp curve is quite evident with the two sections of heavy ac cord looping out. One lead ran straight to a pin terminal on the AC Selector Socket. The second shorter lead went up to a terminal on the 115V/230V Selector Switch.

Fine so far.

Step 1: Lets free up the AC Cord so the 4 inch damaged section outside is now inside where it can be removed and enough new, solid cord used to reconnect everything. The crowded conditions are really starting to make an impression on me now. The hex nut and visible screw securing the clamp are tucked under the C22A Cap just enough that I know removing the nut with a ¼ inch socket should be OK, but getting the nut and supporting lock washer back in place from underneath the chassis will be the tricky bit. Best check how accessible the screw is from top side. Of course. No visible screw topside!

A few careful measurements later, I discovered the screw used to secure the AC Cord Clamp is actually one of the screw posts fitted to the Transformer Cover on top of the chassis. That pleased me in so far as having figured out the transformer, choke and their respective covers must have been added to the chassis at, or just before, the AC Cord was fitted. But that did not cheer me up too much when I realized just how much more wiggle room the assembly line worker at Marconi must have had, compared to myself, when working on this part of the assembly.

In any event, out came the appropriate sized ¼ inch socket and off came the hex nut. Some careful use of a set of needle nose pliers, and out came the nut and the lock washer, followed by the clamp.

David

[David Dunlop]

Note to self: Find the stainless steel surgical clamps you bought years ago from Princess Auto. I bought them when working on my 19-Sets because they are brilliant for fishing loose bits like nuts and washers out of cramped chassis areas.

So I now had the AC Cord free to feed back down into the chassis area. I checked the Parts Listing for the ZE-11 and the factory cord is 8 feet in length. I needed to move just over 5 inches inside to get rid of all signs of rodent flossing and end up with actually more cord to work with when resoldering the two connections.

I was able to get the cord laid out and the clamp back in position easily enough and the clamp ended up on the screw post with just enough screw exposed that the lock washer would stay put on it. But how to get the hex nut back down squarely on the screw to feed it onto the screw? No finger room at all. I knew I had done this sort of thing before in working on my 19-Sets. A cup of tea later and it all came back to me.

Two options I had used in the past depending on how much access I had for a socket to fit.

If there is not enough space for a socket to safely start the hex nut home, without risk of an angled approach cross threading the nut, I used to use a pencil, piece of dowel, or similar item. Take the flat end and attached a tiny square of double sided tape. Then press the hex nut squarely on the end. Line it up square with the screw and slowly start turning. You can tell right away if the nut is threading its way home and the nut will simply twist free of the tape when the time comes. You can then safely fit the socket to the nut to finish the tightening process.

Alternatively, if you have the space to use a socket head. Pack a bit of tissue paper or paper towel into the opening of the socket head you need to use. Follow that with a small ball of plasticine, plumbers putty or that grey window putty used to seal window seams in the Winter. Then press the hex nut onto the putty. It will stay put while you turn the socket around to install the hex nut. Any putty that sticks to the nut when you are done is easily wiped away, and you can just poke a nail into the back side of the socket to push the paper plug back out. The paper cleans the putty out of the socket and away you go.

Turns out all this was the really easy bit. As I was starting to unsolder the AC Cord from the AC Selector Switch terminal, my 40+ year old soldering iron died. As it’s final farewell, it revealed just how the connections were made to this terminal and it was not what I had hoped for at all.

This will continue once I have sorted out a brand new, variable temperature soldering station and a fresh supply of desoldering braid.

David

[David Dunlop]

While rummaging through some more wireless bits boxes on the weekend, I rediscovered an old project package I had abandoned umpteen odd years ago, Trying to put together the really good parts from several Key & Plug Assemblies No. 9 Canadian, to make a good one for one of my 19-Sets. I think I stumbled across a very good assembly at a local sale and work on the project halted.

As it turns out, one of these Key and Plug Assemblies is needed for the 52-Set, and since I cannot do any soldering until my new soldering station arrives, I decided to reactivate the work needed and put a Key & Plug Assembly together for the 52-Set.

The project was simple enough, involving the transfer of the plug and cord assembly (in good condition) from a scruffy unit somebody had cut the leg straps from, to a very good unit somebody had cut the plug and cord from.

There are only two things that are a bit tricky about the work needed to be done: the two terminals on the positive and negative cord leads are crimped to the leads AFTER the cord is fed through the grommeted opening in the key base plate at the factory and they are too wide to slip back through the grommet as is, and secondly, there is an anti-strain loop woven into the cotton cord loom that slips over a J-Post Bracket at the back of the key bar assembly, just inside the case, This cotton loom is now some 60+ years old and is often not up to liking a lot of pulling and tugging, without breaking.

Step one is to remove the two terminal screws for the positive and negative leads. Make note the negative (earth) lead is the front most one. It has green cord wrapped at the base of its ring terminal and a green tracer woven into its loom. The line directly behind it is the positive one, with a red cord wound at its terminal lug and a red tracer woven into its loom.

Once you have removed the two leads from their terminals, remove the terminal screw on the back of the J-Post. It is only there to secure the anti-strain loop that has been slipped over the post. You will have to feed about one more inch of the plug cord into the key assembly at this point to give yourself enough loose cord for slipping the anti-strain loop off the J-Post. Once it is free, you just have to deal with the two terminal ring lugs.

The best way to remove the two leads is to hold a ring terminal with a pair of pliers, on one side of the lug, about one third of the way across the ring, Then take another pair of pliers directly across from the first and GENTLY and SLOWLY bend the ring to form a gradual, near 90 degree bend. You just want the diameter of the ring to have reduced enough to slide out through the metal grommet. Do the same to both ring terminals and you should then be able to remove the plug cord from the key assembly. Best to do it strain loop first and then one electrical lead at a time.

Reverse the process into the good key assembly. Insert enough cord that you can easily slip the anti-strain loop over the new J-Post and then gently snug it back. To reflatten the two ring terminals, I use a pair of needle nose pliers that have a smooth inner face to the jaws down near the jaw pivot point. Or, I sneak a pair of Debbie’s jewellery pliers that have smooth faces to do the job.

A couple of other points on these Key & Plug Assemblies. I have seen them with and without the bakelite guard fitted to the key bar, under the bakelite knob. I am not sure if this is just a case of these guards sometimes ‘disappear’, or if it reflects a change in production, with early morse keys lacking the guard and it being added later. No big deal if you never plan to use the key, If you do plan to use the key for CW work on a restored wireless set, I highly recommend you find a guard and install it.

Ever noticed the funny looking bakelite finger guard surrounding the morse key socket on the Mk III 19-Set? It is usually not there on the Mk II Set, which normally has either nothing, or a simple flat rectangular bakelite plate around the socket.

When you are working CW on a wireless set, the Send and Receive functions are controlled by the key plug. Fully inserting the plug places the set into transmit mode, pulling the plug half out of the socket places the wireless into receive mode. In Receive mode, one half of the brass plug assembly sits exposed outside the front panel of the set. If the wireless operator is in a hurry to transmit and pushes the plug back in with his fat fingers in the way, he will find full transmit High Tension power arcing into himself very quickly. Hence the development and installation of the finger guards. And the guards are great, but not perfect. The one on the Morse Key Bar and the knob will only protect you for the first 8 Amps. After that you are on your own.

Wonder how many wireless operators had their key strapped to their thigh first thing in the morning and spilled their cup of tea on their lap? Be more than their Rice Krispies going ‘Snap, Crackle and Pop’.

Hope this wan't too long winded.



David

[Chris Suslowicz]

Ah, you're fitting the cable backwards!

Replacement cables would be supplied with the appropriate tags on both ends, the key end would be attached first, and the cable fed through the grommet, after which the jack plug would be fitted to the free end. Workshops (ant telephone exchanges) had a hand-cranked jig to assist in screwing the jack plug on to the (ready made) cable, after which the crimped-on terminals would be fixed to the plug connections and the plastic cover screwed home.

I'd like one of those jigs, as I have replacement switchboard cables (in Chinese Red only, so far) to restore my Switchboard UC and its severely moth-eaten cables with.

Original British keys used the No.10 plug, which provided adequate finger protection. The Canadian keys had a more exposed 'hot' end, and the set was fitted with a plastic guard to reduce the risk of a 'belt' from the buffer stage HT (250 volts or thereabouts). I can't remember what the American keys used.

'Ham' modifications using commonly available jack plugs are a recipe for disaster if used by the unwary: Post Office style jacks with exposed screws (and the tail end of the brass body) are a hazard, and I hate to think of what the modern "all metal" screened plug would do to the user!

Chris.

[David Dunlop]

Hi Chris.

I’d prefer ‘Reverse Engineered’ rather than ‘backwards’.

Thanks for the assembly background. I didn’t realize a special tool was used to fit the plug end assembly, but do recall that end looked odd in some way in which the plug was fitted over the cable. I was concerned the old loom might split or tear if I played with it too much, so decided to leave it alone and go the back door route.

Cheers,

David

[David Dunlop]

Not much work done on the project this past week beyond restocking soldering supplies and getting familiar with the new soldering station.

However, the attached item arrived in the Mail on Wednesday, compliments of Bruce Parker. It has tidied up quite well and the few missing bits should be easy enough to track down. It is now penciled into the project right after I finish getting the two receivers up and running.

The real gem about this Coil, Aerial Tuning unit is that inside, it is still the original, pristine factory No. 2 Brown paint. Not faded at all from exposure to light of any kind for 74 years. It will definitely be the item scanned in for matching when the time comes for painting.

I thought I would now also post another photo of the project overall to date. Had to transfer in another section of wireless bench from the workshop to accommodate everything, but I had planned for that some years back when designing the Wireless Table setup. Top shelf holds the Main Set Receiver and Coil, Aerial Tuning. The lower shelf the Remote Receiver and Case, Remote Supply Unit, Accessories and spare parts receiver. The starting point Aerial Bag and F-Rods is still on the wall. The tea towel on the Main Set Receiver is not original to the 52-Set. It's 'Cat Proofing', held down by a 2-inch binder full of 52-Set literature/reference manuals.

So, some progress is being made after all.

David

[David Dunlop]

Finally finished with the reconnection of the AC Line Cord to the chassis of the ZE-11 Remote Supply. In the attached photo you can see one lead just left of centre, curving past a hex nut and up to a terminal on a toggle switch, and just left of that, the second longer lead arcing up towards the camera and then on down to a terminal on the AC Selector Socket.

Having done that, I plugged in the supply and turned the electrons free. Low tension came in on target at +12V AC, but the high tension output was only +15V DC instead of the anticipated +150V DC. The input voltages to the OZ4 checked out at +201 V AC, so the transformer is OK, Downstream of the OZ4 checked out with the correct amount of resistance, so back to retest the OZ4. Bummer! It came in at barely 8% effective. Can’t really complain. It is probably the original 1943 Marconi OZ4.

Now to track down a good OZ4 and try again.


David

[David Dunlop]

Well, a minty new OZ4 has now been installed in the supply, and even a diode based replacement constructed...just in case. Both work beautifully in another piece of equipment. Not so much in this supply. Sigh.

I should qualify that. They are working just fine but something downstream in the circuit has now reared its head to say hello with a grin! The current suspect is the C25A/B capacitor can that covers both sides of the filter choke. Seems more disassembly and testing is ahead.

This is almost as exciting as taking a CMP apart with a 1/4-inch socket set!

David

[Chris Suslowicz]

You'll almost certainly find that C25 is no longer a capacitor and needs re-forming or replacing. Old electrolytic caps lose the insulating layer on the plates/foil over time if not used, and act as resistors instead. If power is applied they can explode due to a build up of pressure caused by electrolysis.

There are ways round this, using a variable voltage supply to bring it back to life slowly, or a "proper" re-forming unit that applies pulsed DC in an attempt to re-form the aluminium oxide insulating layer.

Chris.

[David Dunlop]

With the assistance of Jacques Fortin, I was able to find an original replacement C25A/B capacitor for the Remote Supply. It should arrive next week and it will be great to get that portion of the project back on track.

In the meantime, I have been reading through the 2” binder of 52-Set manuals I have accumulated, and realizing I should have purchased a 3” binder, as more documentation keeps popping up.

In the process, a mystery has surfaced in the Master Parts Identification List for the 52-Set, that I want to put out to everyone for review. I will preface that comment by stating whoever did the proofreading for this document back in 1944-1945 did a great job. Quite a few corrections are noted in the descriptions. As an example, the canvas cover that rolls down over the front of the Carrier Assembly should be correctly identified on the front of it as a ‘COVER’, but some early production of the item marked it as a ‘CURTAIN’ and that term is to be disregarded.

Now to the mystery. My understanding of the 52-Set production run from CMC, is that the early sets were finished in the same wrinkle olive green as the preceding Wireless Set No. 9 Mk I Cdn. This was then switched to No. 2 Brown wrinkle finish, which covered the bulk of the production run. Finally, there is the possibility that the colour switched back to wrinkle olive green close to the end of the production run.

Where it gets interesting in the Illustrated Parts List is that the colour ‘Khaki’ is mentioned for the finish on the three spare parts and tool boxes and once for the case used on the Remote Receiver. In another location the Remote Receiver Case is referenced as being ‘Brown’ . The Main Set Carrier is always referenced as ‘Brown’.
The canvas carrier cover previously mentioned is always referred to as ‘Brown’.

The Serial Numbers of the parts I have found run from the high 7,000 range to the high 8,000 range. The interior of the ATU I received from Bruce Parker is finished in No. 2 Brown, and it has the SN 8963, so I am confident that if all relevant parts are eventually finished in wrinkle, or flat, No. 2 Brown, I will be OK. And a brown canvas for the cover should be easy enough to track down. But the reference to ‘Khaki’ puzzles me. I do not recall ever seeing it as a reference colour before on anything vehicle or signals equipment related, other than canvas goods. No. 2 Brown is so distinctly brown it seems hard to think it would be called anything else, so I am thinking ‘Khaki’ must be an error.


David

[Bruce Parker (RIP)]

I'm not sure khaki is inconsistent. Radio colours matched truck colours to a degree, the big differences being that early radio equipment had a dark green that wasn't matched on vehicles, and I'm pretty certain no radio gear was ever painted 'light stone' from the factory. A good deal of mid war radio ancillary parts (spares and parts boxes, splitters, signal lamp battery boxes come to mind) were khaki, as were trucks prior to 1943.

Originally Posted by David Dunlop

With the assistance of Jacques Fortin, I was able to find an original replacement C25A/B capacitor for the Remote Supply. It should arrive next week and it will be great to get that portion of the project back on track.

In the meantime, I have been reading through the 2” binder of 52-Set manuals I have accumulated, and realizing I should have purchased a 3” binder, as more documentation keeps popping up.

In the process, a mystery has surfaced in the Master Parts Identification List for the 52-Set, that I want to put out to everyone for review. I will preface that comment by stating whoever did the proofreading for this document back in 1944-1945 did a great job. Quite a few corrections are noted in the descriptions. As an example, the canvas cover that rolls down over the front of the Carrier Assembly should be correctly identified on the front of it as a ‘COVER’, but some early production of the item marked it as a ‘CURTAIN’ and that term is to be disregarded.

Now to the mystery. My understanding of the 52-Set production run from CMC, is that the early sets were finished in the same wrinkle olive green as the preceding Wireless Set No. 9 Mk I Cdn. This was then switched to No. 2 Brown wrinkle finish, which covered the bulk of the production run. Finally, there is the possibility that the colour switched back to wrinkle olive green close to the end of the production run.

Where it gets interesting in the Illustrated Parts List is that the colour ‘Khaki’ is mentioned for the finish on the three spare parts and tool boxes and once for the case used on the Remote Receiver. In another location the Remote Receiver Case is referenced as being ‘Brown’ . The Main Set Carrier is always referenced as ‘Brown’.
The canvas carrier cover previously mentioned is always referred to as ‘Brown’.

The Serial Numbers of the parts I have found run from the high 7,000 range to the high 8,000 range. The interior of the ATU I received from Bruce Parker is finished in No. 2 Brown, and it has the SN 8963, so I am confident that if all relevant parts are eventually finished in wrinkle, or flat, No. 2 Brown, I will be OK. And a brown canvas for the cover should be easy enough to track down. But the reference to ‘Khaki’ puzzles me. I do not recall ever seeing it as a reference colour before on anything vehicle or signals equipment related, other than canvas goods. No. 2 Brown is so distinctly brown it seems hard to think it would be called anything else, so I am thinking ‘Khaki’ must be an error.


David

[David Dunlop]

This little gem arrived earlier in the week from Jacques Fortin and I would like to thank him on two counts. First, for the presence of mind a number of years ago to carefully disassemble a surplus remote supply unit and save the parts, rather than simply tossing the entire item. And secondly, for taking the time to search his parts to locate it and make it available to me.

Factory rated for 20uF on both sides when new, it currently checks out at 21uF and 27uF. I can now desolder the suspect capacitor in my ZE-11 Remote Supply and test it against this one to see which one is healthier. I was reluctant to pull the existing cap until I knew I had a suitable replacement, so that all potential work could be done in one sitting. A necessary consideration when dealing with an electronics work bench that is not cat proof.

David

[David Dunlop]

Well, long story short, I was able to successfully reform the wonky capacitor pair on the weekend and everything in the circuit downstream of the OZ4 rectifier is now in good working order.

That being said, however, a new problem has now been revealed. The input voltage to the OZ4 is not balanced for some reason. 50V too low on one side. More investigations ahead I fear. Sigh!

David

[Chris Suslowicz]

Originally Posted by David Dunlop

Well, long story short, I was able to successfully reform the wonky capacitor pair on the weekend and everything in the circuit downstream of the OZ4 rectifier is now in good working order.

That being said, however, a new problem has now been revealed. The input voltage to the OZ4 is not balanced for some reason. 50V too low on one side. More investigations ahead I fear. Sigh!

David

Is the correct vibrator fitted? If it's a series type (as used in the WS19 Supply Unit No.2) then the coil will drop some of the voltage to one half of the transformer primary - and the centre-tap is not in the centre on that supply unit to account for this. You probably need to fit a shunt vibrator (he said, without looking at the circuit diagram).

Chris.