Wireless Set No. 52 Canadian - Project

[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

[David Dunlop]

I just noticed this variation this afternoon.

The first photo attached was taken from the 52-Set Manual, so it was very likely taken sometime in 1943 from an early (pre) production Carriers No. 4. Notice the bottom of the mounting rails at the side of the Carriers for the Coils, Aerial Tuning to be fitted The end is cut back at an angle upwards where it sits just in front of the hole for the Mounting Clamp to be installed. Improved access perhaps?

The second photo is the same rails on my Carriers No. 4. It has straight cut 90-degree ends.

Does this mean there might be early and late production versions of these mounting rails for the Coils, Aerial Tuning?

Another possibility is the angled cut never made it into production. Same reason applying in either case: Production Line efficiency and streamlining removed a step deemed unnecessary.

David

[David Dunlop]

It has been a while since I last worked this little sub-project, but I need to get back to it now since I will be needing a completed replica of this particular Connector soon enough. It helps the Receiver and Sender communicate with one another and it will have to be ready to go when I get the Main Set Receiver fully up and running.

By means of a recap, I last worked this sub-topic back on Page 16, Post #476 of this thread.

Note to Self: It would be a good idea to keep a ‘topic log’ handy so even I can readily find information I might need to refer back to at a later date.

When I left off this work, the central pin assemblies just filled the brass sleeves, so there was no room at all to insert any HT Cable. First new step was to trim the black insulation back to just ¼-inch in length and trim it square. This will now allow one half inch of cable to fit into the sleeve

The next step will be to trim one end of the HT Cable I nave to expose enough of the central, braided copper core wire to pass completely out the end of the central pin when the cable is fully seated in the sleeve. This should work out to be about 1-1/2 inches. I will also need to pick up a small assortment of yellow heat shrink tubing and replenish my stocks of black heat shrink. The plan is for this first end of the Connector to be the insulated end located at the Receiver, and this end also bears the yellow ID Sleeve for the Connector.

David

[David Dunlop]

I was able to move forward on both the Reno and this sub-project today.

The sub-project was broken down into three steps, the first step was the one completed today, and for a variety of reasons it was the most important as it put a number of assembly theories for this LEADS to the test. All have passed so far.

The first thing was to measure off 1-1/2 inches back from one end of my piece of 7mm rubber sheathed, braided copper core HT Cable, and tape that point off. This is the start of the process to get that measured length of the central copper core exposed to pass through the tip assembly of the LEADS.

Once measured off, I used a thin. Blade cutter to slice through the outer rubber sheath of the cable at the edge of the tape. I then made a longitudinal cut from the circumference cut at the tape to the end of the cable and peeled off the rubber sheath to expose the inner insulation.

I was lucky the inner insulation was a soft clear plastic product that when cut into carefully, the insulation could be carefully bent at the cut and it would slowly split by itself to the inner copper core. I removed the insulation in two sections as shown to make it easier to slide the insulation off the copper core. As I removed the second section of insulation, I slowly twisted the insulation in the direction of the stranding on the copper core to tighten up the core wires as much as possible. I wanted to do this so it would all easily clear the pin assembly as it passed through it.

The next step was to insert this end of the cable all the way into the pin terminal I had fabricated.

David