Wireless Set No. 52 Canadian - Project

[David Dunlop]

By far the easiest items to remove so far in this project.

With the BLOWERS off the Door Assembly, I was able to get a fingertip up under the top lip of the panel and jamb the hex nuts up against the back of the front panel. It felt like both hex nuts were only on the Screw-Eye shanks about one nut thickness up. A careful counter clockwise turn of the Screw-Eye and each unfastened smoothly.

These two bits had to come out because they pass through both the front panel and the front upper angle of the chassis frame assembly. Now both tagged and bagged.

David

[David Dunlop]

I was initially thinking I would be able to simply unscrew the antenna feed line from the centre rear terminal of this SOCKETS Assembly and it would lift off with the front panel assembly. Closer inspection eventually proved ’no such luck’.

Of the three machine screws securing the Sockets Assembly to the front panel of the Sender, only the lower left one is mounted directly to the front panel. My recent inspection mirror purchase proved useful once again, as when I took a closer look at the other two sets of hardware behind the front panel, I realized both those corners of the chassis frame had also been reinforced with steel gussets similar to the ones evident in the second photo. Fortunately, there is enough clearance behind the front panel to reach all three hex nuts with my ¼ drive socket set.

The challenge is going to be releasing, and removing the 3/8-inch hex nut on the centre terminal on the back of the SOCKETS Assembly. There is no play whatsoever in the heavy duty solid wire feed to the terminal connector held in place by that hex nut and the terminal connector itself is angled downward, reducing the swing one can get with a small wrench. It’s shaping up to be one of those fifth of a turn, flip the wrench, fifth of a turn kind of tasks.

David

[David Dunlop]

It was a bit of a slow process last night to get the SOCKETS, Antenna assembly off the front panel, but I am sure glad the Sender is resting safely on its back for this work. Gravity definitely works in ones favour when removing hardware. Especially when so much of it turns out to be plated brass and you have no hope of securing, or retrieving it, with a magnet. I have only had one part get away on me and it simply fell down to the back of the chassis onto the work desk.

As expected with this SOCKETS, I had to start on the centre rear terminal post with a small 3’8 inch spanner from the right hand side and work the retaining hex nut loose a couple of turns. The locking ring terminal on the end of the antenna feed wire fits between two small flat washers and then the hex nut was applied to tighten everything down.

Once the hex nut was loose, I switched to my ¼ drive 3/8-inch socket with no handle. There is simply no room to use one. I was able to place it over the hex nut and hold it there with one fingertip of my left hand, coming in from the top of the chassis. I could then reach in from the right side of the chassis with thumb and index finger of my right hand to slowly turn the socket. When the hex nut came free of the centre post, it simply dropped inside the socket and the flat washer rested on the outer lip. I could then place the socket down on the phenolic board behind the SOCKETS, Antenna and slide it to the right side of the chassis for removal. A pair of small needle nose pliers was then used to gently move the antenna feed wire and terminal off the post and the inner flat washer just dropped onto the phenolic board where I could retrieve it with a fingertip.

The three sets of hardware that actually mount the SOCKETS, Antenna to the front panel of the Sender are held in place with 5/16-inch hex nuts. There is enough space behind the front panel to access them with the appropriate socket on a quarter drive handle, but not much room to swing the handle. The solution was to hold the socket in place and use a screwdriver to undo the machine screws from the front of the SOCKETS. As soon as the screws loosened, I found I could easily unscrew them and pull them out. The hex nuts and small lock washers simply fell back into the 5/16-inch socket. Interestingly enough, only the mounting hardware in the lower left section of the SOCKETS still had their original lock washers (external star style). The other two must have disappeared when the Sender was overhauled.

Down to just a handful of things to release from the front panel now and then it should be just a pile of screws to undo to release the front panel from the chassis assembly.

David

[David Dunlop]

Here is how the Sender front panel looks now.

David

[David Dunlop]

A few more things are now out of the way today.

First off, I removed the mounting screws for the two PA TUNING COUNTERS. It was again interesting to notice, with this type of work, the number of screws one finds that have clearly been serviced at some point and they are missing their lock washers.

In any event, when the last screw came out of both COUNTERS, they both rotated very so slightly in a counter clockwise direction. You can just see the lower left side screw holes are now slightly blocked by the mounting plate of the front of each COUNTERS. Nothing a round wooden toothpick cannot realign when the front panel is ready to go back on.

David

[David Dunlop]

The second bit of work was removing the three 1/2-inch hex nuts and internal lock washers from the three switch assemblies along the lower right portion of the panel. I found a box head spanner gave the best support on the hex nuts for this work.


David

[David Dunlop]

This last bit of activity was more of an in depth study than actual physical work. I shall attempt that work tomorrow morning when my head is clear.

I was suspicious some time ago that the Power Selector Switch for MED, LOW and HIGH Power that is mounted directly above the LOCKS, Panel, looked very much like the Selector Switch on the front of the Canadian Wireless Set No. 19 Mk III Supply Unit No. 2. I took a look through the Parts Manuals for both sets this evening and indeed it is: SWITCHES, Toggle, 4-pole, 3-position ZA/CAN 0178.

What struck me as odd when I got my first live look at the 52-Set Sender, was the fact the SWITCHES, Toggle was set so far back from the rear side of the front panel. Only about half of the toggle lever actually sticks out from the panel. Eventually all cylinders started firing and I realized two key things. First, space was needed behind the panel for the lock slide to move up and block the toggle lever from reaching its lowermost, HIGH, power position. Second, the front mounting plate on the SWITCHES, Toggle was designed for a flush fit behind a wireless panel. Point One does not allow this, nor does the fact the LOCKS, Panel occupies the position where the lower mounting screw for the SWITCHES, Toggle would go on the Sender front panel. The work around for this by the Canadian Marconi Company Engineers is rather interesting.

A set of three cylindrical spacers was employed, along with a small, rectangular adapter plate, thereby keeping the switch and the lock unmodified.

In the last photo you can see two long spacers closest to the camera at the bottom of the Sender. These allow the two mounting screws for the lock to pass down and through the adapter plate. Between these two spacers you can see the thin line of the bottom edge of the mounting plate for the switch, with the square lock nut spot welded to it. Normally, the lower mounting screw for the switch would come in from the front of the plate and into the square nut. In this case, the mounting screw comes in through the adapter plate at the back and then into the square nut.

In the background and to the right of the lower right spacer, you can see the smaller spacer that is used for the upper mounting hole of the switch assembly. The upper spacer is shorter than the lower two to keep a constant gap between the rear of the Sender front panel and the switch mounting plate. It will be an interesting exercise getting that shorter upper spacer back in place when it comes time for reassembly.


David