Wireless Set No. 52 Canadian - Project

[David Dunlop]

With the LOCKS, Panel and SWITCHES, Toggle assemblies both safely out of the way now, I can count 25 (including one broken one and one missing one) likely candidates for being panel screws holding the Sender front panel to the main chassis frame and/or sub chassis panels.

I have a piece of HD foam insulation available which is a little smaller in size than the front panel plate and I will be using that to fasten the panel screw into as I remove them. I have never been one to dump all the screws from something in a big pile and randomly stuff them back in wherever when I have finished working on something. It may take a little longer to organize this approach, but nobody is paying me by the hour to do the work and I know if a screw is going back into a hole it came out of easily, it should go back in just as easily.


David

[David Dunlop]

This Sender seems to give up its mysteries just as readily as revealing new ones to sort out. After careful removal of the 25 panel screws I had previously identified, the front panel was still firmly secured across the mid-section of the chassis. It was then that I realized the upper corners of the Flick Drive Assembly Boxes are also secured to the front panel. By the same screws that serve as the setscrews for the PLATES, Stop, No. 1. In realizing that, it suddenly made sense why the sixth such PLATES, although not installed at the far right side of the panel, still needed the lone setscrew fitted. That mystery now solved, but I still need to sort out why the PA TUNE only required the one, left hand PLATES.

Once those six screws were removed and secured, the Sender front panel lifted clear of the chassis. As usual, several panel screws are missing lock washers and one for certain is oversize. Several are also longer than they need to be. I suspect if any were damaged at some point, the easiest replacement was used rather than getting the proper length. Note to self to find appropriate replacement screws for reassembly.

The two INDICATORS are top heavy when freed from the front panel and swing on the gearbox as a result. I think it should be fairly easy to get the left one set to ‘0000’ prior to putting everything back together.

The really good news was with the middle Flick Drive Assembly. The retaining spring for the two Flick Arms had indeed disconnected from the Lower Arm and as a result, the Lower Arm had fallen away from the Flick Control Shaft. You can see the Lower Arm lying above the shaft in the second photo.

The paint on the right hand Flick Drive Indicator Flags is factory original and in very good shape. When exposed to light for a while and then put into darkness, the upper white sections of the two flags glows bright green. The white on the other two sets of flags has been painted over at some point with a plain flat white paint that did not adhere well to the underlying luminous paint. It has all blistered and lifted. In the dark, only the outer edges still show a slight glow and you can see where the newer paint was applied in large gobs with a brush. I now have a supply of the correct luminous paint so these two sets of flags will get a repaint.

Pretty good access overall for getting at internal chassis components fro a good cleaning now.

Have to take a closer look at the broken panel screw on the right side upper chassis rail now as well, to see how best to remove it.

David

[David Dunlop]

I have been taking a closer look at the panel mounting hardware on this Sender. A two-part reason for this.

Firstly, I want to know exactly what it is I have on this Sender, and secondly, once knowing that, I want to try and determine what is correct and what is not.

I started by numbering all 31 screws I had removed, on the foam board I transferred them to, and then I spec’d each of them out and recorded the data obtained. Apart from seven specialty screws, all others were 6 – 32 thread cutting of ¼, 5/16. 3/8 or ½ inch lengths.

I made some inquiries about possible specific names for thread cutting screws, in the process of which I stumbled across references to SEMS Fasteners. When I looked these fasteners up on line, it turns out pretty much any screw or bolt can become a SEMS Fastener. This fasteners claim to fame is the fact the shank of the screw, directly under the screw, or bolt, head is machined down slightly thinner than the following thread. A split washer is then fitted in that space and essentially held captive there.

With the exception of the previously mentioned specialty screws and two other in the panel, this type of fastener was what was being used as the panel mounting hardware. When I went into the Hardware Listing for the 52-Set, I found them listed as SEMS Fasteners. The big advantage of this hardware on an assembly line is the amount of time saved at stations where the workers do not have to fit individual screws and washers together before installing them. Both pieces are automatically together.

The other interesting thing in the Hardware Listing was that only two lengths of 6 – 32 SEMS Fasteners were used installing the front panels: 5/16 and 3/8 inch. So the ¼ and ½ inch ones I have present are clearly substitutes. That is a big help at this point.

David

[David Dunlop]

At some point the front panel of the Sender took a hit on this TERMINALS, snapping the small phenolic resin mounting plate for it. I had hoped it was a simple break that could be carefully glued back together, but no such luck. As you can see, a clean break on the left side but nearly 1/8-inch of material has gone missing on the right side.

Fortunately, an identical TERMINALS is mounted on a somewhat larger phenolic board on the 52-Set Receiver and I have one available on my spare receiver. I will have to identify and source the small plated brass tube rivets used to mount the board to the front panel before I can do the replacement, but at least it is doable.

David

[David Dunlop]

It looks like the only electrical component that was replaced during the 1966 202 Workshop overhaul was this capacitor. The orange coloured one on the upper right side of the photo. It functions in the PA Bias Circuit as the AF Bypass and is rated at 5 mf and 300 Volts. The original was nearly 1 inch in diameter. This one would be about two thirds of that size.

Not bad really for a set that was likely in service over 20 years at the time of overhaul.

David

[David Dunlop]

I was able to get the usual assortment of nylon, plastic and fine brass toothbrushes out today, along with a small electronics vacuum and an air gun set to 30 lbs., and get most of the dust and dirt cleaned from the chassis interior, followed by a careful wash and dry where needed.

Included in that process was the IPA 7 – 16 MC Flick Drive assembly from which the lower flick arm had become disconnected. The parts were in good shape and cleaned up well. The reassembly was straightforward and it is nice to see the parts back together again. I will refurbish the upper Indicator Flags on the three drives at a later date and try and get all that painting done and out of the way at once.

One thing to be aware of with this particular Flick Drive. It is not as secure in the chassis as the other two when freed from the front panel and has a tendency to wobble a bit if bumped.

David

[David Dunlop]

The two bottom sidepieces of the Sender chassis form the two rails it slides in and out of the Carriers No. 4 on, and they are held in place at the front of the chassis by the two lowermost panel screws. A pair of countersunk screws secures the back ends of these two rails.

Standing water a couple of inches in from the front of the rails had created a pair of noticeable rust blisters on these rails and I found these dug into the paint on the inner base of the Carriers enough to really make it hard to manoeuvre the Sender in and out of the Carriers as the rust blisters really dug into the paint.

The paint will eventually get stripped out of the interior of the Carriers, but in the meantime, I took advantage of the access to the bottom of the rails to buff the rust away and get a smooth metal surface back where it belonged.

One thing of note with these rails, as per the photos attached. They are heavy for their size and when the front set of retaining screws are removed, the rails have a tendency to swing towards each other. The one on the left about ¼-inch and the one on the right about 1/8-inch. Since these rails hold the thread for the panel screws, they need to be pulled into alignment when the panel goes back on. A small set of spring clamps should work nicely.

David