Wireless Set No. 52 Canadian - Project

[Chris Suslowicz]

Originally Posted by David Dunlop

I have no idea what the correct nomenclature ID is for these parts, but they are the terminal tag strips from inside the 8-pin connector assemblies used to connect the three main set components to one another in the Carriers No. 4.

These parts, along with the rectangular blade contacts from the plug assemblies are not listed in the Master Parts List. The complete, various 8-pin plug and socket assemblies are covered, as are the leaf type socket connectors. Perhaps these terminal tag strips and the blade connectors were considered robust enough to never need replacing. By comparison, you can see a lot of stretched and broken leaf connectors from having had screwdrivers jammed into them in an attempt to turn their retaining screws, which is a totally incorrect way of trying to work on these connectors.

The parts must show up in another manual reference somewhere.

David

Probably not: they're a Canadian Marconi item and probably only available as a complete unit, configured to the actual application. (Especially given the difficulty of changing an individual contact without wrecking the spring.)



Chris.

[David Dunlop]

Hi Chris.

I had forgotten about the ‘in house’ factor of these connectors at Canadian Marconi. They were also using them with some wartime navy wireless equipment and the WS No. 9 Mk I Cdn.

I am going to have to make an effort to get a copy of the Master Parts List for the Wireless No. 9 Mk I Cdn to better understand how much of the bits from it carried over into the 52-Set.

David

[David Dunlop]

This smaller Tag Panel supports a pair of capacitors and a single resister and can be seen in the photograph in Post #598, in the upper left quadrant, its mounting bracket secured under the small cleat retaining the tubular, plated copper lead shield.

Other than a pair of single capacitors held in place by cleats in a couple of places on the chassis, this Tag Panel is probably the easiest to remove so far.


David

[David Dunlop]

This particular Tag Panel has been the most challenging to remove so far. It is mounted to the right side of the top rear section of the receiver chassis, on two small metal posts, riveted in place. The two left end capacitors on this Tag Panel are just visible in the upper left corner of the 4th photograph in Post #579.

This Tag Panel is an excellent example of the type of pre-wiring that went into these sub-components, prior to their installation on the receiver chassis on the main production line at Canadian Marconi.

You will notice on the backside of this Tag Panel, several interconnecting leads have been soldered into place, in addition to the mounting of the five capacitors and four resisters.

The brown, phenolic bar, riveted in place at either end on the rear of the Tag Panel, allows the panel to stand away from the receiver chassis plate enough to prevent the interconnecting leads and tag assemblies from making any contact at all with the metal chassis.

Probably not the most entertaining of things to read about regarding the 52-Set, but with the surviving supply of original documentation on the 52-Set what it is, I feel the more information that can be made available, for anyone else, the better, and sooner or later, it is bound to tie in with some other information somewhere else.

David

[Mike K]

Is that two layered insulation on the wires ? On a couple of the wires, I think I can can see a black covering, then a cotton layer over that black stuff. On other wires it is a plain PVC ? Quite a mix of insulation .

[David Dunlop]

Afternoon, Mike.

From the ends, up close, it is just a form of 1940’s ‘plastic’ sleeve. The jumpers are solid tinned copper leads and I think these black sleeves were just an added insurance against the leads shorting against the chassis behind the panel, as a possible result of any misadventure the receiver might be involved in.

They are slightly loose on the leads but for the most part do not move easily due to these leads having been drawn in rather close to the back of the panel when soldered in place.

So basically just the solid lead and the sleeve, Mike.

Best regards,

David

[Chris Suslowicz]

The trade name was "Systoflex" and was a varnished woven cotton tube. I think yellow was the most common, but other colours were produced.

There was also varnished cambric tape, "Empire Tape" and Empire Cloth used in cable insulation and transformer/coil manufacture.

Chris. (Yes, I'm a mine of useless information.)

[Chris Suslowicz]

Originally Posted by David Dunlop

Afternoon, Mike.

From the ends, up close, it is just a form of 1940’s ‘plastic’ sleeve. The jumpers are solid tinned copper leads and I think these black sleeves were just an added insurance against the leads shorting against the chassis behind the panel, as a possible result of any misadventure the receiver might be involved in.

They are slightly loose on the leads but for the most part do not move easily due to these leads having been drawn in rather close to the back of the panel when soldered in place.

So basically just the solid lead and the sleeve, Mike.

Best regards,

David

It's also a lot more efficient for the assembly line workers: no tedious stripping of insulation (with the risk of nicking the conductor and creating a weak spot). Just a spool of tinned copper wire, a pair of sidecutters, and a tray of pre-cut sleeving (or a reel and pair of scissors, but pre-cut is faster).

Feed the wire through the first tag, slip the sleeving on, feed the end through the second tag, wind the end round the second tag, (snip end if necessary), pull wire taut and wind around first tag, then cut it and move on to the next pair of tags, Soldering would be the last step, possibly by a different operator.

Because it's all rigidly fixed (and I'm sure we've all cursed the construction method employed when trying to remove components fitted like this), it can be inspected before soldering and any mis-wiring rectified, then tested after soldering.

Wiring looms would be built on a board with nails/pegs or clips to hold the end of each lead, marked for wiring colour, and laced on the board ready for installation.

(I don't know if you've ever considered the WS19 control boxes, but they must have been built in the open, probably in a jig to hold the switches and connectors in the correct position, before being folded into the right shape and fitted to the outer shell of the box.)

Best regards,
Chris.