Wireless Set No. 52 Canadian - Project

[David Dunlop]

I’ve been looking at the Master Parts List for the 52-Set, with regards to the five large rectangular electrical Plug and Socket assemblies. All are listed as replacement items, as complete assemblies. In spite of the fact they can be disassembled for repair, the only individual part that is separately listed is the Leaf Type Connector contacts for the socket assemblies. The Blade Type Connectors for the plug assemblies, is oddly not listed separately.

Now I wonder if these Plug and Socket assemblies are covered in more detail in the Parts Lists for other wireless equipment manufactured by Canadian Marconi?

David

[David Dunlop]

Further to the quest for information on the large rectangular bakelite 8-Pin Connector Plugs and Sockets on the 52-Set (as per Posts 28 and 35), can anyone with an original British made Wireless Set No. 9 confirm if these same connectors were used in the manufacture of the British No. 9 Sets? This may help trace the origin of these connectors.

David

[Bruce MacMillan]

I don't have access to a Canadian WS9 anymore but the schematic shows a similar style of connector as the WS52.

CMC only built the receiver for the WS9, the xmtr being built by Northern Electric. That would suggest that there was a third party manufacturer or somebody shared the product. Both companies had the capability to produce them.

[David Dunlop]

That’s interesting news, Bruce. I was not aware of that production sharing for the Canadian Wireless Set No. 9.

There is an illustrated parts list on the British Royal Signals site for the Canadian No.9 Set I have requested a copy of, so will see what it shows for looks and nomenclature, compared to the 52-Set Cdn for these connectors. Then, with some luck we might be able to push the references back to what STC in England was doing.

David

[Chris Suslowicz]

Originally Posted by Bruce MacMillan

I don't have access to a Canadian WS9 anymore but the schematic shows a similar style of connector as the WS52.

CMC only built the receiver for the WS9, the xmtr being built by Northern Electric. That would suggest that there was a third party manufacturer or somebody shared the product. Both companies had the capability to produce them.

Given that the remote receiver was usable as a spare for the set receiver, and that the WS52 and WS9 remote receiver power cables are virtually interchangeable, I'd say the connectors are identical in construction, if possibly different in pin configuration. Whether they're an exact copy of the ones used in the STC-built WS9 is another matter, but I would not be surprised to find that they were.

Chris.

[Tim Bell]

Chris

You are welcome to inspect my Canadian Ws9 anytime.

Cheers

Tim

[David Dunlop]

Finally got back to some thinking about the potential short in my Main Set Receiver Connector Socket this past week. In particular, the fact that I had noticed when connecting the Remote Supply Connector Plug to the socket, the retaining screw did not seem to run home as far as it did when I connected this cable to my backup receiver. That in turn got me wondering it this screw might be jamming on some loose bits inside and perhaps be part of the short problem.

Add to that, I was curious if it might be possible to isolate if the short was in the 12 Volt LT circuit, or the 150 Volt HT circuit. So I dug out my trusty old 2 Amp 12 Volt DC Trickle Battery Charger to jumper onto the 12 Volt circuit and see what happens.

I first tested the charger output. It was producing 11.78 Volts DC, along with 6.69 Volts of AC. I first jumpered it to the +12Volt terminal on the backup receiver socket and negative to chassis ground. The panel indicator lamp on the backup receiver lit straight away and I got a reading on the meter of 8 Volts DC LT. Turned on the calibrater and its indicator lamp lit and the meter reading dropped to 7 Volts and held. I waited a minute, switched off the calibrator and the meter went back up to 8 Volts and held.

I then switched the charger over to the Remote Receiver and jumpered it up in the same manner. The results were virtually identical to the backup receiver.

I am pleased with those results. Next, I am basically going to repeat this test with the Remote Supply, using jumper cables for both the 12 Volt LT and 150 Volt HT circuits. Basically bypassing the physical connection of the Remote Supply Connector Cable to the receivers. Hopefully that will provide some further useful information.

And while I was mucking about with the Connector Socket on the back of the backup receiver, I noticed the long paper label that runs across the middle of it with the Terminal IDs printed on it was missing. A closer look in that area revealed a cast oval mark with 'CMC' in the middle of it, about one third of the way in from one end. Photo attached. Pleased to finally find one of these marks and hope to find more as the project progresses.

David

[David Dunlop]

I did the jumpered test of the Remote Supply to the Remote Receiver late yesterday and the receiver lit up beautifully. After about a 10 minute warmup, I took meter readings for the valves. All registered and 'look' to be in the right range of values, but to be sure, I sent a copy of the recorded values to a friend in Arizona who operates a 52-Set Cdn on the air on a regular basis to see how my readings compare to his receiver.

The audio seemed a bit higher in white noise than it should and part of that may be some oxide build up on the various control contacts from lack of use over the years. The audio from the crystal calibrator was a bit weak but the 1000, 100 and 10 Kc pips could all be heard.

The only fly in the ointment was a nil reading for HT on the meter. Likely suspect is the R58A resistor (or resistor pair as it turns out) may have gone South. Now if I can only figure out where the heck they hid the little sucker(s) on the chassis, I can test them and see how close I get to the rated 600,000 Ohm value.

At least I have narrowed the short down to being intermittent and internal to the connector socket. It's nice to make progress on issues.

David